[0001] The present invention concerns novel oxazolidinone antibiotic derivatives, a pharmaceutical
antibacterial composition containing them and the use of these compounds in the manufacture
of a medicament for the treatment of infections (e.g. bacterial infections). These
compounds are useful antimicrobial agents effective against a variety of human and
veterinary pathogens including among others Gram positive and Gram negative aerobic
and anaerobic bacteria and mycobacteria.
[0002] The intensive use of antibiotics has exerted a selective evolutionary pressure on
micro-organisms to produce genetically based resistance mechanisms. Modem medicine
and socio-economic behaviour exacerbate the problem of resistance development by creating
slow growth situations for pathogenic microbes, e.g. in artificial joints, and by
supporting long-term host reservoirs, e.g. in immuno-compromised patients.
[0003] In hospital settings, an increasing number of strains of
Staphylococcus aureus, Streptococcus pneumoniae, Enterococcus spp., and
Pseudomonas aeruginosa, major sources of infections, are becoming multi-drug resistant and therefore difficult
if not impossible to treat:
- S. aureus is resistant to ß-lactams, quinolones and now even to vancomycin;
- S. pneumoniae is becoming resistant to penicillin or quinolone antibiotics and even to new macrolides;
- Enteroccocci are quinolone and vancomycin resistant and ß-lactam antibiotics are inefficacious
against these strains;
- Enterobacteriacea are cephalosporin and quinolone resistant;
- P. aeruginosa are ß-lactam and quinolone resistant.
[0004] Further new emerging organisms like
Acinetobacter spp. or
Clostridium difficile, which have been selected during therapy with the currently used antibiotics, are
becoming a real problem in hospital settings. In addition, microorganisms that are
causing persistent infections are increasingly being recognized as causative agents
or cofactors of severe chronic diseases like peptic ulcers or heart diseases.
[0005] Certain heterocyclic compounds as antibacterial agents are known from
WO 2007/138974. Compounds for the treatment of multi-drug resistant bacterial infections are disclosed
in
WO 2006/134378. Piperazine derivatives, containing a quinoline analog moiety, useful in methods
of treatment of bacterial infections, are disclosed in
WO 02/50040.
[0006] Various embodiments of the invention are presented hereafter:
- 1) The present invention relates to novel antibiotic compounds of Formula (I)

wherein
"-----" is a bond or is absent;
R1 represents (C1-C4)alkoxy or halogen;
R1b represents H or (C1-C3)alkyl;
U and V each independently represent CH or N;
W represents CH or N, or, in case "----" is absent, W represents CH2 or NH;
with the proviso that at least one of U, V and W represents CH or CH2;
A represents -CH2-CH(R2)-B-NH-* or -CH(R3)CH2-N(R4)-[CH2]m-*; wherein the asterisks indicate the bond which is linked via the CH2-group to the oxazolidinone moiety;
B represents CH2 or CO; and
R2 represents hydrogen, OH or NH2;
R3 and R4 both represent hydrogen, or R3 and R4 together form a methylene bridge;
m represents the integer 0, 1 or 2; and
G represents phenyl which is mono-substituted in position 3 or 4, or disubstituted
in positions 3 and 4, wherein each substituent is independently selected from the
group consisting of (C1-C4)alkyl (notably methyl and ethyl), (C1-C3)alkoxy and halogen (notably fluorine); or
G represents a group selected from the group consisting of the groups G1, G2, G3, G4, G5 and G6 drawn below:


wherein
M represents CH or N;
Q and Q' independently represent S or O;
● Z1 represents N, Z2 represents CH, and Z3 represents CH; or
● Z1 represents CH, Z2 represents N, and Z3 represents CH or N; or
● Z1 represents CH, Z2 represents CR5, and Z3 represents CH; or
● Z1 represents CH, Z2 represents CH, and Z3 represents N; and
R5 represents hydrogen or fluorine.
[0007] The invention also relates to salts, especially pharmaceutically acceptable salts,
of the compounds of Formula (I).
[0008] The following paragraphs provide definitions of the various chemical moieties for
the compounds according to the invention and are intended to apply uniformly throughout
the specification and claims, unless an otherwise expressly set out definition provides
a broader or narrower defmition.
[0009] In this patent application, a bond interrupted by a wavy line shows the point of
attachment of the radical drawn.
[0010] Further, an asterisk in a group -CH
2-CH(R
2)-B-NH-* or -CH(R
3)-CH2-N(R
4)[CH2]
m-* as used for the substituent A indicates the bond which is linked via the CH
2-group to the oxazolidinone moiety.
[0011] Further, for avoidance of any doubt, a group -CH(R
3)-CH
2-N(R
4)-[CH
2]
m-* wherein
R3 and
R4 together form a methylene bridge, as used for the substituent A, means a group

[0012] Further, for avoidance of any doubt, a group

wherein "-----" is a bond means a group

wherein W represents CH or N.
[0013] Likewise, a group

wherein "-----" is absent means a group

wherein
W represents CH
2 or NH.
[0014] The term "halogen" refers to fluorine, chlorine, bromine or iodine; especially to
fluorine, chlorine or bromine; preferably to fluorine or chlorine. In another embodiment,
the term halogen as used for the substituent R
1 preferably refers to bromine.
[0015] The term "alkyl", used alone or in combination, refers to a straight or branched
chain alkyl group containing one to four carbon atoms. Representative examples of
alkyl groups include methyl, ethyl,
n-propyl, iso-propyl, n-butyl, iso-butyl, sec-butyl and tert-butyl. Preferred are methyl,
ethyl n-propyl and iso-propyl. Most preferred are ethyl and methyl.
[0016] The term "alkoxy", used alone or in combination, refers to an alkyl-O- group wherein
the alkyl group is as defined before. The term "(C
x-C
y)alkoxy" (x and y each being an integer) refers to an alkoxy group as defined before
containing x to y carbon atoms. For example a (C
1-C
4)alkoxy group contains from one to four carbon atoms. Representative examples of alkoxy
groups include methoxy, ethoxy, n-propoxy, iso-propoxy, n-butoxy,
iso-butoxy, sec-butoxy and tert-butoxy. Preferred are ethoxy and methoxy. Most preferred
is methoxy. Preferred (C
1-C
3)alkoxy groups, as used for the substituent G representing substituted phenyl, are
straight chain (C
1-C
3)alkoxy groups such as methoxy, ethoxy and
n-propoxy, notably methoxy and ethoxy.
[0017] Preferred groups G representing
"a group selected from the group consisting of the groups
G1, G2, G3, G4, G5 and
G6 drawn below:

wherein
M represents CH or N;
Q and
Q' independently represent S or O;
- Z1 represents N, Z2 represents CH, and Z3 represents CH; or
- Z1 represents CH, Z2 represents N, and Z3 represents CH or N; or
- Z1 represents CH, Z2 represents CR5, and Z3 represents CH; or
- Z1 represents CH, Z2 represents CH, and Z3 represents N; and
R5 represents hydrogen or fluorine"
as used for Formula (I) are those groups G wherein
M represents CH or N;
Q and Q' independently represent S or O;
- Z1 represents CH or N, Z2 represents CH, and Z3 represents CH; or
- Z1 represents CH, Z2 represents N, and Z3 represents N; and
R5 represents hydrogen.
[0018] Examples of such groups G are 2,3-dihydro-benzo[1,4]dioxin-6-yl, benzo[1,3]dioxol-5-yl,
3-oxo-3,4-dihydro-2
H-benzo[1,4]oxazine-6-yl, 3-oxo-3,4-dihydro-2
H-benzo[1,4]thiazine-6-yl, 7-fluoro-3-oxo-3,4-dihydro-2
H-benzo[1,4]thiazin-6-yl, 3-oxo-3,4-dihydro-2
H-pyrido[3,2-
b][1,4]oxazine-6-yl, 2-oxo-1,2-dihydro-quinoline-7-yl, benzothiazole-5-yl, benzothiazole-6-yl,
benzooxazole-5-yl and benzooxazole-6-yl and in addition to the above listed groups
also 6,7-dihydro-[1,4]dioxino[2,3-
c]pyridazin-3-yl. In a sub-embodiment, examples are 2,3-dihydro-benzo[1,4]dioxin-6-yl,
benzo[1,3]dioxol-5-yl, 3-oxo-3,4-dihydro-2
H-benzo[1,4]oxazine-6-yl, 3-oxo-3,4-dihydro-2
H-benzo[1,4]thiazine-6-yl, 3-oxo-3,4-dihydro-2
H-pyrido[3,2-
b][1,4]oxazine-6-yl, 2-oxo-1,2-dihydro-quinoline-7-yl, benzothiazole-5-yl, benzothiazole-6-yl,
benzooxazole-5-yl and benzooxazole-6-yl, and in addition to the above listed groups
also 6,7-dihydro-[1,4]dioxino[2,3-c]pyridazin-3-yl. In another sub-embodiment, examples
are 2,3-dihydro-benzo[1,4]dioxin-6-yl, 3-oxo-3,4-dihydro-2
H-benzo[1,4]oxazin-6-yl, 3-oxo-3,4-dihydro-2
H-benzo[1,4]thiazin-6-yl, 7-fluoro-3-oxo-3,4-dihydro-2
H-benzo[1,4]thiazin-6-yl, and 3-oxo-3,4-dihydro-2
H-pyrido[3,2-
b][1,4]oxazin-6-yl. Preferred are 2,3-dihydro-benzo[1,4]dioxin-6-yl, 3-oxo-3,4-dihydro-2
H-benzo[1,4]oxazin-6-yl, 3-oxo-3,4-dihydro-2
H-benzo[1,4]thiazin-6-yl, and 7-fluoro-3-oxo-3,4-dihydro-2
H-benzo[1,4]thiazin-6-yl. In a sub-embodiment preferred are 2,3-dihydro-benzo[1,4]dioxin-6-yl,
3-oxo-3,4-dihydro-2
H-benzo[1,4]oxazine-6-yl and 3-oxo-3,4-dihydro-2
H-benzo[1,4]thiazine-6-yl.
[0019] Further embodiments of the invention are presented hereafter:
2) A further embodiment of the invention relates to compounds according to embodiment
1), wherein the stereocenter at position 5 of the oxazolidin-2-one ring is in (R)-configuration:

3) A further embodiment of the invention relates to compounds according to embodiment
1), wherein the stereocenter at position 5 of the oxazolidin-2-one ring is in (S)-configuration:

4) A further embodiment of the invention relates to compounds according to any one
of embodiments 1) to 3), wherein "-----" is absent and W represents CH2 or NH (especially CH2).
5) A further embodiment of the invention relates to compounds of Formula (I) according
to any one of embodiments 1) to 3) wherein "----" is a bond and U, V and W independently represent CH or N, with the proviso that at least one of U, V and *W represents CH.
6) A further embodiment of the invention relates to compounds according to any one
of embodiments 1) to 3) or 5), wherein U, V and W each represent CH, or U and V each represent CH and W represents N, or U and W each represent N and V represents CH.
7) A further embodiment of the invention relates to compounds according to any one
of embodiments 1) to 6), wherein U represents CH.
8) A further embodiment of the invention relates to compounds according to any one
of embodiments 1) to 6), wherein U represents N.
9) A further embodiment of the invention relates to compounds according to any one
of embodiments 1) to 8), wherein V represents CH.
10) A further embodiment of the invention relates to compounds according to any one
of embodiments 1) to 8), wherein V represents N.
11) A further embodiment of the invention relates to compounds according to any one
of embodiments 1) to 3) or 5) to 10), wherein W represents CH.
12) A further embodiment of the invention relates to compounds according to any one
of embodiments 1) to 3) or 5) to 10), wherein W represents N.
13) A further embodiment of the invention relates to compounds according to any one
of embodiments 1) to 12), wherein R1 represents (C1-C4)alkoxy (preferably methoxy).
14) A further embodiment of the invention relates to compounds according to any one
of embodiments 1) to 12), wherein R1 represents halogen (preferably bromine).
15) A further embodiment of the invention relates to compounds according to any one
of embodiments 1) to 14), wherein A represents -CH2-CH(R2)-B-NH-*.
16) A further embodiment of the invention relates to compounds according to any one
of embodiments 1) to 15), wherein R2 represents hydrogen or OH.
17) A further embodiment of the invention relates to compounds according to any one
of embodiments 1) to 15), wherein R2 represents OH or NH2.
18) A further embodiment of the invention relates to compounds according to any one
of embodiments 1) to 15), wherein R2 represents hydrogen.
19) A further embodiment of the invention relates to compounds according to any one
of embodiments 1) to 15), wherein R2 represents OH.
20) A further embodiment of the invention relates to compounds according to any one
of embodiments 1) to 19), wherein B represents CH2.
21) A further embodiment of the invention relates to compounds according to any one
of embodiments 1) to 19), wherein B represents CO.
22) A further embodiment of the invention relates to compounds according to any one
of embodiments 1) to 14), wherein A represents -CH(R3)-CH2-N(R4)-[CH2]m-* wherein R3 and R4 together form a methylene bridge and m represents the integer 0, 1 or 2 (notably
1 or 2, and in particular 1), i.e. wherein A is

23) A further embodiment of the invention relates to compounds according to any one
of embodiments 1) to 14), wherein A represents -CH(R3)-CH2-N(R4)-[CH2]m-* wherein R3 and R4 both represent hydrogen; and m represents the integer 0, 1 or 2 (notably 1 or 2 and
in particular 1).
24) A further embodiment of the invention relates to compounds according to any one
of embodiments 1) to 23), wherein G represents a group selected from the group consisting
of the groups G1, G2, G5 and G6 wherein:
M represents CH or N;
Q' represents S or O;
- Z1 represents N, Z2 represents CH, and Z3 represents CH; or
- Z1 represents CH, Z2 represents N, and Z3 represents CH or N; or
- Z1 represents CH, Z2 represents CR5, and Z3 represents CH; or
- Z1 represents CH, Z2 represents CH, and Z3 represents N; and
R5 represents hydrogen or fluorine.
25) A further embodiment of the invention relates to compounds according to embodiment
24), wherein
M represents CH or N;
Q' represents S or O;
- Z1 represents CH or N, Z2 represents CH, and Z3 represents CH; or
- Z1 represents CH, Z2 represents N, and Z3 represents N; and
R5 represents hydrogen.
26) A further embodiment of the invention relates to compounds according to any one
of embodiments 1) to 24), wherein G represents a group selected from the group consisting of the groups G1, G2, G5 and G6 wherein:
each of M and Z1 represents CH or N;
each of Z2 and Z3 represents CH;
Q' represents S or O; and
R5 represents hydrogen or fluorine.
27) A further embodiment of the invention relates to compounds according to any one
of embodiments 1) to 24), wherein G represents a group selected from the group consisting of the groups G1 and G5 wherein:
each of M and Z1 represents CH or N;
each of
Z2 and
Z3 represents CH;
Q' represents S or O; and
R5 represents hydrogen or fluorine.
28) A further embodiment of the invention relates to compounds according to any one
of embodiments 1) to 24), 26) or 27) wherein G represents a group G5 wherein M represents CH or N; Q' represents O or S; and R5 represents hydrogen or fluorine.
29) A further embodiment of the invention relates to compounds according to any one
of embodiments 1) to 27) wherein G represents a group G5 wherein Z1 represents CH or N and each of Z2 and Z3 represents CH.
30) A further embodiment of the invention relates to compounds according to any one
of embodiments 1) to 28), wherein R5 represents hydrogen.
31) A further embodiment of the invention relates to compounds according to any one
of embodiments 1) to 30), wherein, if present, M and Z1 both represent CH.
32) A further embodiment of the invention relates to compounds according to any one
of embodiments 1) to 30), wherein, if present, M and Z1 both represent N.
33) A further embodiment of the invention relates to compounds according to any one
of embodiments 1) to 28) or 30) to 32), wherein, if present, Q' represents S.
34) A further embodiment of the invention relates to compounds according to any one
of embodiments 1) to 28) or 30) to 32), wherein, if present, Q' represents O.
35) A further embodiment of the invention relates to compounds according to any one
of embodiments 1) to 23) or 30) to 34), wherein, if present, Q represents S.
36) A further embodiment of the invention relates to compounds according to any one
of embodiments 1) to 23) or 30) to 34), wherein, if present, Q represents O.
37) A further embodiment of the invention relates to compounds according to any one
of embodiments 1) to 24), wherein G represents a group selected from 2,3-dihydro-benzo[1,4]dioxin-6-yl, 3-oxo-3,4-dihydro-2H-benzo[1,4]oxazin-6-yl, 3-oxo-3,4-dihydro-2H-benzo[1,4]thiazin-6-yl, 7-fluoro-3-oxo-3,4-dihydro-2H-benzo[1,4]thiazin-6-yl, and 3-oxo-3,4-dihydro-2H-pyrido[3,2-b][1,4]oxazin-6-yl.
38) A further embodiment of the invention relates to compounds according to any one
of embodiments 1) to 24), wherein G represents a group selected from 2,3-dihydro-benzo[1,4]dioxin-6-yl, 3-oxo-3,4-dihydro-2H-benzo[1,4]oxazin-6-yl, 3-oxo-3,4-dihydro-2H-benzo[1,4]thiazin-6-yl, and 7-fluoro-3-oxo-3,4-dihydro-2H-benzo[1,4]thiazin-6-yl (notably from 2,3-dihydro-benzo[1,4]dioxin-6-yl, 3-oxo-3,4-dihydro-2H-benzo[1,4]oxazine-6-yl, and 3-oxo-3,4-dihydro-2H-benzo[1,4]thiazine-6-yl).
39) A further embodiment of the invention relates to compounds according to any one
of embodiments 1) to 23), wherein G represents phenyl which is mono-substituted in position 3 or 4, or disubstituted
in positions 3 and 4; wherein each substituent is independently selected from the
group consisting of (C1-C4)alkyl (notably methyl and ethyl), (C1-C3)alkoxy, and halogen (notably fluorine).
40) A further embodiment of the invention relates to compounds according to any one
of embodiments 1) to 23) or 39), wherein, in case G represents phenyl which is mono-substituted in position 3 or 4, or disubstituted
in positions 3 and 4; wherein each substituent is independently selected from the
group consisting of (C1-C4)alkyl (notably methyl and ethyl), (C1-C3)alkoxy, and halogen (notably fluorine), whereby a (C1-C3)alkoxy substituent, if present, is a straight chain (C1-C3)alkoxy group which is attached in position 4.
41) A particular embodiment of this invention relates to the compounds according to
one of embodiments 1) to 40) wherein R1b represents H.
42) Another particular embodiment of this invention relates to the compounds according
to one of embodiments 1) to 40) wherein R1b represents (C1-C3)alkyl (in particular methyl).
43) Preferred compounds of Formula (I) as defined in embodiment 1) are selected from
the group consisting of:
- 6-((R)-5-{[3-(7-methoxy-2-oxo-2H-quinolin-l-yl)-propylamino]-methyl}-2-oxo-oxazolidin-3-yl)-4H-benzo[1,4]thiazin-3-one;
- 6-((R)-5-{[3-(7-bromo-2-oxo-2H-quinolin-1-yl)-propylamino]-methyl}-2-oxo-oxazolidin-3-yl)-4H-benzo[1,4]thiazin-3-one;
- 1-(3-{[(R)3-(2,3-dihydro-benzo[1,4]dioxin-6-yl)-2-oxo-oxazolidin-5-ylmethyl]-amino}-propyl)-7-methoxy-1H-quinolin-2-one;
- 7-bromo-1-(3-{[(R)-3-(2,3-dihydro-benzo[1,4]dioxin-6-yl)-2-oxo-oxazolidin-5-ylmethyl]-amino}-propyl)-1H-quinolin-2-one;
- 6-(5-{2-[3-(7-methoxy-2-oxo-2H-quinolin-1-yl)-azetidin-1-yl]-ethyl}-2-oxo-oxazolidin-3-yl)-4H-benzo[1,4]thiazin-3-one;
- 3-(7-methoxy-2-oxo-2H-quinoxalin-1-yl)-N-[(R)-2-oxo-3-(3-oxo-3,4-dihydro-2H-benzo[1,4]thiazin-6-yl)-oxazolidin-5-ylmethyl]-propionamide;
- N-[(R)-3-(2,3-dihydro-benzo[1,4]dioxin-6-yl)-2-oxo-oxazolidin-5-ylmethyl]-3-(7-methoxy-2-oxo-2H-quinolin-1-yl)-propionamide;
- 3-(7-bromo-2-oxo-2H-quinolin-1-yl)-N-[(R)-3-(2,3-dihydro-benzo[1,4]dioxin-6-yl)-2-oxo-oxazolidin-5-ylmethyl]-propionamide;
- 3-(7-bromo-2-oxo-2H-quinolin-1-yl)-N-[(R)-2-oxo-3-(3-oxo-3,4-dihydro-2H-benzo[1,4]thiazin-6-yl)-oxazolidin-5-ylmethyl]-propionamide;
- N-[(R)-3-(2,3-dihydro-benzo[1,4]dioxin-6-yl)-2-oxo-oxazolidin-5-ylmethyl]-3-(7-methoxy-2-oxo-2H-quinoxalin-l-yl)-propionamide;
- 3-(7-methoxy-2-oxo-2H-quinolin-1-yl)-N-[(R)-2-oxo-3-(3-oxo-3,4-dihydro-2H-benzo[1,4]thiazin-6-yl)oxazolidin-5-ylmethyl]-propionamide;
- (S)-2-amino-N-[(R)-3-(2,3-dihydro-benzo[1,4]dioxin-6-yl)-2-oxo-oxazolidin-5-ylmethyl]-3-(7-methoxy-2-oxo-2H-quinoxalin-1-yl)-propionamide;
- (R)-2-amino-N-[(R)-3-(2,3-dihydro-benzo[1,4]dioxin-6-yl)-2-oxo-oxazolidin-5-ylmethyl]-3-(7-methoxy-2-oxo-2H-quinoxalin-1-yl)-propionamide;
- 6-((R)-5-{[(R)-2-hydroxy-3-(7-methoxy-2-oxo-2H-quinolin-1-yl)-propylamino]-methyl}-2-oxo-oxazolidin-3-yl)-4H-benzo[1,4]oxazin-3-one;
- 6-((R)-5-{[(R)-2-hydroxy-3-(7-methoxy-2-oxo-2H-quinolin-1-yl)-propylamino]-methyl}-2-oxo-oxazolidin-3-yl)-4H-benzo[1,4]thiazin-3-one; and
- 6-((R)-5-{[(S)-2-hydroxy-3-(7-methoxy-2-oxo-2H-quinolin-1-yl)-propylamino]-methyl}-2-oxo-oxazolidin-3-yl)-4H-benzo[1,4]thiazin-3-one;
wherein the compound 6-(5-{2-[3-(7-methoxy-2-oxo-2
H-quinolin-1-yl)-azetidin-1-yl]-ethyl}-2-oxo-oxazolidin-3-yl)-4
H-benzo[1,4]thiazin-3-one may be (
R) or (
S) configurated.
44) In addition to the compounds listed in embodiment 43), further preferred compounds
of Formula (I) as defined in embodiment 1) are selected from the group consisting
of:
- 7-fluoro-6-((R)-5-{[(S)-2-hydroxy-3-(7-methoxy-2-oxo-2H-quinolin-1-yl)-propylamino]-methyl}-2-oxo-oxazolidin-3-yl)-4H-benzo[1,4]thiazin-3-one;
- 6-methoxy-4-(3-{[(R)-2-oxo-3-(3-oxo-3,4-dihydro-2H-benzo[1,4]thiazin-6-yl)-oxazolidin-5-ylmethyl]-amino}-propyl)-4H-pyrido[2,3-b]pyrazin-3-one;
- 4-(3-{[(R)-3-(2,3-dihydro-benzo[1,4]dioxin-6-yl)-2-oxo-oxazolidin-5-ylmethyl]-amino}-propyl)-6-methoxy-4H-pyrido[2,3-b]pyrazin-3-one;
- 6-methoxy-4-(3-{[(R)-2-oxo-3-(3-oxo-3,4-dihydro-2H-benzo[1,4]oxazin-6-yl)-oxazolidin-5-ylmethyl]-amino}-propyl)-4H-pyrido[2,3-b]pyrazin-3-one;
- 6-methoxy-4-(2-{2-[(R)-2-oxo-3-(3-oxo-3,4-dihydro-2H-benzo[1,4]thiazin-6-yl)-oxazolidin-5-yl]-ethylamino}-ethyl)-4H-pyrido[2,3-b]pyrazin-3-one;
- 6-methoxy-4-(2-{2-[(R)-2-oxo-3-(3-oxo-3,4-dihydro-2H-benzo[1,4]oxazin-6-yl)-oxazolidin-5-yl]-ethylamino}-ethyl)-4H-pyrido[2,3-b]pyrazin-3-one;
- 6-methoxy-4-(1-{2-[(R)-2-oxo-3-(3-oxo-3,4-dihydro-2H-benzo[1,4]thiazin-6-yl)-oxazolidin-5-yl]-ethyl}-azetidin-3-yl)-4H-pyrido[2,3-b]pyrazin-3-one;
- 6-methoxy-4-(1-{3-[(R)-2-oxo-3-(3-oxo-3,4-dihydro-2H-benzo[1,4]thiazin-6-yl)-oxazolidin-5-yl]-propyl}-azetidin-3-yl)-4H-pyrido[2,3-b]pyrazin-3-one;
- 6-methoxy-4-(1-{2-[(S)-2-oxo-3-(3-oxo-3,4-dihydro-2H-benzo[1,4]thiazin-6-yl)-oxazolidin-5-yl]-ethyl}-azetidin-3-yl)-4H-pyrido[2,3-b]pyrazin-3-one;
- 4-((R)-2-hydroxy-3-{[(R)-2-oxo-3-(3-oxo-3,4-dihydro-2H-benzo[1,4]thiazin-6-yl)-oxazolidin-5-ylmethyl]-amino}-propyl)-6-methoxy-4H-pyrido[2,3-b]pyrazin-3-one;
- 4-((R)-3-{[(R)-3-(2,3-dihydro-benzo[1,4]dioxin-6-yl)-2-oxo-oxazolidin-5-ylmethyl]-amino}-2-hydroxy-propyl)-6-methoxy-4H-pyrido[2,3-b]pyrazin-3-one;
- 4-((R)-2-hydroxy-3-{[(R)-2-oxo-3-(3-oxo-3,4-dihydro-2H-benzo[1,4]oxazin-6-yl)-oxazolidin-5-ylmethyl]-amino}-propyl)-6-methoxy-4H-pyrido[2,3-b]pyrazin-3-one; and
- 1-(3-{[(R)-3-(2,3-dihydro-benzo[1,4]dioxin-6-yl)-2-oxo-oxazolidin-5-ylmethyl]-amino}-propyl)-7-methoxy-3,4-dihydro-1H-quinolin-2-one.
45) In addition to the compounds listed in embodiments 43) and 44), further preferred
compounds of Formula (I) as defined in embodiment 1) are selected from the group consisting
of:
- 4-(3-{[(R)-3-(3-fluoro-4-methyl-phenyl)-2-oxo-oxazolidin-5-ylmethyl]-amino}-propyl)-6-methoxy-4H-pyrido[2,3-b]pyrazin-3-one;
- 6-methoxy-4-{1-[(R)-2-oxo-3-(3-oxo-3,4-dihydro-2H-benzo[1,4]thiazin-6-yl)-oxazolidin-5-ylmethyl]-azetidin-3-yl}-4H-pyrido[2,3-b]pyrazin-3-one;
- 4-(2-{2-[3-(2,3-dihydro-[1,4]dioxino[2,3-c]pyridin-7-yl)-2-oxo-oxazolidin-5-yl]-ethylamino}-ethyl)-6-methoxy-4H-pyrido[2,3-b]pyrazin-3-one;
- 4-(2-{2-[3-(2,3-dihydro-[1,4]dioxino[2,3-b]pyridin-6-yl)-2-oxo-oxazolidin-5-yl]-ethylamino}-ethyl)-6-methoxy-4H-pyrido[2,3-b]pyrazin-3-one;
- 6-(5-{2-[2-(6-methoxy-3-oxo-3H-pyrido[2,3-b]pyrazin-4-yl)-ethylamino]-ethyl}-2-oxo-oxazolidin-3-yl)-4H-pyrido[3,2-b][1,4]oxazin-3-one;
- 4-(1-{2-[(R)-3-(4-ethoxy-phenyl)-2-oxo-oxazolidin-5-yl]-ethyl}-azetidin-3-yl)-6-methoxy-4H-pyrido[2,3-b]pyrazin-3-one; and
- 6-methoxy-2-methyl-4-(3-{[(R)-2-oxo-3-(3-oxo-3,4-dihydro-2H-benzo[1,4]thiazin-6-yl)-oxazolidin-5-ylmethyl]-amino}-propyl)-4H-pyrido[2,3-b]pyrazin-3-one.
46) The invention further relates to compounds of Formula (I) according to embodiment
1) which are also compounds of formula (IP1)

wherein
R1 represents (C1-C4)alkoxy or halogen;
U represents CH or N;
V represents CH;
W represents CH or N;
A represents -CH2-CH(R2)-B-NH-* or -CH(R3)-CH2-N(R4)-CH2-*; wherein the asterisks indicate the bond which is linked via the CH2-group to the oxazolidinone moiety;
R2 represents hydrogen, OH or NH2;
R3 and R4 together represent CH2;
B represents CH2 or CO; and
G represents 6,7-dihydro-[1,4]dioxino[2,3-c]pyridazin-3-yl; or


wherein
M and Z1 represent CH or N; and
Q and Q' independently represent S or O;
wherein the preferences or embodiments indicated for the compounds of Formula (I)
(whether for the compounds themselves, salts thereof, compositions containing the
compounds or salts thereof, uses of the compounds or salts thereof, etc.) apply mutatis mutandis to compounds of formula (IP).
47) A particular embodiment of this invention relates to compounds of Formula (I)
as defined in embodiment 1) except that R1b represents H and m, if present, represents 1 or 2; as well as to the salts, especially
the pharmaceutically acceptable salts, of the compounds of Formula (I). The preferences
and embodiments mentioned for the compounds of Formula (I) in embodiments 2) to 40)
apply mutatis mutandis to the present embodiment.
48) The invention further relates to compounds of Formula (I) according to embodiment
47) which are also compounds of formula (ICEP2)

wherein
R1 represents (C1-C4)alkoxy (especially methoxy) or halogen (especially bromine);
"----" is absent, U, and V each represent CH, and W represents CH2; or
"-----" is a bond; and
U, V and W each represent CH; or U and V each represent CH and W represents N; or U and W each represent N and V represents CH;
A represents -CH2-CH(R2)-B-NH-* or -CH(R3)-CH2-N(R4)-[CH2]m-*, wherein the asterisks indicate the bond which is linked via the CH2-group to the oxazolidinone moiety; B represents CH2 or CO; and
R2 represents hydrogen, OH or NH2;
R3 and R4 both represent hydrogen and m represents the integer 1; or R3 and R4 together form a methylene bridge and m represents the integer 1 or 2; and
G represents a group selected from the group consisting of 2,3-dihydro-benzo[1,4]dioxin-6-yl,
3-oxo-3,4-dihydro-2H-benzo[1,4]oxazin-6-yl, 3-oxo-3,4-dihydro-2H-benzo[1,4]thiazin-6-yl, and 7-fluoro-3-oxo-3,4-dihydro-2H-benzo[1,4]thiazin-6-yl;
wherein the preferences or embodiments indicated for the compounds of Formula (I)
in embodiments 2) to 40) (whether for the compounds themselves, salts thereof, compositions
containing the compounds or salts thereof, uses of the compounds or salts thereof,
etc.) apply mutatis mutandis to compounds of formula (ICEP2).
49) The invention also relates to compounds of Formula (I) as defined in embodiment
1) which are also compounds of formula (ICE)

wherein
R1 represents (C1-C4)alkoxy (especially methoxy) or halogen (especially bromine);
"-----" is absent, U, and V each represent CH, and W represents CH2; or
"-----" is a bond; and
U, V and W each represent CH; or U and V each represent CH and W represents N; or U and W each represent N and V represents CH;
A represents -CH2-CH(R2)-B-NH-* or -CH(R3)-CH2-N(R4)[CH2]m-*; wherein the asterisks indicate the bond which is linked via the CH2-group to the oxazolidinone moiety;
B represents CH2 or CO; and
R2 represents hydrogen, OH or NH2;
R3 and R4 both represent hydrogen and m represents the integer 1; or R3 and R4 together form a methylene bridge and m represents the integer 1 or 2; and
G represents phenyl which is mono-substituted in position 3 by (C1-C3)alkoxy (notably ethoxy), or G represents phenyl which is disubstituted in positions 3 and 4, whereby one of the
two substituents is halogen (notably fluorine) and the other is (C1-C4)alkyl (notably methyl); or also
G represents a group selected from the group consisting of the groups G1, and G5 drawn below:

wherein
each of Z1 and Z2 represents CH, or one of Z1 and Z2 represents N and the other represents CH;
M represents CH or N;
Q and Q' independently represent S or O;
R5 represents hydrogen or fluorine;
wherein the preferences or embodiments indicated for the compounds of Formula (I)
in embodiments 2) to 42) (whether for the compounds themselves, salts thereof, compositions
containing the compounds or salts thereof, uses of the compounds or salts thereof,
etc.) apply mutatis mutandis to compounds of formula (ICE).
50) The invention further relates to compounds of Formula (I) as defined in embodiment
1), embodiment 2), embodiment 3) or embodiment 49) wherein G represents a group selected
from the group consisting of 3-fluoro-4-methyl-phenyl, 4-ethoxy-phenyl, 2,3-dihydro-benzo[1,4]dioxin-6-yl,
2,3-dihydro-[1,4]dioxino[2,3-c]pyridin-7-yl, 2,3-dihydro-[1,4]dioxino[2,3-b]pyridin-6-yl, 3-oxo-3,4-dihydro-2H-benzo[1,4]oxazin-6-yl, 3-oxo-3,4-dihydro-2H-pyrido[3,2-b][1,4]oxazine-6-yl, 3-oxo-3,4-dihydro-2H-benzo[1,4]thiazin-6-yl and 7-fluoro-3-oxo-3,4-dihydro-2H-benzo[1,4]thiazin-6-yl.
[0020] The compounds of Formula (I) according to one of embodiments 1) to 50) may contain
one or more stereogenic or asymmetric centers, such as one or more asymmetric carbon
atoms. The compounds of Formula (I) may thus be present as mixtures of stereoisomers
or preferably as pure stereoisomers. Mixtures of stereoisomers may be separated in
a manner known to a person skilled in the art.
[0021] Where the plural form is used for compounds, salts, pharmaceutical compositions,
diseases or the like, this is intended to mean also a single compound, salt, disease
or the like.
[0022] The compounds of Formula (I) according to one of embodiments 1) to 50) are suitable
for the use as chemotherapeutic active compounds in human and veterinary medicine
and as substances for preserving inorganic and organic materials in particular all
types of organic materials for example polymers, lubricants, paints, fibres, leather,
paper and wood.
[0023] These compounds according to the invention are particularly active against bacteria
and bacteria-like organisms. They are therefore particularly suitable in human and
veterinary medicine for the prophylaxis and chemotherapy of local and systemic infections
caused by these pathogens as well as disorders related to bacterial infections comprising
pneumonia, otitis media, sinusitis, bronchitis, tonsillitis, and mastoiditis related
to infection by
Streptococcus pneumoniae, Haemophilus influenzae, Moraxella catarrhalis, Staphylococcus
aureus, Enterococcus faecalis, E. faecium, E. casseliflavus, S. epidermidis, S. haemolyticus, or
Peptostreptococcus spp.; pharyngitis, rheumatic fever, and glomerulonephritis related to infection by Streptococcus
pyogenes, Groups C and G streptococci,
Corynebacterium diphtheriae, or
Actinobacillus haemolyticum; respiratory tract infections related to infection by
Mycoplasma pneumoniae, Legionella pneumophila, Streptococcus pneumoniae, Haemophilus
influenzae, or
Chlamydia pneumoniae; blood and tissue infections, including endocarditis and osteomyelitis, caused by
S.
aureus, S. haemolyticus, E. faecalis, E. faecium, E. durans, including strains resistant to known antibacterials such as, but not limited to,
beta-lactams, vancomycin, aminoglycosides, quinolones, chloramphenicol, tetracyclines
and macrolides; uncomplicated skin and soft tissue infections and abscesses, and puerperal
fever related to infection by
Staphylococcus aureus, coagulase-negative staphylococci (i.e.,
S. epidermidis, S. haemolyticus, etc.),
Streptococcus pyogenes, Streptococcus agalactiae, Streptococcal groups C-F (minute colony streptococci), viridans streptococci,
Corynebacterium minutissimum, Clostridium spp., or
Bartonella henselae; uncomplicated acute urinary tract infections related to infection by
Staphylococcus aureus, coagulase-negative staphylococcal species, or Enterococcus spp.; urethritis and cervicitis;
sexually transmitted diseases related to infection by
Chlamydia trachomatis, Haemophilus ducreyi, Treponema pallidum, Ureaplasma urealyticum, or
Neiserria gonorrheae; toxin diseases related to infection by S.
aureus (food poisoning and toxic shock syndrome), or Groups A, B, and C streptococci; ulcers
related to infection by
Helicobacter pylori; systemic febrile syndromes related to infection by
Borrelia recurrentis; Lyme disease related to infection by
Borrelia burgdorferi; conjunctivitis, keratitis, and dacrocystitis related to infection by
Chlamydia trachomatis, Neisseria gonorrhoeae, S. aureus, S. pneumoniae, S. pyogenes,
H. influenzae, or
Listeria spp.; disseminated
Mycobacterium avium complex (MAC) disease related to infection by
Mycobacterium avium, or
Mycobacterium intracellulare; infections caused by
Mycobacterium tuberculosis, M. leprae, M. paratuberculosis, M. kansasii, or
M. chelonei; gastroenteritis related to infection by
Campylobacter jejuni; intestinal protozoa related to infection by
Cryptosporidium spp.; odontogenic infection related to infection by viridans streptococci; persistent
cough related to infection by
Bordetella pertussis; gas gangrene related to infection by
Clostridium perfringens or
Bacteroides spp.; and atherosclerosis or cardiovascular disease related to infection by
Helicobacter pylori or
Chlamydia pneumoniae.
[0024] The compounds of Formula (I) according to one of embodiments 1) to 50 are further
useful for the preparation of a medicament for the treatment of infections that are
mediated by bacteria such as
E. coli, Klebsiella pneumoniae and other Enterobacteriaceae,
Acinetobacter spp., Stenothrophomonas maltophilia, Neisseria meningitidis, Bacillus
cereus, Bacillus anthracis, Clostridium difficile, Corynebacterium spp., Propionibacterium acnes and
bacteroide spp.
[0025] The compounds of Formula (I) according to one of embodiments 1) to 50 are further
useful to treat protozoal infections caused by
Plasmodium malaria, Plasmodium falciparum, Toxoplasma gondii, Pneumocystis carinii,
Trypanosoma brucei and
Leishmania spp.
[0026] The present list of pathogens is to be interpreted merely as examples and in no way
as limiting.
[0027] The compounds of Formula (I) according to one of embodiments 1) to 50), or the pharmaceutically
acceptable salts thereof, may be used for the preparation of a medicament, and are
suitable, for the prevention or treatment of a bacterial infection.
[0028] One aspect of this invention therefore relates to the use of a compound of Formula
(I) according to one of embodiments 1) to 50), or of a pharmaceutically acceptable
salt thereof, for the manufacture of a medicament for the prevention or treatment
of a bacterial infection. Another aspect of this invention relates to a compound of
Formula (I) according to one of embodiments 1) to 50), or of a pharmaceutically acceptable
salt thereof, for the prevention or treatment of a bacterial infection.
[0029] Accordingly, the compounds of Formula (I) according to one of embodiments 1) to 50),
or the pharmaceutically acceptable salts thereof, may be used for the preparation
of a medicament, and are suitable, for the prevention or treatment of a bacterial
infection selected from the group consisting of respiratory tract infections, otitis
media, meningitis, skin and soft tissue infections (whether complicated or uncomplicated),
pneumonia (including hospital acquired pneumonia), bacteremia, endocarditis, intraabdominal
infections, gastrointestinal infections,
Clostridium difficile infections, urinary tract infections, sexually transmitted infections, foreign body
infections, osteomyelitis, lyme disease, topical infections, opthalmological infections,
tuberculosis and tropical diseases (e.g. malaria), and notably for the prevention
or treatment of a bacterial infection selected from the group consisting of respiratory
tract infections, otitis media, meningitis, skin and soft tissue infections (whether
complicated or uncomplicated), pneumonia (including hospital acquired pneumonia) and
bacteremia.
[0030] As well as in humans, bacterial infections can also be treated using compounds of
Formula (I) according to one of embodiments 1) to 50) (or pharmaceutically acceptable
salts thereof) in other species like pigs, ruminants, horses, dogs, cats and poultry.
[0031] The present invention also relates to pharmacologically acceptable salts and to compositions
and formulations of compounds of Formula (I) according to one of embodiments 1) to
50).
[0032] Any reference to a compound of Formula (I) according to one of embodiments 1) to
50) is to be understood as referring also to the salts (and especially the pharmaceutically
acceptable salts) of such compounds, as appropriate and expedient.
[0034] A pharmaceutical composition according to the present invention contains at least
one compound of Formula (I) according to one of embodiments 1) to 50) (or a pharmaceutically
acceptable salt thereof) as the active agent and optionally carriers and/or diluents
and/or adjuvants, and may also contain additional known antibiotics.
[0035] As mentioned above, therapeutically useful agents that contain compounds of Formula
(I) according to one of embodiments 1) to 50), their salts and formulations thereof
are also comprised in the scope of the present invention.
[0036] The compounds of Formula (I) according to one of embodiments 1) to 50) and their
pharmaceutically acceptable salts can be used as medicaments, e.g. in the form of
pharmaceutical compositions for enteral or parental administration.
[0037] The production of the pharmaceutical compositions can be effected in a manner which
will be familiar to any person skilled in the art (see for example
Remington, The Science and Practice of Pharmacy, 21st Edition (2005), Part 5, "Pharmaceutical
Manufacturing" [published by Lippincott Williams & Wilkins]) by bringing the described compounds of Formula (I) or their pharmaceutically acceptable
salts, optionally in combination with other therapeutically valuable substances, into
a galenical administration form together with suitable, non-toxic, inert, therapeutically
compatible solid or liquid carrier materials and, if desired, usual pharmaceutical
adjuvants.
[0038] Moreover, the compounds of Formula (I) according to one of embodiments 1) to 50)
may also be used for cleaning purposes, e.g. to remove pathogenic microbes and bacteria
from surgical instruments or to make a room or an area aseptic. For such purposes,
the compounds of formula (I) could be contained in a solution or in a spray formulation.
[0039] Unless used regarding temperatures, the terms "about" placed before a numerical value
"X" refers in the current application to an interval extending from X minus 10% of
X to X plus 10% of X, and preferably to an interval extending from X minus 5% of X
to X plus 5% of X. In the particular case of temperatures, the term "about" placed
before a temperature "Y" refers in the current application to an interval extending
from the temperature Y minus 10°C to Y plus 10°C, and preferably to an interval extending
from Y minus 5°C to Y plus 5°C. Besides, the term "room temperature" (rt) as used
herein refers to a temperature of 25°C.
PREPARATION OF COMPOUNDS OF FORMULA (I)
Abbreviations:
[0040] The following abbreviations are used throughout the specification and the examples:
| AcOH |
acetic acid |
| AD-mix α |
1,4-bis(dihydroquinine)phthalazine, K3Fe(CN)6, K2CO3 and K2OsO4.2H2O |
| AD-mix β |
1,4-bis(dihydroquinidine)phthalazine, K3Fe(CN)6, K2CO3 and K2OsO4.2H2O |
| aq. |
aqueous |
| Boc |
tert-butoxycarbonyl- |
| n-BuLi |
n-butyl lithium |
| t-BuOH |
tert-butanol |
| Cbz |
benzyloxycarbonyl- |
| CDI |
1,1'-carbonyldiimidazole |
| d |
day(s) |
| DCM |
dichloromethane |
| DCC |
N,N'-dicyclohexylcarbodiimide |
| DCE |
1,2-dichloroethane |
| DIBAH |
diisobutylaluminium hydride |
| DIPEA |
N,N-diisopropylethylamine |
| DMAP |
4-dimethylaminopyridine |
| DMF |
N,N-dimethylformamide |
| DMSO |
dimethylsulfoxide |
| DPEphos |
bis(2-diphenylphosphinophenyl)ether |
| DPPA |
diphenyl phosphoryl azide |
| EA |
ethyl acetate |
| EDC |
1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride |
| eq. |
equivalent(s) |
| ESI |
Electron Spray Ionisation |
| Et |
ethyl |
| ether |
diethylether |
| EtOH |
ethanol |
| Et3SiH |
triethylsilane |
| CC |
column chromatography over silica gel |
| h |
hour(s) |
| HATU |
(O-(7-azabenzotriazol-1-yl)-1,1,3,3-tetramethyl-uronium hexafluorphoshate |
| Hept |
heptane |
| hex |
hexane |
| HOBT |
hydroxybenzotriazole |
| KHMDS |
potassium bis(trimethylsilyl)amide |
| LiOtBu |
lithium tert-butoxide |
| Me |
methyl |
| MeCN |
acetonitrile |
| MeOH |
methanol |
| min |
minutes |
| Ms |
methanesulfonyl- (mesyl-) (as in MsCl: methanesulfonyl chloride) |
| MS |
Mass Spectroscopy |
| Ms2O |
methansulfonic acid anhydride |
| NaBH(OAc)3 |
sodium triacetoxyborohydride |
| NaOMe |
sodium methylate |
| NMO |
N-methylmorpholine N-oxide |
| OAc |
acetate |
| org. |
organic |
| Pd/C |
palladium on carbon |
| Pd(OH)2/C |
palladium dihydroxide on carbon |
| PPh3 |
triphenylphosphine |
| Pyr |
pyridine |
| quant. |
quantitative |
| Rochelles salt |
potassium sodium tartrate |
| rt |
room temperature |
| sat. |
saturated |
| TBAF |
tetrabutylammonium fluoride |
| TBDMS |
tert-butyldimethylsilyl- |
| TBDPS |
tert-butyldiphenylsilyl- |
| TBME |
tert-butylmethyl ether |
| TEA |
triethylamine |
| TEMPO |
2,2,4,4-tetramethylpiperidine 1-oxyl |
| Tf |
trifluoromethanesulfonyl-(as in TfCl: trifluoromethanesulfonyl chloride) |
| Tf2O |
trifluoromethanesulfonic acid anhydride |
| TFA |
trifluoroacetic acid |
| THF |
tetrahydrofuran |
| Ts |
p-toluenesulfonyl- (tosyl-) (as in p-TsCl: p-toluenesulfonyl chloride) |
General synthetic methods:
General synthetic method 1: activation of an alcohol:
[0041] The alcohol derivative is reacted with MsCl, TfCl, TsCl in presence of an organic
base such as TEA, DIPEA or pyridine in a solvent such as DCM, THF or pyridine between
-10°C and 25°C. Alternatively the alcohol can also be reacted with Ms
2O or Tf
2O. The activated intermediate can be further transformed into its corresponding iodo
or bromo derivative by reaction of the activated alcohol with NaI or NaBr in a solvent
such as acetone.
General synthetic method 2: alkylation:
[0042] The amine derivative is reacted with a compound of formula alkyl-L
1, VI, XII or XIV wherein L
1, L
2 and L
3 represent OMs, OTf, OTs, Cl, Br or I in presence of an inorganic base such as K
2CO
3, CsCO
3 or an organic base such as TEA in a solvent such as THF, DMF or DMSO, between 0°C
and +80°C. Further details can be found in
Comprehensive Organic Transformations. A guide to Functional Group Preparations; 2nd
Edition, R. C. Larock, Wiley-VC; New York, Chichester, Weinheim, Brisbane, Singapore,
Toronto, (1999). Section Amines p.779.
General synthetic method 3: reductive amination:
[0043] A solution of primary amine (1 mmol) and aldehyde or ketone (1 mmol) in DCE/MeOH
1:1 (10 mL) is stirred at rt overnight. NaBH
4 (2-5 eq.) is added and the reaction allowed to proceed for another one hour. The
reaction is diluted with DCM and aq. NH
4OH. The org. phase is washed with water, dried over MgSO
4 and concentrated. Alternatively, a solution of secondary amine (1 mmol) and aldehyde
or ketone (1 mmol) in DCE/MeOH 1:1 (10 mL) is treated with NaBH(OAc)
3 (2 eq). The mixture is stirred at rt until complete conversion. The reaction is diluted
with DCM and aq. NH
4OH. The org. phase is washed with water, dried over MgSO
4 and concentrated.
General_synthetic method 4: amide coupling:
[0044] The carboxylic acid is reacted with the amine in presence of an activating agent
such as DCC, EDC, HOBT, n-propylphosphonic cyclic anhydride, HATU or di-(
N-succinimidyl)-carbonate, in a dry aprotic solvent such as DCM, MeCN or DMF between
-20°C and +60°C (see
G. Benz in Comprehensive Organic Synthesis, B.M. Trost, I. Fleming, Eds; Pergamon
Press: New York (1991), vol. 6, p. 381). Alternatively, the carboxylic acid can be activated by conversion into its corresponding
acid chloride by reaction with oxalyl chloride or thionyl chloride neat or in a solvent
like DCM between -20° and +60°C. Further activating agents can be found in
Comprehensive Organic Transformations. A guide to Functional Group Preparations; 2nd
Edition, R. C. Larock, Wiley-VC; New York, Chichester, Weinheim, Brisbane, Singapore,
Toronto, 1999. Section nitriles, carboxylic acids and derivatives p.1941-1949.
General_synthetic method 5: cis-dihydroxylation:
[0045] The diol is obtained by dihydroxylation of the corresponding ethylenic derivative
using a catalytic amount of osmium tetroxide in the presence a co-oxidant such as
NMO in aq. solvent such as an acetone - water or DCM - water mixture (see
Cha, J.K. Chem. Rev. 1995, 95, 1761-1795). The chiral cis-diols are obtained by using AD-mix α or AD-mix β in presence of
methanesulfonamide in a water/2-methyl-2-propanol mixture as described in
Chem. Rev. (1994), 94, 2483. The sense of induction relies on the chiral ligand contained in the AD mixture,
either a dihydroquinine-based ligand in AD-mix α or a dihydroquinidine-based ligand
in AD-mix β.
General_synthetic method 6: alcohols throuh ester reduction:
[0046] The ester is reduced with a boron or aluminium hydride reducing agent such as LiBH
4 or LiAlH
4 in a solvent such as THF between -20°C and 40°C. Alternatively, the ester function
is hydrolyzed into its corresponding acid using an alkali hydroxide such as NaOH,
KOH or LiOH in water or in a mixture of water with polar protic or aprotic organic
solvent such as THF or MeOH between -10°C and 50°C. The resulting carboxylic acid
is further reduced into the corresponding alcohol using a borane derivative such as
a BH
3.THF complex in a solvent such as THF between -10°C and 40°C.
General synthetic method 7: aldehydes through ester reduction:
[0047] The ester is reduced with a bulky hydride reagent DIBAH in a solvent such as THF
between -20°C and 40°C.
General_synthetic method 8: hydrolysis of ester into carboxylic acids:
[0048] When the ester side chain is a linear alkyl, the hydrolysis is usually performed
by treatment with an alkali hydroxide such as LiOH, KOH or NaOH in a water-dioxane
or water - THF mixture between 0°C and +80°C. When the ester side chain is tert-butyl,
the hydrolysis can also be performed in neat TFA or diluted TFA or HCl in an organic
solvent such as ether or THF. When the ester side chain is the allyl group, the reaction
is performed in presence of tetrakis(triphenylphosphine)palladium(0) in presence of
an Π-allyl cation scavenger such as morpholine, dimedone or tributyltin hydride between
0°C and +50°C in a solvent such as THF. When the ester side chain is benzyl, the reaction
is performed under hydrogen in presence of a noble metal catalyst such as Pd/C in
a solvent such as MeOH, THF or EA. Further strategies to introduce other acid protecting
groups and general methods to remove them have been described in
Protecting Groups in Organic Synthesis 3rd Ed; 1999, 369-441; T.W.Greene, P.G.M. Wuts;
(Publisher: John Wiley and Sons, Inc., New York, N.Y.).
General_ synthetic method 9: amino deprotection:
General synthetic method 10: hydroxy deprotection:
[0050] The silyl ether groups are removed either using fluoride anion sources such as TBAF
in THF between 0°C and +40°C or HF in MeCN between 0°C and +40°C or using acidic conditions
such as AcOH in THF/MeOH or HCl in MeOH. Further methods to remove the TBDMS and TBDPS
groups are given in
Protecting Groups in Organic Synthesis 3rd Ed; 1999, 133-139 and 142-143 respectively;
T.W.Greene, P.G.M. Wuts; (Publisher: John Wiley and Sons, Inc., New York, N.Y.). Further general methods to remove alcohol protecting groups are described in
Protecting Groups in Organic Synthesis 3rd Ed; 1999, 23-147; T.W.Greene, P.G.M. Wuts;
(Publisher: John Wiley and Sons, Inc., New York, N.Y.).
General synthetic method 11: reduction of azides into amines:
[0051] The azides are hydrogenated over a noble metal catalyst such as Pd/C in solvent such
as MeOH or EA. In case the molecule is containing an unsaturated double or triple
bond, the reduction can be performed using PPh
3 in presence of water as described in
J. Med.Chem. (1993), 36, 2558-68.
General synthetic method 12: ketal deprotection:
[0052] The ketal is converted into its corresponding ketone under acidic conditions such
as diluted aq. HCl in MeOH, diluted aq. AcOH or by using an acidic resin such as Amberlite
IR120H or DOWEX 50W8 in a water-solvent mixture such as MeOH/water or THF/water.
The compounds of Formula (I) obtained according to the abovementioned general preparation
methods may then, if desired, be converted into their salts, and notably into their
pharmaceutically acceptable salts. Whenever the compounds of Formula (I) are obtained
in the form of mixtures of enantiomers, the enantiomers can be separated using methods
known to one skilled in the art: e.g. by formation and separation of diastereomeric
salts or by HPLC over a chiral stationary phase such as a Regis Whelk-O1(R,R) (10µm)
column, a Daicel ChiralCel OD-H (5-10 µm) column, or a Daicel ChiralPak IA (10 µm)
or AD-H (5µm) column. Typical conditions of chiral HPLC are an isocratic mixture of
eluent A (EtOH, in presence or absence of an amine such as TEA, diethylamine) and
eluent B (hex), at a flow rate of 0.8 to 150 mL/min.
General_synthetic method 13: oxidation of alcohols/aldehydes into acids:
[0053] Alcohols can be directly oxydized into their corresponding acids by a variety of
methods as described in
Comprehensive Organic Transformations. A guide to Functionnal Group Preparations;
2nd Edition, R. C. Larock, Wiley-VC; New York, Chichester, Weinheim, Brisbane, Singapore,
Toronto, 1999. Section nitriles, carboxylic acids and derivatives p.1646-1648. Among them, [bis(acetoxy)iodo]benzene
in presence of TEMPO, the Jones reagents (CrO
3/H
2SO
4), NaIO
4 in presence of RuCl
3, KMnO
4 or Pyr.H
2Cr
2O
7 are frequently used.
[0054] Aldehydes can be oxidized into their corresponding acids by a variety of methods
as described in
Comprehensive Organic Transformations. A guide to Functionnal Group Preparations;
2nd Edition, R. C. Larock, Wiley-VC; New York, Chichester, Weinheim, Brisbane, Singapore,
Toronto, 1999. Section nitriles, carboxylic acids and derivatives p.1653-1655. Among them, KMnO
4 in an acetone-water mixture (see
Synthesis (1987), 85) or sodium chlorite in 2-methyl-2-propanol in presence of 2-methyl-2-butene (see
Tetrahedron (1981), 37, 2091-2096) are frequently used.
General_synthetic method_14: protection of alcohols:
General synthetic method 15 (hydrogenation of a double bond):
[0056] The unsaturated derivatives dissolved in a solvent such as MeOH, EA or THF are hydrogenated
over a noble metal catalyst such as Pd/C or Pd(OH)
2/C, or over Raney Ni. At the end of the reaction the catalyst is filtered off and
the filtrate is evaporated under reduced pressure. Alternatively the reduction can
be performed by catalytic transfer hydrogenation using Pd/C and ammonium formate as
hydrogen source.
General preparation methods:
Preparation of the compounds of formula(I):
[0057] The compounds of Formula (I) can be manufactured by the methods given below, by the
methods given in the examples or by analogous methods. Optimum reaction conditions
may vary with the particular reactants or solvents used, but such conditions can be
determined by a person skilled in the art by routine optimisation procedures.
[0058] Sections a) to h) hereafter describe general methods for preparing compounds of Formula
(I). The preparation of elaborated intermediates and basic building blocks is described
thereafter. General synthetic methods used repeatedly throughout the schemes below
are referenced to and described in the end of this section. If not indicated otherwise,
the generic groups and integers U, V, W, R
1, R
2, R
3, R
4, A, B, G and m are as defined for Formula (I). Other abbreviations used are defined
in the experimental section. In some instances the generic groups R
1, R
2, R
3, R
4, A, B, W, and G might be incompatible with the assembly illustrated in the schemes
below and so will require the use of protecting groups (PG). The use of protecting
groups is well known in the art (see for example "
Protective Groups in Organic Synthesis", T.W. Greene, P.G.M. Wuts, Wiley-Interscience,
1999).
[0059] The compounds of Formula (I) can be manufactured in accordance with the present invention
using the procedures described hereafter by:
a) reacting the compounds of formula (II)

with the carbonic acid derivatives of formula (III),

wherein L0 and L00 both represent chloro, OCCl3, imidazolyl or succinimidyloxy, or L0 represents chloro and L00 represents OCCl3. This reaction is preferably carried out in a dry aprotic solvent such as DCM or
THF in presence of an organic base such as TEA or pyridine and at a temperature range
between -30°C and +80°C; or
b) reacting the compounds of formula (IV)

with the anions generated from the compounds of formula (V)

wherein R represents alkyl or benzyl, with a base such as KHMDS or lithium tert-butylate; or
c) reacting the compounds of formula (VI)

wherein L1 represents a halogen such as chlorine or bromine, or a OSO2Ra group wherein Ra is alkyl, tolyl, or trifluoromethyl with the compounds of formula (VII) following
general synthetic method 2

or
d) reacting the compounds of formula (VIII)

with the compounds of formula (VII) under reductive amination conditions following
general synthetic method 3; or
e) reacting a compound of formula (IX)

wherein R2 is H, OH or NH2 with a compound of formula (VII) following general synthetic method 4; or
f) reacting the compounds of formula (X) or (XI)

with the compounds of formula (XII)

wherein L2 represents a halogen such as iodine or bromine, or a OSO2Ra group wherein Ra is alkyl, tolyl, or trifluoromethyl and q represents the integer 1, 2 or 3, following
general synthetic method 2; or
g) reacting the compounds of formula (XIII)

with the compounds of formula (XIV)

wherein L3 represents a halogen such as iodine or bromine, or a OSO2Ra group wherein Ra is alkyl, tolyl, or trifluoromethyl, following general synthetic method 2; or
h) reacting the compounds of formula (XIII) with the compounds of formula (XV)

in presence of CsF in an organic solvent such as MeCN between 20 and 80°C; or
i) reacting the compounds of formula (XXX)

with the compounds of formula (XXXI)
G-X (XXXI)
wherein X represents halogen, whereby, in case of compounds of formula (XXXI) wherein
M is N, the reaction can be performed in presence of a NaH and this reaction can also
be performed under conditions described for the metal catalyzed N-arylation of 2-oxazolidinones or amides, in particular by using Cul and 1,1,1-tris(hydroxymethyl)ethane
in the presence of Cs2CO3 (Org. Lett. 2006, 8, 5609-5612), or Pd(OAc)2 and DPEphos in presence of K3PO4; or
j) deprotecting the compounds of formula (XXXII)

according to general synthetic method 10; or
k) deprotecting the compounds of formula (XXXIII)

wherein M is N or CH, Q' is O or S and PG0 represents a group such as 4-methoxybenzyl, 2,4-dimethoxybenzyl or 3,4-dimethoxybenzyl,
whereby said deprotection can be performed by treatment with TFA or cerium ammonium
nitrate.
[0060] The compounds of Formula (I) wherein "----" is absent can be obtained via hydrogenation
of compounds of Formula (I) wherein "----" is a bond over a noble catalyst such as
Pd/C (see for example general synthetic method 15) or via reduction of the same using
NaBH
4 in a solvent such as EtOH. Alternatively, appropriate intermediates described below
may be reduced as described above and transformed into the compounds of Formula (I)
according to methods a) to k) above.
Preparation of the compounds of formula (II):
[0061] The compounds of formula (II) can be obtained by reacting the compounds of formula
(IV) with the amines of formula (XVI)
G-NH
2 (XVI)
Preparation of the compounds of formula IV:
[0062] The compounds of formula (IV) can be obtained by cis-dihydroxylation of the compounds
of formula (XVII)

following general synthetic method 5 followed by mesylation or tosylation of the primary
alcohol function following general synthetic method 1 and epoxide formation under
basic conditions.
[0063] The compounds of formula (XVII) can be obtained as described in Scheme 1 hereafter.

[0064] The compounds of formula (XVII) wherein A represents -CH
2-CH
2-CH
2-NH-* can be obtained by reductive amination of the aldehydes of formula (VIII) with
the allyl amines of formula (Ia) following general synthetic method 3. The compounds
of formula (XVII) wherein A represents -CH
2-CH(R
2)-CO-NH-* can be obtained by amide coupling between the acids of formula (IX) with
the allyl amines of formula (Ia) following general synthetic method 4. The compounds
of formula (XVII) wherein A represents -CH
2-CH(R
2)-CH2-NH-* can be obtained by reductive amination of acroleine (Ib) with the amines
of formula (XI) following general synthetic method 3. The compounds of formula (XVII)
wherein A represents -CH(R
3)-CH
2-N(R
4)-CH
2-* and R
3 and R
4 together form a methylene bridge are obtained by substitution of the compounds of
formula (XIII) with the iodo derivative of formula (Ic) following general synthetic
method 2. Alternative conditions are NaH, K
2CO
3 or Ag
2CO
3 in a solvent such as DMF (see for example
Heteroat. Chem., 17, 2006, 280-288,
Bioorg. Med. Chem. Lett.,16, 2006, 658-662 or
J. Heterocycl. Chem., 42, 2005, 883-888).
Preparation of the compounds of formulae (VI), (VIII) and (IX):
[0065] The compounds of formulae (VI), (VIII) and (IX) can be obtained according to Scheme
2 hereafter.

[0066] In Scheme 2, R represents alkyl or benzyl, PG represents an amino protecting group
such as Cbz or Boc and L
1 represents OH, halogen such as bromine or OSO
2R
a wherein R
a is methyl, trifluoromethyl or tolyl.
[0067] The compounds of formula (IIb) can be obtained by CsF catalyzed addition of the derivatives
of formula (XIII) on the acrylic ester derivatives of formula (IIa). These esters
can be reduced into the corresponding alcohols of formula (VI) wherein L
1 is OH either directly following general synthetic method 6 or via the aldehydes of
formula (VIII). The alcohols of formula (VI) wherein L
1 is OH can be transformed into the corresponding mesylates, triflates, tosylates or
halogenides (L
1= OMs, OTf, OTs, Br, Cl or I) following general synthetic method 1. The compounds
of formula (IX) wherein R
2 is H can be obtained by hydrolysis of the esters of formula (IIb) following general
synthetic method 8. The compounds of formula (IX) wherein R
2 is NH
2 can be obtained by CsF catalyzed addition of the derivatives of formula (XIII) on
the acrylic ester derivatives of formula (IIc), followed by hydrolysis of the corresponding
esters into the corresponding carboxylic acids following general synthetic method
8 and removal of the amino protecting group following general synthetic method 9.
[0068] In the particular case wherein U and W each represent N, V represents CH and R
1b represents methyl, the compounds of formula (VIII) can also be prepared by oxidation
of the compounds of formula (VIIIg)

which oxidation can for example be carried out using Swem conditions and the like
(e.g. Pyr.SO
3 complex in DMSO in the presence of a base such as DIPEA).
[0069] Likewise, in the particular case wherein U and W each represent N, V represents CH
and R
1b represents methyl, the compounds of formula (IX) can also be prepared by ester hydrolysis
and, if required, removal of the amino or hydroxy protecting group of the compounds
of formula (VIIIf)

wherein R
2a represents H, NHPG
7 or OPG
8 and R
4 represents alkyl or benzyl.
Preparation of the compounds of formulae (X) and (XI):
[0070] The compounds of formula (X) and (XI) can be prepared as described in Scheme 3 hereafter.

[0071] In Scheme 3, PG
2 and PG
3 represent independently from each other an amino protecting group such as Boc or
Cbz, X
a represents a halogen, L
4 represents SO
2CF
3 and R represents alkyl or benzyl.
[0072] The compounds of formula (XI) can be obtained by reaction of the derivatives of formula
(XIII) with the intermediates of formula (IIIa), followed by removal of the amino
protecting group of the intermediates of formula (IIIb). The compounds of formula
(X) can be obtained by alkylation of the derivatives of formula (XIII) with
tert-butyl 3-iodo-1-azetidinecarboxylate (IIIc) following general synthetic method 2,
followed by removal of the amino protecting group of the intermediates of formula
(IIId) following general synthetic method 9.
[0073] Alternatively the compounds of formula (IIId) wherein V is CH and W is N can be obtained
from the known nitro derivatives of formula (IIIe) by reaction with known azetidine
derivatives of formula (IIIf) in presence of a base such as K
2CO
3 between 80 and 150°C in analogy to
US 5,245,037. The nitro derivative is converted into the corresponding amine derivative by reduction
(e.g hydrogenation over Pd/C) followed by reaction with an alkyl glyoxylate. The compounds
of formula (IIId) wherein V is CH and W is CH can be obtained from the derivatives
of formula (IIIi) after sequential ring opening under basic condition, esterification
of the carboxylic acid function and formation of the corresponding triflates of formula
(IIIj). These triflates can then be reacted in analogy to
Tetrahedron Letters (2003), 44(22), 4207-4211 with the azetidine derivatives of formula (IIIf), affording the corresponding derivatives
of formula (IIId).
[0074] In the particular case wherein U and W each represent N, V represents CH and R
1b represents methyl, the compounds of formula (XI) can also be prepared by removal
of the protecting group(s) of the compounds of formula (VIIIf)

wherein R
2a represents H, NHPG
7 or OPG
8 and PG
7 represents an amino protecting group such as Cbz, Fmoc or Boc.
Preparation of the compounds of formulae (VII), (XII), (XIV) and (XV):
[0075] The compounds of formulae (VII), (XII) (XIV) and (XV) can be prepared according to
Scheme 4 hereafter.

[0076] In Scheme 4, PG
5 represents an alcohol protecting group such as TBDMS, TBDPS; Y represents O or N-PG
6; PG
6 represents an amino protecting group such as Cbz or Boc; L
2 represents OH, OPG
5, halogen (such as bromine) or OSO
2R
a wherein R
a is methyl, trifluoromethyl or tolyl; and q represents the integer 1, 2 or 3.
[0077] The known epoxides of formula (IVa) can be transformed into the corresponding oxazolidinones
of formula (XII) wherein L
2 represents OPG
1 by reaction with the anions generated from the carbamates of formula (V) (see section
b) of part entitled "Preparation of the compounds of formula (I)"). The alcohol protecting
group can be removed following general synthetic method 10 and the intermediate alcohols
can be transformed following general synthetic method 1 into the corresponding compounds
of formula (XII) wherein L
2 represents halogen or OSO
2R
a, R
a being methyl, trifluoromethyl or tolyl. In the case wherein q is I, the corresponding
activated alcohols can be transformed into the corresponding amines of formula (VII)
after reaction with sodium azide and reduction into the corresponding amine following
general synthetic method 11. The amines of formula (VII) can be transformed into the
amides of formula (XV) by reaction with acrylic acid following general synthetic method
4. The amides of formula (XIV) wherein B = CO can be obtained by reaction of the amines
of formula (VII) with the known acids of formula (IVc) wherein Y is O or N-Boc, followed
by acidic treatment following general synthetic method 12 and activation of the primary
alcohol as a mesylate, tosylate, triflate or halogenide following general synthetic
method 1. The compounds of formula (XIV) wherein B is CH
2 can be obtained by reductive amination of the known aldehydes of formula (IVd) with
the amines of formula (VII) following general synthetic method 3, followed by acidic
treatment following general synthetic method 12 and activation of the primary alcohol
as a mesylate, tosylate, trifluoromethanesulfonate (triflate) or halogenide following
general synthetic method 1.
Preparation of the compounds of formula (XIII):
Preparation of the compounds of formulae (XVI):
[0079] The derivatives of formula G-NH
2 of formula (XVI) are commercially available or may be obtained from the known benzylic
alcohols of formula (Va) as described in Scheme 5 hereafter.

[0080] The known benzylic alcohols of formula (Va) can be oxidized into the corresponding
carboxylic acids following general synthetic method 13. The resulting carboxylic acids
of formula (Vb) can then be reacted with diphenylphosphoryl azide in the presence
of t-BuOH between 40° and 100°C, affording the carbamates of formula (Vc). The compounds
of formula (XVI; G-NH
2) are obtained following general synthetic method 9.
Preparation of the compounds of formula (XXX):
[0081] The intermediates of formula (XXX) can be obtained by reaction of the epoxides of
formula (IV) with sodium azide followed by hydrogenation over a noble metal catalyst
such as Pd/C and subsequent transformation into their corresponding carbamates with
CbzCl or Boc
2O. The oxazolidinone ring can then be formed by reaction with NaH.
Preparation of the compounds of formula (XXXI):
[0082] The derivatives of formula (XXXI) are commercially available (e.g. G = G
5, M = N, Q' = O and X = Cl: CAS 337463-99-7; G = G
5, M=CH, Q' = S and X = Cl: CAS 6376-70-1; G = G
5, M = CH, Q' = O and X = Cl: CAS 7652-29-1) or can be obtained according to known
literature procedures (
e.g. J. Org. Chem. (1990), 4744-59 for 7-chloro-1,8-naphthyridin-2(1
H)-one).
[0083] The particular compound of formula (XXXI) 6-chloro-4
H-pyrido[3,2-
b][1,4]thiazin-3-one can be obtained as described in Scheme 6.

[0084] The bromo derivative of formula (VIa), prepared according to
WO 2008/065198, can be reacted with bromoacetyl bromide and the resulting derivative of formula
(VIb) can be reacted with sodium thioacetate in presence of NaOMe to afford 6-chloro-4
H-pyrido[3,2-
b][1,4]thiazin-3-one.
Preparation of the compounds of formula (XXXII):
[0085] The intermediates of formula (XXXII) can be obtained after sequential protection
of the hydroxyl group of the compounds of formula (IIIb) (see Scheme 3), removal of
the amino protecting group according to general synthetic method 9 and reaction with
the intermediates of formula (XII) wherein q is 1 according to general reaction method
2.
Preparation of the compounds of formula (XXXIII):
[0086] The compounds of formula (XXXIII) can be prepared as summarised in Scheme 7 hereafter.

[0087] In Scheme 7, X
1 and X
2 each independently represent halogen such as bromine or chlorine and PG
0 represents (4-methoxyphenyl)methyl, (2,4-dimethoxyphenyl)methyl or (3,4-dimethoxyphenyl)methyl.
[0088] The compounds of formula (VIIa) are obtained by alkylation of compounds of formula
(XXXI) wherein G is G
5 and X is X
1 with the halogenides of formula PG
0-X
2 in the presence of a base such a Cs
2CO
3. The compounds of formula (XXXIII) can then be obtained in analogy to the method
of section i) of part entitled "Preparation of the compounds of formula (I)" by reacting
the compounds of formula (XXX) with the compounds of formula (VIIa).
Preparation of certain starting compounds:
[0089] The intermediate of formula (Ic) can be obtained by reacting 3-hydroxy azetidine
with 4-bromo-but-1-ene followed by activation of the alcohol function as a mesylate
following [general synthetic method 1] and reaction with NaI in acetone or from the
commercially available 2,3-dibromo-1-propanamine and homobenzylic bromide in analogy
to
Heterocycles (2002), 56(1-2), 433-442.
[0090] The enamines of formula (IIc) wherein R is Me and PG is Boc or Cbz are commercially
available (CAS 55477-80-0 and 21149-17-7).
[0091] The chloroalcohol derivatives of formula (IIIa) wherein PG is Boc or Cbz are commercially
available (CAS 641617-19-8, 641617-18-7 and 415684-05-8).
[0092] The compound of formula (IIIc) is commercially available (CAS 254454-54-1).
[0093] The compounds of formula (IIIi) are commercially available (R
1 = MeO: CAS 531-59-9) or prepared according to
EP 185319 (e.g. R
1 = F: CAS 71428-25-6).
[0094] The nitro derivatives of formula (IIIe) are commercially available (e.g. R
1 = OMe, U = CH and X
a = Br: CAS 98447-30-4; R
1 = OMe, U = N and X
a = Br: CAS 3442996-05-5; R'=F, U = CH and X
a = Br: CAS 700-36-7; R
1 = Cl, U = N and X
a = Cl: CAS 58602-02-1).
[0095] The azetidines of formula (IIIf) are commercially available (e.g. PG
1= Cbz or Boc: CAS 112257-20-2 and 193269-78-2).
[0096] The epoxides of formula (IVa) are commercially available (q = 1, PG
1= TBDMS: CAS 78906-15-7) or prepared according to known procedure (e.g. q = 3, PG
1= TBDMS:
EP 518672; q = 2, PG
1= TBDMS:
WO 2007/144423).
[0097] Compounds of formula (IVb) are commercially available (Y = NBoc: CAS 127589-93-9;
Y = O: CAS 5736-03-8).
[0098] Compounds of formula (IVc) are commercially available (Y = O: CAS 5736-06-1; Y =
NH: CAS 159585-65-6).
[0100] The compounds of formulae (VIIIf), (VIIIf) and (VIIIg) can be prepared as summarised
in Scheme 8 hereafter.

[0101] In Scheme 8, X
a represents halogen such as chlorine, R represents -(CH
2)
3-OPG
7 or -CH
2-(CHR
2a)-COOR
4, R
2a represents H, -OPG
8 or -NHPG
9, R
4 represents alkyl or benzyl, PG
7 and PG
8 each represent a hydroxy protecting group such as TBDMS and PG
9 represents an amino protecting group such as Cbz, Fmoc or Boc.
[0102] Accordingly, the compounds of formula (VIIIa) can be reacted with the intermediates
of formulae (VIIIb) or (VIIIc), affording the compounds of formula (VIIId) wherein
R is either -(CH
2)
3-OPG
7 or -CH
2-(CHR
2a)-COOR
4. The compounds of formula (VIIId) can then be reduced into the corresponding diamino
derivatives of formula (VIIIe). Said diamino derivatives can then be reacted with
alkyl pyruvate, affording the pyrido[2,3-b]pyrazin-3-one derivatives of formula (VIIIf)
or (VIIIf). The compounds of formula (VIIIf) can then be deprotected to yield the
compounds of formula (VIIIg).
[0103] The compounds of formulae (VIIIf) can be prepared as summarised in Scheme 8a hereafter.

[0104] In Scheme 8a, X
a represents halogen such as chlorine, R
2a represents H, -OPG
11 or -NHPG
12, PG
11 represents a hydroxy protecting group such as TBDMS and PG
10 and PG
12 each represent an amino protecting group such as Cbz, Fmoc or Boc.
[0105] Accordingly, the compounds of formula (VIIIa) can be reacted with the intermediates
of formulae (VIIIh), affording the compounds of formula (VIIIi). The compounds of
formula (VIIIi) can then be reduced into the corresponding diamino derivatives of
formula (VIIIj). Said diamino derivatives can then be reacted with alkyl pyruvate,
affording the pyrido[2,3-b]pyrazin-3-one derivatives of formula (VIIIf").
[0106] The intermediates of formulae (VIIIb), (VIIIc) and (VIIIh) are commercially available
(e.g. 3-amino-N-[(phenylmethoxy)carbonyl]-L-alanine
tert-butyl ester), or obtained according to literature procedures (e.g. (2S)-3-amino-2-[[(
tert-butyl)dimethylsilyl]oxy]-propanoic acid methyl ester:
Bioorg. Med. Chem. Lett. (2008), 18(3), 1058-1062;
N-[(
2S)-3-amino-2-[[(
tert-butyl)diphenylsilyl]oxy]propyl]-carbamic acid
tert-butyl ester:
J. Am. Chem. Soc. (2008), 130(6), 1836-1838).
Particular embodiments of the invention are described in the following examples, which
serve to illustrate the invention in more detail without limiting its scope in any
way.
EXPERIMENTAL SECTION
[0107] All temperatures are stated in °C. Compounds are characterized by
1H-NMR (300 MHz) (Varian Oxford); or by
1H-NMR (400 MHz) (Bruker Advance 400). Chemical shifts δ are given in ppm relative
to the solvent used; multiplicities: s = singlet, d = doublet, t = triplet, q = quadruplet,
p = pentuplet, hex = hexet, hep = heptet, m = multiplet, br = broad, coupling constants
are given in Hz. Alternatively compounds are characterized by LC-MS (Sciex API 2000
with Agilent 1100 Binary Pump with DAD and ELSD or an Agilent quadrupole MS 6140 with
Agilent 1200 Binary Pump, DAD and ELSD); by TLC (TLC-plates from Merck, Silica gel
60 F
254); or by melting point. Compounds are purified by chromatography on Silica gel 60A.
NH
4OH as used for CC is 25% aq.
[0108] The HPLC are done over a stationary phase such as a rapid resolution Zorbax SB C
18 (1.8 µm) column, or a rapid resolution Zorbax Eclipse Plus C18 (1.8 µm) column.
Typical conditions of HPLC are a gradient of eluent A (water: acetonitrile 95:5 with
0.1% of formic acid, in presence or not of 5 mmol/L ammonium formate) and eluent B
(acetonitrile: water 95:5 with 0.1% of formic acid, in presence or not of 5 mmol/L
ammonium formate), at a flow rate of 0.8 to 5 mL/min. Racemates can be separated into
their enantiomers as described before. Preferred conditions of chiral HPLC are: ChiralPak
AD (4.6 x 250 mm, 5 µm) column, using an isocratic mixture (eg. at a ratio of 10/90)
of eluent A (EtOH, in presence of diethylamine in an amount of eg. 0.1%) and eluent
B (Hex), at rt, at a flow rate of eg. 0.8 mL/min.
Procedures:
Procedure A: epoxide opening:
[0109] A solution of epoxide (1 mmol) and amine (1 mmol) in EtOH/H
2O (9:1, 1 to 5 mL) is heated at 80°C for 12 h. The volatiles are removed under reduced
pressure and the residue purified by chromatography by CC. In case the epoxide contains
a TBDMS group, the reaction may also be performed in MeCN in presence of 3 eq. LiClO
4.
Procedure B: oxazolidinone formation with CDI
[0110] A solution of the amino alcohol (1 mmol) and CDI (1-2 eq.) in THF (2 mL) is heated
at 50°C until completion of the reaction. The mixture is partitioned between EA (20
mL) and water (20 mL), the org. phase washed with brine (20 mL), dried over MgSO
4 and concentrated.
Procedure C: Cbz-protection of amines:
[0111] A mixture of amine (1 mmol), sat. aq. NaHCO
3 (2 mL) and acetone (2 mL) is treated dropwise with Cbz-Cl (1.05 eq.). After CO
2 evolvement ceased, the mixture is partitioned between EA and aq. bicarbonate, the
org. layer dried over MgSO
4 and concentrated.
Procedure D: Formation of a mesylate:
[0112] A solution of the alcohol (4 mmol) in DCM (20 mL) was cooled to 0°C. DIPEA (1.2 eq.)
and MsCl (1.1 eq.) were added and the mixture stirred at 0°C for 1 h. The mixture
was diluted with DCM and washed with water. The org. phase was dried over MgSO
4 and concentrated to give the desired mesylate as a colourless solid, which was used
in the next step without further purification.
Procedure E: Boc deprotection:
[0113] The Boc-protected amine (1 mmol) is dissolved in DCM (5 mL) and treated with TFA
(2 mL). The mixture is stirred at rt for 1 h, concentrated
in vacuo and taken up in DCM/NH
4OH. The org. layer is washed with water, dried over MgSO
4 and concentrated. The reaction optionally be performed in presence of Et
3SiH.
Procedure F: Silylether removal:
[0114] A solution of the silylether (4 mmol) in THF (10 mL) was treated with TBAF solution
(1M in THF, 1 eq.). The solution was stirred at 0°C for 2 h and at 1-12 h at rt until
completion of the reaction, after which water and EA were added. The aq. phase was
extracted with EA. The combined org. layers were washed with brine, dried over MgSO
4, filtered and concentrated under reduced pressure. The residue was crystallized from
ether/EA to afford the desired alcohol.
Procedure G: Oxazolidinones from glycidyl butyrates and Cbz-protected amines:
[0115] A solution of Cbz-protected amine (10 mmol, prepared according to procedure C) in
THF (60 mL) was cooled to -78°C before the dropwise addition of n-BuLi (2.5M solution
in hexanes, 1.2 eq.). The mixture was stirred at -78°C for 1 h and then warmed to
-15°C. At this temperature
(S or R)-glycidyl butyrate (1.2 eq.) was added dropwise. The mixture was stirred at rt overnight.
Cs
2CO
3 (tip of a spatula) was added and the mixture heated at 40°C until complete conversion.
The mixture was diluted with EA and washed with sat. NH
4Cl solution and water. The org. layer was dried over MgSO
4, concentrated under reduced pressure and purified by CC. Alternatively the reaction
can also be performed using 3 eq. of LiOtBu in DMF at rt.
Procedure H: Michael addition on acrylate
[0116] A solution of the quinolinone derivative (3.5 mmol) in MeCN (7 mL) was refluxed in
presence of the required acrylate derivative (1 eq.) and CsF (0.1 eq.). The reaction
mixture was diluted with EA (35 mL) and extracted with water (40 mL). The org layer
was backwashed with EA and the combined org. layers were dried over MgSO
4, evaporated under reduced pressure. The residue was used as such in the following
step.
Procedure I: Reductive amination
[0117] A solution of primary amine (1 mmol) and aldehyde or ketone (1 mmol) in DCE/MeOH
1:1 (10 mL) is stirred at rt overnight. NaBH
4 (2-5 eq.) is added and the reaction allowed to proceed for another hour. The reaction
is diluted with DCM and aq. NH
4OH. The org. phase is washed with water, dried over MgSO
4 and concentrated.
Procedure J: Formation of aldehyde from ester
[0118] A solution of the ester (1.46 mmol) in toluene (22 mL) was cooled to -78°C and treated
dropwise with DIBAH (2.6 mL, 4.38 mmol, 3 eq., solution ∼1.7
M in toluene). The mixture was further stirred at this temperature for 2 h and quenched
by the dropwise addition of Rochelles salt (sat. solution, 4 mL). The reaction mixture
was allowed to reach rt. The solution was diluted with EA (20 mL) and treated with
a sat. solution of Rochelles salt (15 mL). The org. phase was separated and the aq.
layer was extracted with EA. The combined org. layers were washed with sat. solution
of Rochelles salt (15 mL), dried over MgSO
4, filtered and concentrated under reduced. The crude product was purified by CC.
Procedure K: Ester hydrolysis
[0119] A solution of the ester (304 mg) was stirred at 50°C for 8h in a mixture of 4N HCl
in dioxane (7.5 mL; 2:1). The solution was diluted with EA (20 mL) and water (20 mL).
The two phases were separated, the aq. layer was washed with EA (20 mL). The combined
org. layers were washed with brine (20 mL) and dried over MgSO
4, filtered, concentrated under reduced pressure and used in the next step.
Procedure L: amide coupling using propylphosphonic anhydride:
[0120] A solution of DIPEA (0.124 mL, 0.75 mmol, 3 eq.), the acid (0.25 mmol, 1 eq.) and
the amine (70 mg, 0.25 mmol, 1 eq.) in DMF (2 mL) was treated dropwise with T3P (Propylphosphonic
anhydride solution ∼50% in EA, 0.162 mL, 0.275 mmol, 1.1 eq.). The reaction mixture
was stirred at rt for 6 h, diluted with EA (2 mL) and water (2 mL) and filtered. The
crude product was triturated in water, EA/MeOH (1:2) and filtered. The solid was sequentially
washed with DCM/ether (1:1) and ether, and dried under HV, affording the desired amide.
Procedure M: alkylation of an amine.
[0121] A solution of the amine (0.5 mmol), the mesylate or iodide (0.5 mmol) and DIPEA (1.2
eq.) in DMSO (3 mL) was heated at 70°C for 24 h. The mixture was partitioned between
EA and water. The org. layer was washed with water and brine, dried over MgSO
4 and concentrated under reduced pressure. The residue was purified by CC.
PREPARATION OF EXAMPLES
Preparation of intermediates:
Intermediate A: (R)-5-aminomethyl-3-(2,3-dihydro-benzo[1,4]dioxin-6-yl)-oxazolidin-2-one:
A.i. (S)-3-(2,3-dihydro-benzo[1,4]dioxin-6-yl)-5-hydroxymethyl-oxazolidin- 2-one:
[0122] The title compound was prepared from (2,3-dihydro-benzo[1,4]dioxin-6-yl)-carbamic
acid benzyl ester (3.0 g, 10.5 mmol) and (S)-glycidyl butyrate (1.98 g, 1.2 eq.) according
to procedure G. The yield was 1.09 g (41%; beige solid).
1H NMR (DMSO d6) δ: 7.13 (d, J = 2.5 Hz, 1H), 6.96 (dd, J = 2.5, 8.9 Hz, 1H), 6.86
(d, J = 8.9 Hz, 1H), 5.16 (t, J = 5.8 Hz, 1H), 4.70-4.50 (m, 1H), 4.30-4.10 (m, 4H),
4.10-3.90 (m, 1H), 4.80-4.70 (m, 1H), 4.70-4.60 (m, 1H), 4.60-4.50 (m, 1H).
A.ii. Methanesulfonic acid (S)-3-(2,3-dihydro-benzo[1,4]dioxin-6-y/)-2-oxo-oxazolidin-5-ylmethyl ester:
[0123] The compound was prepared from intermediate A.i (1 g, 4 mmol) according to procedure
D. The yield was 1.26 g (97%; colourless solid). The intermediate was used in the
next step without further purification.
MS (ESI, m/z): 329.8 [M+H
+].
A.iii. (S)-5-azidomethyl-3-(2,3-dihydro-benzo[1,4]dioxin-6-yl)-oxazolidin-2-one:
[0124] A solution of intermediate A.ii (1.26 g, 3.8 mmol) in DMF (20 mL) was treated with
NaN
3 (0.3 g, 1.2 eq.) and the mixture heated at 80°C overnight. The mixture was cooled
and partitioned between ether and water. The org. phase was washed with water and
brine, dried over MgSO
4 and concentrated to give the desired azide as a colourless solid (0.95 g, 90% yield).
MS (ESI, m/z): 277.1 [M+H
+].
A.iv. (R)-5-aminomethyl-3-(2,3-dihydro-benzo[1,4]dioxin-6-yl)-oxazolidin-2-one:
[0125] A solution of intermediate A.iii (0.95 g, 3.4 mmol) in EtOH/THF (1:1, 40 mL) was
hydrogenated over Pd(OH)
2 (0.18 g, 0.1 eq.) under 1 bar of H
2 for 3 h. The catalyst was filtered off and the filtrate concentrated
in vacuo to give the desired amine as a colourless solid (0.62 g, 72% yield).
1H NMR (DMSO d6) δ: 7.12 (d, J = 2.5 Hz, 1H), 6.98 (dd, J = 2.5, 8.9 Hz, 1H), 6.86
(d, J = 8.9 Hz, 1H), 4.60-4.50 (m, 1H), 4.30-4.10 (m, 4H), 3.99 (t, J = 8.8 Hz, 1H),
3.79 (dd, J = 6.5, 8.8 Hz, 1H), 3.90-3.75 (m, 2H).
MS (ESI, m/z): 251.0 [M+H
+].
Intermediate B: 6-((R)-5-aminomethyl-2-oxo-oxazolidin-3-yl)-4H-benzo[1,4]thiazin-3-one:
B.i. (R)-3-chloro-2-hydroxy-propyl)-carbamic acid tert-butyl ester:
[0126] This intermediate (25.6 g, 45% yield) was prepared according to the literature (
Org. Process Research and Development (2003), 7, 533-546) starting from (R)-epichlorohydrin (25 g, 270 mmol).
1H NMR (CDCl
3) δ: 4.95 (br, 1H), 4.00-3.80 (m, 1H), 3.60-3.50 (m, 2H), 3.50-3.35 (m, 2H), 3.30-3.20
(m, 1H), 1.42 (s, 9H).
B.ii. (R)-1-oxiranylmethyl-carbamic acid tert-butyl ester:
[0127] NaOMe (1.9 g, 34.9 mmol) was added to a solution of intermediate B.i (3.66 g, 17.4
mmol) in MeOH. The mixture was stirred at rt for 6 h, concentrated
in vacuo and partitioned between water and ether. The org. layer was washed with sat. NH
4Cl solution, dried over MgSO
4 and concentrated to give the title epoxide as a colourless oil (1.38 g, 45% yield).
1H NMR (DMSO d6) δ:4.71 (br, 1 H), 3.52 (m, 1 H), 3.21 (m, 1 H), 3.08 (m, 1 H), 2.77
(m, 1 H), 1.42 (s, 9H).
B.iii. [(S)-2-hydroxy-3-(3-oxo-3,4-dihydro-2H-benzo[1,4]thiazin-6ylamino)propyl]-carbamic
acid tert-butyl ester:
[0128] This amino alcohol is synthesized according to procedure A starting from intermediate
B.ii (0.78 g, 4.5 mmol) and 6-amino-4
H-benzo[1,4]thiazin-3-one (0.68 g, 4.5 mmol). The compound was isolated after CC (hex/EA
2:1, 1:1, 1:2) as a beige foam (1.08 g, 68% yield).
MS (ESI, m/z): 354.2 [M+H
+].
B.iv. [(R)-2-oxo-3-(3-oxo-3,4-dihydro-2H-benzo[1,4]thiazin-6yl)-oxazolidin-5-ylmethyl]-carbamic
acid tert-butyl ester:
[0129] The compound was obtained from B.iii (1.5 g, 4.2 mmol) and CDI (0.78 g, 1.1 eq.)
according to procedure B (in order to push the reaction to completion NaH (1 eq.)
was added an stirring was continued at rt overnight). The compound was purified by
CC (hex/EA 1:2) giving the title oxazolidinone (0.61 g, 38% yield) as a pink foam.
1H NMR (DMSO d6) δ: 10.56 (s, 1 H), 7.30 (m, 2 H), 7.18 (m, 1 H), 7.08 (dd, J = 8.5,
2.3 Hz, 1 H), 4.66 (m, 1 H), 4.02 (m, 1 H), 3.73 (dd, J = 8.8, 6.2 Hz, 1 H), 3.40
(s, 2H), 3.30-3.20 (m, 2H), 1.34 (s, 9 H).
B.v. 6-((R)-5-aminomethyl-2-oxo-oxazolidin-3-yl)-4H-benzo[1,4]thiazin-3-one:
[0130] The Boc group of intermediate B.iv (0.6 g, 1.58 mmol) was removed according to procedure
E. The title amine was isolated as a beige foam (0.37 g, 85% yield).
MS (ESI, m/z): 280.2 [M+H
+].
Intermediate C: methanesulfonic acid (S)-2-oxo-3-(3-oxo-3,4-dihydro-2H-benzo[1,4]oxazin-6-yl)-oxazolidin-5-ylmethyl ester:
C.i 6-[(S)-3-(tert-butyl-dimethyl-silanyloxy)-2-hydroxy-propylamino]-4H-benzo[1,4]oxazin-3-one:
[0131] To a solution of
tert-butyl-dimethyl-((
S)-1-oxiranylmethoxy)-silane (commercial; 10.0 g, 53 mmol) in MeCN (160 mL) was added
LiClO
4 (16.9 g, 159 mmol). 6-amino-4H-benzo[1,4]oxazin-3-one (commercial; 8.72 g, 53.1 mmol)
was added and the mixture was stirred at 50°C for 6 h. The solvent was removed
in vacuo and the residue was purified by CC (DCM/MeOH/NH
4OH 1000:25:2 ->1000:100:2) to afford the title compound as a pale brown foam (10.24
g, 55% yield).
MS (ESI, m/z): 353.3 [M+H
+].
C.ii. 6-[(S)-5-(tert-butyl-dimethyl-silanyloxymethyl)-2-oxo-oxazolidin-3-yl]-4H-benzo[1,4]oxazin-3-one:
[0132] A solution of intermediate C.i (10.24 g, 29 mmol) and CDI (9.71 g, 58.1 mmol) in
THF (140 mL) was heated at 50°C for 2 h; the mixture was concentrated
in vacuo and partitioned between EA and water. The org. layer was washed with brine, dried
over MgSO
4 and concentrated under reduced pressure. The residue was triturated with ether to
afford the title intermediate as a yellowish solid (6.30 g, 57% yield).
MS (ESI, m/z): 379.2 [M+H
+].
C.iii. 6-((S)-5-hydroxymethyl-2-oxo-oxazolidin-3-yl)-4H-benzo[1,4]oxazin-3-one:
[0133] A suspension of intermediate C.ii (6.30 g, 16.6 mmol) in THF (20 mL) was treated
with TBAF (1M in THF, 16.6 mL) at 0°C. The yellow solution was stirred at 0°C for
3 h and then partitioned between water and EA. The aq. phase was extracted with EA
(3x). The combined org. layers were washed with brine, dried over MgSO
4, filtered and concentrated under reduced pressure. The crude product was triturated
with EA to give the title intermediate as a colourless solid (3.49 g, 79% yield).
MS (ESI, m/z): 265.5 [M+H
+].
C.iv. Methanesulfonic acid (S)-2-oxo-3-(3-oxo-3,4-dihydro-2H-benzo[1,4]oxazin-6-y/)-oxazolidin-5-ylmethyl ester:
[0134] A solution of intermediate C.iii (2.44 g, 9.23 mmol) in DCM (50 mL) was cooled to
0°C. DIPEA (3.58 g, 3 eq.) and Ms-Cl (1.27 g, 1.2 eq.) were added and the mixture
stirred at 0°C for 1 h. The mixture was diluted with DCM and washed with water. The
org. phase was dried over MgSO
4 and concentrated. The residue was purified by CC (DCM/MeOH 1000:50:4) to afford the
title compound as an off-white solid (1.40 g, 44% yield).
1H NMR (DMSO-d6) δ: 10.72 (s, 1H), 7.29 (dd, J = 2.1, 0.6 Hz, 1H), 6.94 (m, 2H), 4.95
(m, 1H), 4.52 (s, 2H), 4.49 (m, 2H), 4.11 (t, J = 9.1 Hz, 1H), 3.73 (m, 2H), 3.23
(s, 3H).
MS (ESI, m/z): 343.2 [M+H
+].
Intermediate D: (RS)-methanesulfonic acid 2-[2-oxo-3-(3-oxo-3,4-dihydro-2H-benzo[1,4]thiazin-6-yl)-oxazolidin-5-yl]-ethyl
ester:
D.i. (RS)-6-[4-(tert-butyl-dimethyl-silanyloxy)-2-hydroxy-butylamino]-4H-benzo[1,4]thiazin-3-one:
[0135] The compound was obtained according to procedure A starting from (RS)-tert-butyldimethyl-(2-oxiranyl-ethoxy)-silane
(4 g, 20 mmol, prepared according to
Heterocycles (1987), 25(1), 329-32) and 6-amino-4H-benzo[1,4]thiazin-3-one (4 g, 20 mmol) in EtOH/water 9:1 (140 mL).
The compound was purified by CC (DCM/MeOH/NH
4OH 1000:50:4), affording a brown oil (2.2 g, 29% yield).
MS (ESI, m/z): 383.2 [M+H
+].
D.ii. (RS)-6-{5-[2-(tert-butyl-dimethyl-silanyloxy)-ethyl]-2-oxo-oxazolidin-3-yl}-4H-benzo[1,4]thiazin-3-one:
[0136] According to procedure B the title intermediate was obtained from intermediate D.i
and isolated as an orange solid (1.53 g, 65% yield) after CC (DCM/MeOH/NH
4OH 1000:50:4). MS (ESI, m/z): 409.4 [M+H
+].
D.iii. (RS)-6-[5-(2-hydroxy-ethyl)-2-oxo-oxazolidin-3-yl]-4H-benzo[1,4]thiazin-3-one:
[0137] The compound was prepared according to procedure F starting from intermediate D.ii
(1.50 g, 3.67 mmol). The residue was recrystallized from ether/EA to afford the title
intermediate as a beige solid (730 mg, 68% yield).
MS (ESI, m/z): 295.1 [M+H
+].
D.iv. (RS)-methanesulfonic acid 2-[2-oxo-3-(3-oxo-3,4-dihydro-2H-benzo[1,4]thiazin-6-yl)-oxazolidin-5-yl]-ethyl
ester:
[0138] The compound was obtained according to procedure D starting from intermediate D.iii
(700 mg, 2.34 mmol). The yellow residue was purified by CC (DCM/MeOH/NH
4OH 1000:50:4), affording the title intermediate as a beige solid (795 mg, 90% yield).
MS (ESI, m/z): 373.1 [M+H
+].
Intermediate E: 6-((S)-5-iodomethyl-2-oxo-oxazolidin-3-yl)-4H-benzo[1,4]thiazin-3-one:
E.i. 6-[(S)-3-(tert-butyl-dimethyl-silanyloxy)-2-hydroxy-propylamino]-4H-benzo[1,4]thiazin-3-one:
[0139] To a solution of
tert-butyl-dimethyl-((
S)-1-oxiranylmethoxy)-silane (commercial; 13.0 g, 69 mmol) in MeCN (220 mL) was added
LiClO
4 (22 g, 207 mmol). 6-amino-4H-benzo[1,4]thiazin-3-one (commercial; 11.45 g, 64 mmol)
was added and the mixture was stirred at 50°C for 6 h. The solvent was removed
in vacuo and the residue was purified by CC (DCM/MeOH/NH
4OH 1000:25:2 -> 1000:100:2) to afford the title compound as a pale brown foam (11.16
g, 44% yield).
MS (ESI, m/z): 353.3 [M+H
+].
E.ii. 6-[(S)-5-(tert-buyl-dimethyl-silanyloxymethyl)-2-oxo-oxazolidin-3-yl]-4H-benzo[1,4]thiazin-3-one:
[0140] A solution of intermediate E.i (11.16 g, 30 mmol) and CDI (5.57 g, 33 mmol) in THF
(130 mL) was heated at 50°C for 2 h; the mixture was concentrated
in vacuo and partitioned between EA and water. Some crystallized product was filtered and
washed with H
2O and EA to give 5.21 g of solid. The org. layer was washed with brine, dried over
MgSO
4 and concentrated under reduced pressure. The residue was purified by CC (DCM/MeOH
1000:50:4) to give additional 2.28 g as a colourless solid (total 7.49 g, 63% yield).
MS (ESI, m/z): 379.2 [M+H
+].
E.iii. 6-((S)-5-hydrozymethyl-2-oxo-oxazolidin-3-yl)-4H-benzo[1,4]thiazin-3-one:
[0141] A suspension of intermediate E.ii (11.49 g, 29.1 mmol) in THF (30 mL) was treated
with TBAF (1
M in THF, 29.1 mL) at 0°C. The yellow solution was stirred at 0°C for 3 h and then
partitioned between water and EA. Some crystallized product was filtered and washed
with H
2O and EA to give 6.49 g of solid. The aq. phase was extracted with EA (3x). The combined
org. layers were washed with brine, dried over MgSO
4, filtered and concentrated under reduced pressure. The crude product was triturated
with EA to give 1.23 g (overall 7.72 g of an off-white solid, 95% yield).
MS (ESI, m/z): 265.5 [M+H
+].
E.iv. Toluene-4-sulfonic acid (S)-2-oxo-3-(3-oxo-3,4-dihydro-2H-benzo[1,4]thiazin-6-yl)-oxazolidin-5-ylmethyl
ester:
[0142] To a solution of intermediate E.iii (3.22 g, 11.5 mmol) and DMAP (1.40 g, 11.5 mmol)
in DCM (80 mL) cooled to 0 °C were added TEA (4.6 mL, 33.3 mmol) and a solution of
TsCl (2.19 g, 11.5 mmol) in DCM (15 mL). The mixture was stirred at rt overnight after
which water was added. The resulting solid was filtered and dried to afford the title
compound as a beige solid (4.19 g, 84% yield).
MS (ESI, m/z): 435.2 [M+H
+].
E.v. 6-((S)-5-iodomethyl-2-oxo-oxazolidin-3-yl)-4H-benzo[1,4]thiazin-3-one:
[0143] A suspension of intermediate E.iv (4.19 g, 9.64 mmol) and NaI (5.78 g, 38.57 mmol)
in acetone (70 mL) was refluxed for 5 h. The solvent was evaporated and the residue
extracted with water/DCM. Thereby the desired product precipitated as a pale beige
solid (3.40 g; 90% yield)
MS (ESI, m/z): 391.1 [M+H
+].
Intermediate F: 7-fluoro-6-((S)-5-iodomethyl-2-oxo-oxazolidin-3-yl)-4H-benzo[1,4]thiazin-3-one:
F.i. 6-amino-7-fluoro-4H-benzo[1,4]thiazin-3-one:
[0144] Starting from 1,5-difluoro-2,4-dinitro-benzene (5 g) and following the procedure
described in the literature (
Biosci. Biotechnol., Biochem. 1994, 58, 788), the title aniline was isolated as a beige solid (2 g, 55% yield).
1H NMR (DMSO-d6) δ: 10.28 (s, 1 H), 6.94 (d, J = 10.8 Hz, 1H), 6.40 (d, J = 8.5 Hz,
1H), 5.22 (s, 2H), 3.31 (s, 2H).
F.ii. 7-fluoro-6-((S)-5-chloromethyl-2-oxo-oxazolidin-3-yl)-4H-benzo[1,4]thiazin-3-one:
[0145] Starting from intermediate F.i (1 g, 5.05 mmol) and (S)-epichlorohydrin (0.4 ml)
and following procedures A and B, the title intermediate was isolated as a brown solid
(380 mg, 30% yield).
MS (ESI, m/z): 317.1 [M+H
+].
F.iii 7-fluoro-6-((S)-5-iodomethyl-2-oxo-oxazolidin-3-yl)-4H-benzo[1,4]thiazin-3-one:
[0146] A sat. solution of intermediate F.ii (0.38 g, 1.5 mmol) in 2-butanone at reflux (3
mL) was treated with NaI and heated at reflux (80°C) over 2 nights. The mixture was
cooled to rt and concentrated under reduced pressure and digested with water, vigorously
stirred for 5 min and filtered. The precipitated product was purified by CC (Hept/EA
1:1, EA/MeOH 9:1) to give 390 mg (80% yield) of a beige solid.
MS (ESI, m/z): 409.1 [M+H
+].
Intermediate G: (S)-3-(2,3-dihydro-benzo[1,4]dioxin-6-yl)-5-iodomethyl-oxazolidin-2-one:
G.i. (S)-3-(2,3-dihydro-benzo[1,4]dioxin-6-yl)-5-hydroxymethyl-oxazolidin-2-one:
[0147] A solution of (2,3-dihydro-benzo[1,4]dioxin-6-yl)-carbamic acid benzyl ester (13.0
g, 45.6 mmol) in THF (220 mL) was cooled to -78°C before the drop wise addition of
n-BuLi (29.5 mL of a 2.36M solution in Hex, 1.1 eq.). The mixture was stirred at -78°C
for 1 h and then warmed to -15°C. At this temperature (S)-glycidyl butyrate (7.37
g, 1.1 eq.) was added dropwise. The mixture was stirred at rt overnight. Cs
2CO
3 (tip of a spatula) was added and the mixture heated at 40°C until complete conversion.
The mixture was diluted with EA and washed with a sat. aq. NH
4Cl and water. The org. layer was dried over MgSO
4 and concentrated. The residue was purified by CC (Hex/EA 2:1, 1:1) to afford the
title intermediate as a grey solid (7.04 g, 62% yield).
1H NMR (DMSO-d6) δ: 7.13 (d, J = 2.5 Hz, 1H), 6.96 (dd, J = 2.5, 8.9 Hz, 1H), 6.86
(d, J = 8.9 Hz, 1H), 5.16 (t, J=5.8Hz, 1H), 4.70-4.50 (m, 1H), 4.30-4.10 (m, 4H),
4.10-3.90 (m, 1H), 4.80-4.70 (m, 1H), 4.70-4.60 (m, 1H), 4.60-4.50 (m, 1H).
G.ii. Methanesulfonic acid (S)-3-(2,3-dihydro-benzo[1,4]dioxin-6-yl)-2-oxo-oxazolidin-5-ylmethyl
ester:
[0148] A solution of intermediate G.i (7.0 g, 27.9 mmol) in DCM (140 mL) was cooled to 0°C.
DIPEA (5.70 mL, 1.2 eq) and MsCl (2.40 mL, 1.1 eq) were added and the mixture was
stirred for 1 h at 0°C. The mixture was diluted with DCM and washed with water. The
org. phase was dried over MgSO
4 and concentrated to give the title intermediate as a colourless solid (9.0 g, 98%
yield).
MS (ESI, m/z): 330.3 [M+H
+].
G.iii. (S)-3-(2,3-Dihydro-benzo[1,4]dioxin-6-yl)-5-iodomethyl-oxazolidin-2-one:
[0149] A mixture of intermediate G.ii (9.0 g, 27.3 mmol) and NaI (16.4 g, 4 eq.) in acetone
(150 mL) was heated at reflux for 20 h. The solvent was evaporated and the residue
extracted with water/DCM. The org. layer was washed with brine, dried over MgSO
4 and concentrated under reduced pressure. The residue was triturated with ether/EA
to afford the title intermediate as an off-white solid (6.91 g, 70% yield).
1H NMR (CDCl
3) δ: 7.07 (d, J = 2.6 Hz, 1 H), 6.98 (dd, J = 9.1, 2.6 Hz, 1 H), 6.85 (d, J = 8.9
Hz, 1 H), 4.68 (m, 1 H), 4.24 (s, 4 H), 4.10 (t, J = 9.1 Hz, 1 H), 3.72 (dd, J = 9.1,
5.9 Hz, 1 H), 3.46 (m, 1 H), 3.33 (m, 1 H).
MS (ESI, m/z): 362.2 [M+H
+].
Intermediate H: methanesulfonic acid 2-[(R)-2-oxo-3-(3-oxo-3,4-dihydro-2H-benzo[1,4]thiazin-6-yl)-oxazolidin-5-yl]-ethyl ester
H.i. Tert-butyl-dimethyl-((R)-2-oxiranyl-ethoxy)-silane and (2S)-4-(tert-butyl-dimethyl-silanyloxy)-butane-1,2-diol:
[0150] The title intermediates were prepared in analogy to
Kishi et al. Org. Lett. 2005, 7, 3997 (intermediate S2-3), via hydrolytic kinetic resolution of (RS)-tert-butyl-dimethyl-(2-oxiranyl-ethoxy)-silane
(prepared according to
J. Org. Chem. 2008, 73, 1093). Two compounds were isolated after CC (Hept/EA 2:1):
First eluting compound: tert-butyl-dimethyl-((R)-2-oxiranyl-ethoxy)-silane (colourless
oil, 25.3 g, 48% yield). 1H NMR (CDCl3) δ: 3.77 (t, J = 6.4 Hz, 2H), 3.04 (m, 1H), 2.78 (m, 1H), 2.51 (dd, J = 5.0, 2.9
Hz, 1H), 1.74 (m, 2H), 0.90 (d, J = 0.6 Hz, 9H), 0.06 (s, 6H).
Second eluting compound: (2S)-4-(tert-butyl-dimethyl-silanyloxy)-butane-1,2-diol (colourless
oil, 24.9 g, 43% yield). 1H NMR (CDCl3) δ: 3.89 (m, 3H), 3.62 (s, 1H), 3.53 (m, 1H), 3.42 (br. s, 1H), 2.29 (m, 1H), 1.70
(m, 2H), 0.90 (s, 9H), 0.09 (s, 6H).
H.ii. 6-[(R)-4-(tert-butyl-dimethyl-silanyloxy)-2-hydroxy-butylamino]-4H-benzo[1,4]thiazin-3-one:
[0151] A solution of 6-amino-4H-benzo[1,4]thiazin-3-one (10.68 g, 59.3 mmol; commercial)
and tert-butyl-dimethyl-((R)-2-oxiranyl-ethoxy)-silane (as described in H.i, 12.0
g, 59.3 mmol) in 9-1 EtOH/H
2O (320 mL) was heated at 80°C for 2 days. The mixture was concentrated under reduced
pressure. Residual starting aniline could be removed by addition of ether/MeOH followed
by filtration. The mother liquor containing the product was concentrated under reduced
pressure to afford the title intermediate as a brown oil (18.8 g, 83% yield) which
was used as such in the next step.
MS (ESI, m/z): 383.2 [M+H
+].
H.iii. 6-{(R)-5-[2-(tert-butyl-dimethyl-silanyloxy)-ethyl]-2-oxo-oxazolidin-3-yl}-4H-benzo[1,4]thiazin-3-one:
[0152] A solution of intermediate H.ii (23.5 g, 49.1 mmol) and CDI (9.57 g, 1.2 eq.) in
THF (250 mL) was heated at 50°C overnight. The mixture was concentrated under reduced
pressure and partitioned between EA and water. The aq. layer was extracted once more
with EA and the combined org. layers were dried over MgSO
4 and concentrated. The residue was purified by CC (DCM/MeOH/NH
4OH 1000:50:4) to afford the title intermediate as a colourless solid (8.4 g, 42% yield).
MS (ESI, m/z): 409.3 [M+H
+].
H.iv. 6-[(R)-S-(2-hydroxy-ethyl)-2-oxo-oxazolidin-3-yl]-4H-benzo[1,4]thiazin-3-one:
[0153] A solution of intermediate H.iii (8.4 g, 20.6 mmol) in THF (50 mL) was treated with
TBAF (1M solution in THF, 24.7 mL, 1.2 eq.) at 0°C. The solution was stirred at 0°C
for 6 h. The mixture was partitioned between water and EA and the aq. phase was extracted
with EA (3x). The combined org. layers were washed with water and brine, dried over
MgSO
4 and concentrated. The residue was triturated with ether/EA to afford the title intermediate
as an off-white solid (4.79 g, 79% yield).
MS (ESI, m/z): 295.5 [M+H
+].
H.v. Methanesulfonic acid 2-[(R)-2-oxo-3-(3-oxo-3,4-dihydro-2H-benzo[1,4]thiazin-6-yl)-oxazolidin-5-yl]-ethyl
ester:
[0154] A solution of intermediate H.iv (4.7 g, 16.0 mmol) and DIPEA (7.54 mL, 2.9 eq.) in
anhydrous DCM (80 mL) was cooled to 0°C and treated dropwise with MsCl (1.50 mL, 1.2
eq.). The resulting mixture was stirred at 0°C for 1 h. Water and DCM were added and
the phases separated. The org. layer was dried over MgSO
4 and concentrated under reduced pressure. The residue was purified by CC (DCM/MeOH/NH
4OH 1000:50:4) to afford the title intermediate as an off-white solid (5.80 g, 98%
yield).
MS (ESI, m/z): 373.4 [M+H
+].
Intermediate I: methanesulfonic acid 2-[(S)-2-oxo-3-(3-oxo-3,4-dihydro-2H-benzo[1,4]oxazin-6-yl)-oxazolidin-5-yl]-ethyl ester:
I.i. Toluene-4-sulfonic acid (S)-4-(tert-butyl-dimethyl-silanyloxy)-2-hydroxy-butyl
ester:
[0155] To a solution of (2S)-4-(tert-butyl-dimethyl-silanyloxy)-butane-1,2-diol (23.9 g,
108 mmol, second eluting compound of H.i) and DMAP (2.65 g, 0.2 eq.) in DCM (80 mL)
cooled to 0°C were added TEA (43.8 mL, 2.9 eq.) and a solution of p-TsCl (20.7 g,
1 1q) in DCM (15 mL). The mixture was stirred at rt for 5 h, poured on NaHCO
3 and extracted with DCM. The org. layer was dried over MgSO
4 and concentrated. The residue was purified by CC (Hept/EA 2:1) to afford the title
intermediate as a colourless oil (31.3 g, 77% yield).
1H NMR (CDCl
3) δ: 7.80 (d, J = 7.6 Hz, 2H), 7.34 (d, J = 7.6 Hz, 2H), 4.02 (m, 3H), 3.80 (m, 2H),
2.45 (s, 3H), 1.70 (m, 2H), 1.27 (m, 1H), 0.87 (s, 9H), 0.05 (s, 6H).
I.ii. Tert-butyl-dimethyl-((S)-2-oxiranyl-ethoxy)-silane:
[0156] To a solution of intermediate I.i (31.1 g, 83.1 mmol) in THF (350 mL) was added 2M
NaOH (35 mL) and the mixture was vigorously stirred at rt for 3 h. The mixture was
taken in 1M NaOH (200 mL) and extracted with TBME (2x). The combined org. layers were
washed with water and brine, dried over MgSO
4 and concentrated. The resulting oil was purified by Kugelrohr-distillation (ca. 70°C
at 0.1 mbar) to afford the title intermediate as a colourless oil (14.7 g, 87% yield).
1H NMR (CDCl
3) δ: 3.77 (t, J = 6.4 Hz, 2H), 3.04 (m, 1H), 2.78 (m, 1H), 2.51 (dd, J = 5.0, 2.9
Hz, 1H), 1.74 (m, 2H), 0.90 (d, J = 0.6 Hz, 9H), 0.06 (s, 6H).
I.iii. 6-[(S)-4-(tert-butyl-dimethyl-silanyloxy)-2-hydroxy-butylamino]-4H-benzo[1,4]oxazin-3-one:
[0157] A solution of 6-amino4H-benzo[1,4]oxazin-3-one (5.03 g, 30.6 mmol; commercial) and
intermediate I.ii (6.2 g, 1 eq.) in 9-1 EtOH/H
2O (180 mL) was heated at 80°C for 2 days. The mixture was concentrated under reduced
pressure. Residual starting aniline could be removed by addition of ether/MeOH followed
by filtration. The mother liquor containing the product was concentrated under reduced
pressure to afford the title intermediate as a brown oil (9.45 g, 84% yield) which
was used as such in the next step.
MS (ESI, m/z): 367.2 [M+H
+].
I.iv. 6-{(S)-5-[2-(tert-butyl-dimethyl-silanyloxy)-ethyl]-2-oxo-oxazolidin-3-yl}-4H-benzo[1,4]oxazin-3-one:
[0158] A solution of intermediate I.iii (9.4 g, 25.6 mmol) and CDI (4.99 g, 1.2 eq.) in
THF (100 mL) was heated at 50°C overnight. The mixture was concentrated under reduced
pressure and partitioned between EA and water. The aq. layer was extracted once more
with EA and the combined org. layers were washed with 0.5M HCl (2x) and water, dried
over MgSO
4 and concentrated. The residue was triturated, the solids filtered off and the mother
liquor was concentrated. The resulting solid was triturated once more, the solids
filtered off and the mother liquor was concentrated. The residue was purified by CC
(DCM/MeOH/NH
4OH 1000:50:4) to afford the title intermediate as a beige solid (2.40 g, 24% yield).
MS (ESI, m/z): 393.4 [M+H
+].
I.v. 6-[(S)-5-(2-hydroxy-ethyl)-2-oxo-oxazolidin-3-yl]-4H-benzo[1,4]oxazin-3-one:
[0159] A solution of intermediate I.iv (2.40 g, 6.11 mmol) in THF (12 mL) was treated with
TBAF (1M solution in THF, 7.33 mL, 1.2 eq.) at 0°C. The solution was stirred at 0°C
for 6 h. The mixture was partitioned between water and EA and the aq. phase was extracted
with EA (3x). The combined org. layers were washed with water (3x) and brine, dried
over MgSO
4 and concentrated. The residue was triturated with ether/EA to afford the title intermediate
as an off-white solid (0.82 g, 48% yield).
MS (ESI, m/z): 279.5 [M+H
+].
I.vi. Methanesulfonic acid 2-[(S)-2-oxo-3-(3-oxo-3,4-dihydro-2H-benzo[1,4]oxazin-6-yl)-oxazolidin-5-yl]-ethyl
ester:
[0160] A solution of intermediate I.v (0.82 g, 2.95 mmol) and DIPEA (1.4 mL, 2.9 eq.) in
anhydrous DCM (15 mL) was cooled to 0°C and treated dropwise with MsCl (0.28 mL, 1.2
eq.). The resulting mixture was stirred at 0°C for 1 h. Water and DCM were added and
the phases separated. The org. layer was dried over MgSO
4 and concentrated under reduced pressure. The residue was triturated with MeOH to
afford the title intermediate as a beige solid (0.61 g, 58% yield).
MS (ESI, m/z): 357.3 [M+H
+].
Intermediate J: 6-[(R)-5-(2-iodo-ethyl)-2-oxo-oxazolidin-3-yl]-4H-benzo[1,4]thiazin-3-one:
[0161] A suspension of intermediate H.v (3.5 g, 9.4 mmol) and NaI (4.23 g, 3 eq.) in 2-butanone
(35 mL) was heated at 85°C overnight. After cooling, the mixture was diluted with
ether/EA (20 mL) and treated with 10% aq. Na
2S
2O
3 (60 mL). After stirring for 10 min the phases were separated and the aq. layer was
washed with EA. The combined org. layers were washed with water (2x), dried over MgSO
4 and concentrated under reduced pressure. The residue was triturated with ether/EA
to afford the title intermediate as an off-white solid (3.52 g, 93% yield).
MS (ESI, m/z): 405.0 [M+H
+].
Intermediate K: methanesulfonic acid 3-[(R)-2-oxo-3-(3-oxo-3,4-dihydro-2H-benzo[1,4]thiazin-6-yl)-oxazolidin-5-yl]-propyl ester
K.i. 6-[(R)-5-(tert-butyl-dimethyl-silanyloxy)-2-hydroxy-pentylamino]-4H-benzo[1,4]thiazin-3-one:
[0162] A mixture of tert-butyl-dimethyl-((R)-3-oxiranyl-propoxy)-silane (13 g, 60 mmol,
prepared according to
Org. Lett. 2005, 7, 3997) and 6-amino-4H-benzo[1,4]thiazin-3-one (10.8 g) in EtOH/H
2O (9:1, 325 mL) was heated at reflux overnight. The volatiles were removed under reduced
pressure and the residue purified by CC (Hept/EA 1:1) to give the desired intermediate
(6.8 g, 28% yield) as a brown oil.
MS (ESI, m/z): 397.1 [M+H
+].
K.ii. 6-{(R)-5-[3-(tert-butyl-dimethyl-silanyloxy)-propyl]-2-oxo-oxazolidin-3-yl}-4H-benzo[1,4]thiazin-3-one:
[0163] Starting with intermediate K.i (6.7 g, 17 mmol) and using procedure B, the title
intermediate was obtained as a orange solid (7.8 g, quant.).
MS (ESI, m/z): 423.4 [M+H
+].
K.iii. 6-[(R)-5-(3-hydroxy-propyl)-2-oxo-oxazolidin-3-yl]-4H-benzo[1,4]thiazin-3-one:
[0164] Starting with intermediate K.ii (7.1 g, 16.8 mmol) and using procedure F, the title
intermediate was obtained as a yellowish solid (3.1g, 60% yield).
MS (ESI, m/z): 309.1 [M+H
+].
K.iv. Methanesulfonic acid 3-[(R)-2-oxo-3-(3-oxo-3,4-dihydro-2H-benzo[1,4]thiazin-6-yl)-oxazolidin-5-yl]-propyl
ester:
[0165] Starting with intermediate K.iii (0.42 g, 1.36 mmol) and using procedure D, the title
intermediate was obtained as a beige solid (0.4g, 76% yield).
MS (ESI, m/z): 387.2 [M+H
+].
Intermediate L: methanesulfonic acid 2-[(S)-2-oxo-3-(3-oxo-3,4-dihydro-2H-benzo[1,4]thiazin-6-yl)-oxazolidin-5-yl]-ethyl ester:
L. i. 6-[(S)-4-(tert-butyl-dimethyl-silanyloxy)-2-hydroxy-butylamino]-4H-benzo[1,4]oxazin-3-one:
[0166] A suspension of 6-amino-4H-benzo[1,4]thiazin-3-one (24.5 g, 136 mmol; commercial),
intermediate I.ii (6.2 g, 1 eq) and LiClO
4 (43.4 g, 3 eq) in acetonitrile (400 mL) was heated at 60°C for 4h. The mixture was
concentrated under reduced pressure. The mixture was partitioned between EA and water.
The org. phase was washed with water and brine, dried over MgSO
4 and concentrated. The residue was purified by CC (Hept/EA 2:1, 1:1) to give the desired
intermediate as a yellow solid (20.6g, 40% yield) which was used as such in the next
step.
MS (ESI, m/z): 383.2 [M+H
+].
L.ii. 6-{(S)-5-[2-(tert-butyl-dimethyl-silanyloxy)-ethyl]-2-oxo-oxazolidin-3-yl}-4H-benzo[1,4]thiazin-3-one:
[0167] Starting with intermediate L.i (20.0 g, 52.2 mmol) and using procedure B, the title
intermediate was obtained as a beige solid (18.2 g, 85% yield).
1H NMR (CDCl
3) δ: 8.39 (s, 1 H), 7.40 (d, J = 2.3 Hz, 1H), 7.28 (m, 1H), 6.95 (dd, . J = 8.5, 2.3
Hz, 1H), 4.83 (m, 1H), 4.08 (t, J = 8.8 Hz, 1H), 3.79 (m, 4H), 3.41 (s, 2H), 2.01
(m, 2H), 0.90 (m, 9H), 0.07 (d, J = 2.9 Hz, 6H).
L.iii. 6-[(S)-5-(2-hydroxy-ethyl)-2-oxo-oxazolidin-3-yl]-4H-benzo[1,4]thiazin-3-one:
[0168] Starting with intermediate L.ii (18.0 g, 44 mmol) and using procedure F, the title
intermediate was obtained as an off-white solid (7.6 g, 60% yield).
MS (ESI, m/z): 295.5 [M+H
+].
L.iv. Methanesulfonic acid 2-[(S)-2-oxo-3-(3-oxo-3,4-dihydro-2H-benzo[1,4]thiazin-6-yl)-oxazolidin-5-yl]-ethyl
ester:
[0169] Starting with intermediate L.iii (3.0 g, 10.2 mmol) and using procedure D, the title
intermediate was obtained as a beige solid (3.6 g, 96% yield).
1H NMR (DMSO-d6) δ: 10.56 (s, 1H), 7.31 (m, 2H), 7.07 (dd, J = 8.8, 2.3 Hz, 1H), 4.78
(dd, J = 8.2, 6.7 Hz, 1H), 4.34 (td, J = 6.2, 2.9 Hz, 2H), 4.12 (t, J = 8.5 Hz, 1H),
3.73 (dd, J = 8.8, 7.0 Hz, 1H), 3.42 (s, 2H), 3.28 (s, 3H), 2.17 (q, J = 6.4 Hz, 2H).
MS (ESI, m/z): 373.3 [M+H
+].
Intermediate M: rac-methanesulfonic acid 2-[3-(2,3-dihydro-[1,4]dioxino[2,3-c]pyridin-7-yl)-2-oxo-oxazolidin-5-yl]-ethyl
ester:
M.i. (2,3-dihydro-[1,4]dioxino[2,3-c]pyridin-7-yl)-carbamic acid tert-butyl ester:
[0170] A suspension of 2,3-dihydro-1,4-dioxino[2,3-c]pyridine-7-carboxylic acid (3.2 g;
prepared according to
WO 03/042210), TEA (3 mL) and DPPA (4.6 mL) in t-BuOH was stirred at 80°C overnight. The solvent
was evaporated under reduced pressure and the residue was partitonated between EA
and water. The org. phase was washed with brine, dried over MgSO
4 and evaporated under reduced pressure. The residue was crystallized from ether, affording
a beige solid (2.9 g; 65% yield).
1H NMR (CDCl
3) δ: 7.95 (s, 1H), 7.84 (s, 1H), 7.49 (s, 1H), 4.31 (m, 2H), 4.23 (m, 2H), 1.52 (s,
9H).
M.ii. rac-5-[2-(tert-butyl-dimethyl-silanyloxy)-ethyl]-3-(2,3-dihydro-[1,4]dioxino[2,3-c]pyridin-7-yl)-oxazolidin-2-one:
[0171] A solution of intermediate M.i (3.3 g) and 2-[2-[[(tert-butyl)dimethylsilyl]oxy]ethyl]-oxirane
(2.65 g; prepared according to
WO 2007/144423) in DMF (40 mL) was cooled to 0°C and treated with a solution of lithium tert-butoxide
(2.2M in THF, 17.8 mL). The reaction mixture was allowed to reach rt and further stirred
at 80°C for 2 days. The reaction mixture was partitioned between EA and water. The
org. phase was washed with brine, dried over MgSO
4 and concentrated under reduced pressure. The residue was purified by CC (Hex-EA 2:1
to 1:1), affording a yellow oil (2.7 g, 54% yield).
MS (ESI, m/z): 381.0 [M+H
+].
M.iii. rac-3-(2,3-dihydro-[1,4]dioxino[2,3-c]pyridin-7-yl)-5-(2-hydroxy-ethy/)-oxazolidin-2-one:
[0172] A suspension of intermediate M.ii (2.7 g, 7.3 mmol) in THF (40 mL) was treated with
a solution of TBAF (1M in THF; 7.5 mL) and further stirred at rt for 2.5 h. The reaction
mixture was partitioned between EA and 33% aq. NH
4OH. The org. phase was washed with brine, dried over MgSO
4 and evaporated under reduced pressure. The residue was crystallized from ether, affording
a yellow solid (1.1 g, 58% yield).
1H NMR (CDCl
3) δ: 7.74 (d, J = 8.5 Hz, 1H) 7.24 (d, J = 8.5 Hz, 1H), 4.83 (m, 1H), 4.43 (m, 2H),
4.28 (m, 4H), 3.88 (m, 3H), 2.03 (m, 2H).
MS (ESI, m/z): 267.1 [M+H
+].
M.iv. rac-methanesulfonic acid 2-[3-(2,3-dihydro-[1,4]dioxino[2,3-c]pyridin-7-yl)-2-oxo-oxazolidin-5-yl]-ethyl
ester:
[0173] Starting from intermediate M.iii (1.0 g) and following procedure D, the title compound
was obtained as a beige solid (1.3 g; 100% yield).
MS (ESI, m/z): 345.2 [M+H
+].
Intermediate N: rac-methanesulfonic acid 2-[3-(2,3-dihydro-[1,4]dioxino[2,3-b]pyridin-6-yl)-2-oxo-oxazolidin-5-yl]-ethyl
ester:
N.i. (2,3-dihydro-[1,4]dioxino[2,3-b]pyridin-6-yl)-carbamic acid benzyl ester:
[0174] Starting from 2,3-dihydro-1,4-dioxino[2,3-b]pyridin-6-amine (2.7 g; prepared according
to
Chemische Berichte (1990), 123(12), 2453-2454) and following procedure C, the title compound was obtained as a beige solid (5.3
g; 100% yield).
1H NMR (CDCl
3) δ: 7.50 (d, J = 8.5 Hz, 1H), 7.35 (m, 5H), 7.22 (m, 2H), 5.19 (s, 2H), 4.37 (m,
2H), 4.19 (m, 2H).
N.ii. rac-5-[2-(tert-butyl-dimethyl-silanyloxy)-ethyl]-3-(2,3-dihydro-[1,4]dioxino[2,3-b]pyridin-6-yl)-oxazolidin-2-one:
[0175] Starting from intermediate N.i (3.0 g) and 2-[2-[[(tert-butyl)dimethylsilyl]oxy]ethyl]-oxirane
(2.12 g; prepared according to
WO 2007/144423) and following procedure A, the title compound was obtained as a brown oil (2.9 g;
73% yield).
MS (ESI, m/z): 380.1 [M+H
+].
N.iii. rac-3-(2,3-dihydro-[1,4]dioxino[2,3-b]pyridin-6-yl)-5-(2-hydroxy-ethyl)-oxazolidin-2-one:
[0176] Starting from intermediate N.ii (2.8 g) and following procedure F, the title compound
was obtained as a yellow solid (1.1 g; 56% yield).
MS (ESI, m/z): 266.8 [M+H
+].
N.iv. rac-methanesulfonic acid 2-[3-(2,3-dihydro-[1,4]dioxino[2,3-b]pyridin-6-yl)-2-oxo-oxazolidin-5-yl]-ethyl
ester:
[0177] Starting from intermediate N.iii (1.0 g) and following procedure D, the title compound
was obtained as a beige solid (1.24 g; 96% yield).
1H NMR (CDCl
3) δ: 7.71 (d, J = 8.8 Hz, 1H), 7.24 (d, J = 8.8 Hz, 1H), 4.80 (m, 1H), 4.43 (m, 4H),
4.33 (m, 1H), 4.23 (m, 2H), 3.89 (m, 1H), 3.04 (s, 3H), 2.20 (m, 2H).
Intermediate O: methanesulfonic acid 2-[(R)-3-(4-ethoxy-phenyl)-2-oxo-oxazolidin-5-yl]-ethyl ester:
O.i. (R)-4-(tert-butyl-dimethyl-silanyloxy)-1-(4-ethoxy-phenylamino)-butan-2-ol:
[0178] Starting from 4-ethoxyaniline (3.2mL; commercial) and tert-butyl-dimethyl-((R)-2-oxiranyl-ethoxy)-silane
(5.0 g; prepared according to
WO 2007/144423) and following procedure A, the title compound was obtained after CC (EA/Hept 1:1)
as a brown oil (5.22 g; 62% yield).
MS (ESI, m/z): 340.2 [M+H
+].
O.ii. (R)-5-[2-(tert-butyl-dimethyl-silanyloxy)-ethyl]-3-(4-ethoxy-phenyl)-oxazolidin-2-one:
[0179] Starting from intermediate O.i (5.2 g) and following procedure B, the title compound
was obtained as an off-white solid (4.3 g; 76.5% yield).
MS (ESI, m/z): 366.1 [M+H
+].
O.iii. (R)-3-(4-ethoxy-phenyl)-5-(2-hydroxy-ethyl)-oxazolidin-2-one:
[0180] Starting from intermediate O.ii (4.3 g) and following procedure F, the title compound
was obtained as an off-white solid (1.53g; 52%).
MS (ESI, m/z): 251.9 [M+H
+].
O.iv. Methanesulfonic acid 2-[(R)-3-(4-ethoxy-phenyl)-2-oxo-oxazolidin-5-yl]-ethyl
ester:
[0181] Starting from intermediate O.iii (1.5 g) and following procedure D (using however
1.5 eq. Ms
2O instead of 1.1 eq. of MsCl), the title compound was obtained as an off-white solid
(1.89 g; 96% yield).
MS (ESI, m/z): 330.0 [M+H
+].
Preparation of final compounds:
Example 1: 6-((R)-5-{[3-(7-methoxy-2-oxo-2H-quinolin-1-yl)-propylamino]-methyl}-2-oxo-oxazolidin-3-yl)-4H-benzo[1,4]thiazin-3-one:
1.i. 3-(7-methoxy-2-oxo-2H-quinolin-1-yl)-propionic acid ethyl ester:
[0182] The compound was obtained according to procedure H starting from 7-methoxy-2(1
H)-quinolinone (614 mg, 3.5 mmol) and ethyl acrylate (0.4 mL). The crude brown oil
(0.96 g; 100% yield) was used as such in the next step.
1H NMR (DMSO-d6) δ: 7.81 (d, J=9.4Hz, 1H), 7.63 (d, J=8.5Hz, 1H), 6.99 (d, J=2.3Hz,
1H), 6.88 (dd, J = 8.8, 2.3 Hz, 1H), 6.39 (d, J=9.4Hz, 1H), 4.45 (m 2H), 4.03 (q,
J = 7.0 Hz, 2H), 3.88 (s, 3H), 2.62 (m, 2H), 1.13 (t, J = 7.0 Hz, 3H),
MS (ESI, m/z): 276.3 [M+H
+].
1.ii. 3-(7-methoxy-2-oxo-2H-quinolin-1-yl)-propionaldehyde:
[0183] The compound was obtained according to procedure J starting from intermediate 1.i
(402 mg, 1.46 mmol) and DIBAH (2.6 mL, 4.38 mmol, 3 eq., solution ~1.7M in toluene).
The crude product was purified by CC (Hept/EA 1:1, to EA containing 1% of NH
4OH), affording 104 mg of an orange oil (31% yield).
1H NMR (DMSO-d6) δ: 9.72 (t, J=1.8Hz, 1H), 7.81 (d, J=9.4Hz, 1H), 7.64 (d, J=8.8Hz,
1H), 6.98 (d, J=2.3Hz, 1H), 6.89 (dd, J = 8.8, 2.3 Hz, 1H), 6.39 (d, J = 9.4 Hz, 1H),
4.50 (t, J = 7.0 Hz, 2H), 3.88 (s, 3H), 2.78 (td, J = 7.0, 1.8 Hz, 2H).
MS (ESI, m/z): 232.2 [M+H
+].
1.iii. 6-((R)-5-{[3-(7-methoxy-2-oxo-2H-quinolin-l-yl)-propylamino]-methyl}-2-oxo-oxazolidin-3-yl)-4H-benzo[1,4]thiazin-3-one:
[0184] The compound was obtained according to procedure I starting from intermediate 1.ii
(60 mg, 0.26 mmol) and intermediate B (73 mg, 0.26 mmol). The product was purified
by CC (EA/MeOH 9:1 to 4:1 containing 1% of NH
4OH), affording 24 mg (19% yield) of a colourless foam.
1H NMR (DMSO-d6) δ: 10.53 (m, 1H), 7.79 (d, J = 9.4 Hz, 1H), 7.62 (d, J = 8.5 Hz, 1H),
7.30 (m, 2H), 7.10 (m, 1H), 6.99 (dd, J = 1.2, 0.6 Hz, 1H), 6.87 (m, 1H), 6.39 (d,
J=9.4Hz, 1H), 4.72 (m, 1H), 4.25 (m, 2H), 4.04 (m, 1H), 3.82 (m, 4H), 3.41 (s, 2H),
2.83 (m, 2H), 2.63 (m, 3H), 1.75 (m, 2H).
MS (ESI, m/z): 495.1 [M+H
+].
Example 2: 6-((R)-5-{[3-(7-bromo-2-oxo-2H-quinolin-1-yl)-propylamino]-methyl}-2-oxo-oxazolidin-3-yl)-4H-benzo[1,4]thiazin-3-one:
2.i. 3-(7-bromo-2-oxo-2H-quinolin-1-yl)-propionic acid ethyl ester:
[0185] The compound was obtained according to procedure H starting from 7-bromoquinolin-2(1
H)-one (commercial; 561 mg, 2.5 mmol) and ethyl acrylate (0.27 mL, 2.5 mmol, 1 eq.).
The crude orange oil (0.76 g; 94% yield) was used as such in the next step.
1H NMR (DMSO-d6) δ: 7.90 (d, J = 9.7 Hz, 1H), 7.83 (d, J = 1.8 Hz, 1H), 7.66 (m, 1H),
7.43 (dd, J = 8.2, 1.5 Hz, 1H), 6.61 (d, J = 9.4 Hz, 1H), 4.44 (m, 2H), 4.03 (q, J
= 7.3 Hz, 2H), 2.61 (m, 2H), 1.14 (t, J = 7.0 Hz, 3H).
MS (ESI, m/z): 326.0 [M+H
+].
2.ii 3-(7-bromo-2-oxo-2H-quinolin-1-yl)-propionaldehyde:
[0186] The compound was obtained according to procedure J starting from intermediate 2.i
(444 mg, 1.37 mmol). The crude product was purified by CC (Hept/EA 2:1 to 1:1 to EA
containing 1% NH
4OH), affording an orange solid (178 mg, 46% yield).
1H NMR (DMSO-d6) δ: 9.71 (s, 1H), 7.88 (m, 2H), 7.67 (d, J = 8.2 Hz, 1H), 7.43 (m,
1H), 6.61 (d, J=9.7 Hz, 1H), 4.48 (t, J = 7.3 Hz, 2H), 2.76 (m, 2H).
MS (ESI, m/z): 280.2 [M+H
+].
2.iii. 6-((R)-5-{[3-(7-bromo-2-oxo-2H-quinolin-1-yl)-propylamino]-methyl}-2-oxo-oxazolidin-3-yl)-4H-benzo[1,4]thiazin-3-one:
[0187] The compound was obtained according to procedure I starting from intermediate 2.ii
(100 mg, 0.357 mmol) and intermediate B (100 mg, 0.357 mmol). The crude product was
purified by CC (EA/MeOH 9:1, 4:1 containing 1% NH
4OH), affording a colourless solid. (50 mg, 26% yield).
1H NMR (DMSO-d6) δ: 10.53 (s, 1H), 7.89 (d, J = 9.4 Hz, 1H), 7.81 (d, J = 1.8 Hz, 1H),
7.66 (d, J=8.5Hz, 1H), 7.41 (dd, J = 8.2, 1.5 Hz, 1H), 7.30 (m, 2H), 7.10 (dd, J =
8.8, 2.3 Hz, 1H), 6.61 (d, J=9.4Hz, 1H), 4.74 (m, 1H), 4.24 (m, 2H), 4.06 (t, J=8.8Hz,
1H), 3.80 (dd, J = 8.8, 6.7 Hz, 1H), 3.41 (s, 2H), 2.83 (d, J = 5.3 Hz, 2H), 2.62
(t, J = 6.7 Hz, 2H), 1.73 (m, 2H).
MS (ESI, m/z): 545.1 [M+H
+].
Example 3: 1-(3-{[(R)-3-(2,3-dihydro-benzo[1,4]dioxin-6-yl)-2-oxo-oxazolidin-5-ylmethyl]-amino}-propyl)-7-methoxy-1H-quinolin-2-one:
[0188] The compound was obtained according to procedure I starting from intermediate 1.ii
and the intermediate amine A. The crude product was purified by CC (EA/MeOH 9:1 containing
1% NH
4OH), affording a colourless foam (680 mg, 72% yield).
1H NMR (DMSO-d6) δ: 7.79 (d, J=9.4Hz, 1H), 7.62 (d, J=9.1 Hz, 1H), 7.10 (s, 1H), 6.97
(m, 2H), 6.85 (m, 2H), 6.39 (d, J = 9.7 Hz, 1H), 4.67 (m, 1H), 4.23 (m, 6H), 4.02
(t, J = 9.1 Hz, 1H), 3.84 (s, 3H), 3.78 (m, 1H), 2.81 (m, 2H), 2.63 (m, 2H), 1.74
(m, 2H). MS (ESI, m/z): 465.9 [M+H
+].
Example 4: 7-bromo-1-(3-{[(R)3-(2,3-dihydro-benzo[1,4]dioxin-6-yl)-2-oxo-oxazolidin-5-ylmethyl]-amino}-propyl)-1H-quinolin-2-one:
[0189] The compound was obtained according to procedure I starting from intermediate 2.ii
(0.357 mmol) and the intermediate amine A. The crude product was purified by CC (EA/MeOH
9:1 containing 1% NH
4OH), affording a colourless foam (104 mg, 57% yield).
1H NMR (DMSO-d6) δ: 7.89 (m, 1H), 7.82 (m, 1H), 7.66 (m, 1H), 7.42 (m, 1H), 7.10 (dd,
J = 1.5, 0.6 Hz, 1H), 6.95 (m, 1H), 6.83 (m, 1H), 6.61 (m, 1H), 4.70 (m, 1H), 4.22
(m, 6H), 4.04 (m, 1H), 3.79 (m, 1H), 2.81 (m, 2H), 2.61 (m, 2H), 1.73 (m, 2H).
MS (ESI, m/z): 516.0 [M+H
+].
Example 5: (RS)-6-(5-{2-[3-(7-methoxy-2-oxo-2H-quinolin-1-yl)-azetidin-1-yl]-ethyl}-2-oxo-oxazolidin-3-yl)-4H-benzo[1,4]thiazin-3-one:
5.i. 3-(7-methoxy-2-oxo-2H-quinolin-1-yl)-azetidine-1-carboxylic acid tert-butyl ester:
[0190] A mixture of 7-methoxy-2(1
H)-quinolinone (commercial; 290 mg; 1.65 mmol) and
tert-butyl 3-iodo-1-azetidinecarboxylate (commercial; 391 mg; 1.38 mmol) and Cs
2CO
3 (613 mg; 1.88 mmol) in DMF (2 mL) was heated at 80°C for 4 h. The reaction mixture
was diluted with water and extracted with EA. The combined org. layers were washed
with water and brine, dried over MgSO
4, concentrated under reduced pressure and purified by CC (Hept/EA 1:1), affording
a pale yellow oil (271 mg, 65% yield).
MS (ESI, m/z): 331.3 [M+H
+].
5.ii. 1-azetidin-3-yl-7-methoxy-1H-quinolin-2-one:
[0191] The compound was obtained according to procedure E starting from intermediate 5.i.
The crude product was purified by CC (DCM/MeOHlNH
4OH 1000:100:8), affording a colourless oil (137 mg, 73% yield).
MS (ESI, m/z): 231.4 [M+H
+].
5.iii (RS)-6-(5-{2-[3-(7-methoxy-2-oxo-2H-quinolin-1-yl)-azetidin-1-yl]-ethyl}-2-oxo-oxazolidin-3-yl)-4H-benzo[1,4]thiazin-3-one:
[0192] A solution of intermediate 5.ii (68 mg; 0.3 mmol) and intermediate D (110 mg; 1 eq.)
and DIPEA (56 µL; 1.1 eq.) in DMSO (1 mL) was stirred at 70 °C for 2 days. The reaction
mixture was diluted with EA and the aq. layer was concentrated under reduced pressure
and purified by HPLC, affording 30 mg (20% yield) of a yellow solid.
1H NMR (DMSO d6) δ: 10.66 (s, 1H), 8.42 (s, 1H), 8.34 (m, 1H), 7.94 (d, J = 8.8 Hz,
1H), 7.34 (m, 3H), 7.22 (dd, J=8.5,1.8 Hz, 1H), 7.08 (m, 1H), 4.85 (m, 1H), 4.52 (m,
2H), 4.28 (m, 1H), 4.11 (m, 1H), 3.97 (s, 3H), 3.95-3.58 (m, 5H), 3.42 (s, 2H), 2.17
(m, 2H). MS (ESI, m/z): 506.9 [M+H
+].
Example 6: 3-(7-methoxy-2-oxo-2H-quinoxalin-1-yl)-N-[(R)-2-oxo-3-(3-oxo-3,4-dihydro-2H-benzo[1,4]thiazin-6-yl)-oxazolidin-5-ylmethyl]-propionamide:
6.i. 3-(7-methoxy-2-oxo-2H-quinoxalin-1-yl)-propionic acid ethyl ester:
[0193] The compound was obtained according to procedure H starting from 7-methoxyquinolin-2(1
H)-one (commercial; 617 mg, 3.5 mmol) and ethyl acrylate (0.4 mL, 3.5 mmol, 1 eq.).
The crude oil was purified by CC (EA), affording 644 mg (67% yield) of a brown oil.
1H NMR (DMSO-d6) δ: 8.02 (s, 1H), 7.73 (d, J = 8.8 Hz, 1H), 7.06 (d, J = 2.6 Hz, 1H),
6.98 (dd, J = 8.8, 2.3 Hz, 1H), 4.44 (t, J = 7.3 Hz, 2H), 4.03 (q, J = 7.3 Hz, 2H),
3.90 (s, 3H), 2.67 (t, J = 7.6 Hz, 2H), 1.12 (t, J = 7.6 Hz, 3H).
MS (ESI, m/z): 277.2 [M+H
+].
6.ii. 3-(7-methoxy-2-oxo-2H-quinoxalin-1-yl)-propionic acid:
[0194] The compound was obtained according to procedure K starting from intermediate 6.i.
The crude filtrate was concentrated under reduced pressure, affording an orange solid
(267mg, 98% yield).
1H NMR (DMSO-d6) δ: 12.41 (m, 1 H), 8.02 (s, 1 H), 7.73 (d, J = 9.1 Hz, 1 H), 7.08
(d, J = 2.6 Hz, 1 H), 6.98 (dd,
J= 8.8, 2.6 Hz, 1 H), 4.41 (m, 2 H), 3.90 (s, 3 H), 2.60 (m, 2 H). MS (ESI, m/z): 249.4
[M+H
+].
6.iii. 3-(7-methoxy-2-oxo-2H-quinoxalin-1-yl)-N-[(R)-2-oxo-3-(3-oxo-3,4-dihydro-2H-benzo[1,4]thiazin-6-yl)-oxazolidin-5-ylmethyl]-propionamide:
[0195] The compound was obtained according to procedure L starting from intermediate 6.ii
(63 mg, 0.25 mmol, 1 eq.) and intermediate B (70 mg, 0.25 mmol, 1 eq.). The yield
was 25 mg (20%; orange solid)
1H NMR (DMSO-d6) δ: 10.55 (s, 1H), 8.40 (m, 1H), 8.00 (s, 1H), 7.72 (d, J = 9.1 Hz,
1H), 7.29 (m, 2H), 7.01 (m, 3H), 4.66 (m, 1H), 4.38 (m, 2H), 4.00 (m, 1H), 3.89 (s,
3H), 3.65 (m, 1H), 3.40 (m, 4H), 2.51 (m, 2H).
MS (ESI, m/z): 509.9 [M+H
+].
Example 7: N-[(R)-3-(2,3-dihydro-benzo[1,4]dioxin-6-yl)-2-ozo-oxazolidin-5-ylmethyl]-3-(7-methoxy-2-oxo-2H-quinolin-1-yl)-propionamide:
7.i. N-[(R)-3-(2,3-dihydro-benzo[1,4]dioxin-6-y/)-2-oxo-oxazolidin-5-ylmethyl]-acrylamide:
[0196] A solution of intermediate A (1 g, 4 mmol) in DCM (19 mL) was cooled to 0°C and sequentially
treated with TEA (0.62 mL, 4.4 mmol, 1.1 eq.) and a solution of acryloyl chloride
(0.33 ml, 4 mmol, 1 eq.) in DCM (1 mL). The reaction mixture was further stirred at
rt for 12 h. The solution was diluted with DCM, sequentially washed with diluted HCl
and brine, dried over Na
2SO
4 and concentrated under reduced pressure. The crude product was purified by CC (EA,
EA/MeOH 19:1 containing 1% of NH
4OH), affording 1.033 g (85% yield) of a colourless foam
1H NMR (DMSO-d6) δ: 8.45 (m, 1H), 7.07 (d, J=2.6Hz, 1H), 6.92 (m, 1H), 6.25 (m, 1H),
6.83 (m, 1H), 6.09 (m, 1H), 5.60 (dd, J = 10.0, 2.3 Hz, 1H), 4.70 (m, 1H), 4.20 (m,
4H), 4.05 (t, J = 9.1 Hz, 1H), 3.67 (dd, J = 9.1, 6.2 Hz, 1H), 3.48 (t, J = 5.6 Hz,
2H).
7.ii. N-[(R)-3-(2,3-dihydro-benzo[1,4]dioxin-6-yl)-2-oxo-oxazolidin-5-ylmethyl]-3-(7-methoxy-2-oxo-2H-quinolin-1-yl)-propionamide:
[0197] The compound was obtained according to procedure H starting from intermediate 7.i
(183 mg, 0.6 mmol, 1.05 eq.) and 7-methoxy-2(1
H)-quinolinone (100 mg, 0.57 mmol). The crude product was purified by CC (EA/MeOH 9:1
containing 1% of NH
4OH), affording 47 mg of a colourless foam (17% yield).
1H NMR (DMSO-d6) δ: 8.39 (t, J = 5.6 Hz, 1 H), 7.79 (d, J = 9.4 Hz, 1H), 7.61 (d, J
= 8.8 Hz, 1H), 7.04 (m, 2H), 6.87 (m, 3H), 6.39 (d, J = 9.4 Hz, 1H), 4.63 (m, 1H),
4.39 (t, J = 7.3 Hz, 2H), 4.20 (m, 4H), 3.97 (m, 1H), 3.86 (s, 3H), 3.63 (dd, J =
9.1, 6.4 Hz, 1H), 3.39 (t, J = 5.6 Hz, 2H), 2.49 (m, 2H).
MS (ESI, m/z): 480.3[M+H
+).
Example 8: 3-(7-bromo-2-oxo-2H-quinolin-1-yl)-N-[(R)y3-(2,3-dihydro-benzo[1,4]dioxin-6-yl)-2-oxo-oxazolidin-5-ylmethyl]-propionamide:
8.i. 3-(7-bromo-2-oxo-2H-quinolin-1-yl)-propionic acid:
[0198] The compound (colourless solid; 166 mg, 91% yield) was obtained according to procedure
K starting from intermediate 2.i (200 mg, 0.62 mmol).
1H NMR (DMSO-d6) δ: 7.90 (d, J=9.7Hz, 1H), 7.84 (d, J=1.2Hz, 1H), 7.66 (d, J=8.2Hz,
1H), 7.43 (dd, J=8.2, 1.8 Hz, 1H), 6.62 (d, J=9.7Hz, 1H), 4.40 (m, 2H), 2.54 (m, 2H).
MS (ESI, m/z): 296.4 [M+H
+].
8.ii. 3-(7-bromo-2-oxo-2H-quinolin-1-y/)-N-[(R)-3-(2,3-dihydro-benzo[1,4]dioxin-6-y/)-2-oxo-oxazolidin-5-ylmethyl]-propionamide:
[0199] The compound (colourless solid; 82 mg, 62% yield) was obtained according to procedure
L starting from intermediate 8.i. (75 mg, 0.25 mmol, 1 eq.) and intermediate A (63
mg, 0.25 mmol, 1 eq.).
1H NMR (DMSO-d6) δ: 8.39 (m, 1H), 7.88 (m, 1H), 7.77 (s, 1H), 7.65 (m, 1H), 7.41 (m,
1H), 7.06 (m, 1H), 6.91 (m 1H), 6.83 (m, 1H), 6.60 (d, J=9.7Hz, 1H), 4.64 (m, 1H),
4.37 (m, 2H), 4.20 (m, 4H), 3.98 (m, 1H), 3.63 (m, 1H), 3.39 (m, 2H), 2.45 (m, 2H).
MS (ESI, m/z): 528.3 [M+H
+].
Example 9: 3-(7-bromo-2-oxo-2H-quinolin-1-yl)-N-[(R)-2-oxo-3-(3-oxo-3,4-dihydro-2H-benzo[1,4]thiazin-6-yl)-oxazolidin-5-ylmethyl]-propionamide:
[0200] The compound (colourless solid; 43 mg, 31% yield) was obtained according to procedure
L starting from intermediate 8.i (1 eq.) and intermediate B (1 eq.).
1H NMR (DMSO-d6) δ: 10.55 (s, 1H), 8.41 (s, 1H), 7.88 (d, J=9.4Hz, 1H), 7.77 (d, J
= 1.2 Hz, 1H), 7.65 (d, J=8.5Hz, 1H), 7.42 (dd, J=8.2, 1.8 Hz, 1H), 7.29 (m, 2H),
7.05 (dd, J = 8.5, 2.1 Hz, 1H), 6.60 (d, J = 9.7 Hz, 1H), 4.69 (m, 1H), 4.37 (t, J
= 7.6 Hz, 2H), 4.02 (t, J = 9.1 Hz, 1H), 3.66 (dd, J = 9.4, 6.7 Hz, 1H), 3.41 (m,
4H), 2.49 (m, 2H).
MS (ESI, m/z): 559.1 [M+H
+].
Example 10: N-[(R)-3-(2,3-dihydro-benzo[1,4]dioxin-6-yl)-2-oxo-oxazolidin-5-ylmethyl]-3-(7-methoxy-2-oxo-2H-quinoxalin-1-yl)-propionamide:
[0201] The compound (orange solid; 57 mg, 47% yield) was obtained according to procedure
L starting from intermediates 6.ii (1 eq.) and intermediate A (1 eq.).
1H NMR (DMSO-d6) δ: 8.39 (m, 1H), 8.01 (s, 1H), 7.72 (d, J = 8.8 Hz, 1H), 7.06 (m,
2H), 6.97 (m, 1H), 6.87 (m, 2H), 4.61 (m, 1H), 4.38 (m, 2H), 4.20 (m, 4H), 3.95 (m,
1H), 3.89 (s, 3H), 3.62 (m, 1H), 3.37 (m, 2H), 2.53 (m, 2H).
MS (ESI, m/z): 481.2 [M+H
+].
Example 11: 3-(7-methoxy-2-oxo-2H-quinolin-1-yl)-N-[(R)2-oxo-3-(3-oxo-3,4-dihydro-2H-benzo[1,4]thiazin-6-yl)-oxazolidin-5-ylmethyl]-propionamide:
11.i. 3-(7-methoxy-2-oxo-2H-quinolin-1-yl)-propionic acid:
[0202] The compound (yellow solid; 0.319 g, 88% yield) was obtained according to procedure
K starting from intermediate 1.i. (0.402 g, 1.46 mmol).
1H NMR (DMSO-d6) δ: 12.37 (m, 1H), 7.81 (d, J = 9.4 Hz, 1H), 7.63 (d, J = 8.8 Hz, 1H),
7.01 (d, J = 2.3 Hz, 1H), 6.88 (dd, J = 8.8, 2.3 Hz, 1H), 6.40 (d, J = 9.4 Hz, 1H),
4.42 (m, 2H), 3.88 (s, 3H), 2.55 (m, 2H).
MS (ESI, m/z): 248.2 [M+H
+].
11.ii. 3-(7-methoxy-2-oxo-2H-quinolin-1-yl)-N-[(R)-2-oxo-3-(3-oxo-3,4-dihydro-2H-benzo[1,4]thiazin-6-yl)-oxazolidin-5-ylmethyl]-propionamide:
[0203] The compound (colourless solid; 63 mg, 50% yield) was obtained according to procedure
L starting from intermediates B and 11.i.
1H NMR (DMSO-d6) δ: 10.55 (s, 1H), 8.40 (m, 1H), 7.79 (d, J=9.4Hz, 1H), 7.62 (d, J=8.5Hz,
1H), 7.30 (m, 2H), 7.04 (m, 2H), 6.87 (dd, J = 8.8, 2.3 Hz, 1H), 6.38 (d, J = 9.4
Hz, 1H), 4.68 (m, J = 5.0, 5.0, 2.9, 0.6 Hz, 1H), 4.38 (m, 2H), 4.01 (t, J = 8.8 Hz,
1H), 3.86 (s, 3H), 3.67 (dd, J = 9.1, 6.7 Hz, 1H), 3.42 (m, 4H), 2.50 (m, 2H).
MS (ESI, m/z): 509.0 [M+H
+].
Example 12: (RS)-2-amino-N-[(R)-3-(2,3-dihydro-benzo[1,4]dioxin-6-yl)-2-oxo-oxazolidin-5-ylmethyl]-3-(7-methoxy-2-oxo-2H-quinoxalin-1-yl)-propionamide:
12.i. (RS)-2-tert-butoxycarbonylamino-3-(7-methoxy-2-oxo-2H-quinoxalin-1-yl)-propionic
acid methyl ester:
[0204] The compound (yellow solid; 370 mg, 20% yield) was obtained according to procedure
H starting from 7-methoxyquinoxalin-2(1
H)-one (prepared according to
WO 2006/134378) and
N-(
tert-butoxycarbonyl)dehydroalanine methyl ester.
MS (ESI, m/z): 378.2 [M+H
+].
12.ii. (RS)-2-tert-butoxycarbonylamino-3-(7-methoxy-2-oxo-2H-quinoxalin-1-yl)-propionic
acid:
[0205] A solution of intermediate 12.i (370 mg, 0.98 mmol) in THF/H
2O (5:1; 6 mL) was treated with LiOH (83 mg, 2 mmol, 2 eq.) and further stirred at
rt for 7 h. The reaction mixture was partially concentrated under reduced pressure
and the residue was diluted with water and acidified to pH 3 with HCl. The resulting
solid was collected by filtration and washed with water and ether, affording, after
drying, 231 mg (65% yield) of a pink solid.
1H NMR (DMSO-d6) δ: 13.01 (m, 1 H), 8.01 (s, 1H), 7.70 (d, J=8.8Hz, 1H), 7.13 (d, J=2.3Hz,
1H), 7.08 (d, J=8.5Hz, 1H), 6.96 (dd, J = 8.8, 2.3 Hz, 1H), 4.49 (m, 3H), 3.90 (s,
3H), 1.13 (s, 9H).
MS (ESI, m/z): 364.3 [M+H
+].
12.iii. (RS)-[1-{[(R)-3-(2,3-dihydro-benzo[1,4]dioxin-6-yl)-2-oxo-oxazolidin-5-ylmethy/]-carbamoyl}-2-(7-methozy-2-oxo-2H-quinoxalin-1-yl)-ethyl]-carbamic acid tert-butyl
ester:
[0206] The compound was obtained according to procedure L starting from intermediate 12.ii
(102 mg, 0.28 mmol, 1 eq.) and intermediate A (71 mg, 0.28 mmol, 1 eq.). The crude
product was purified by CC (EA), affording 149 mg (89% yield) of a yellow solid.
MS (ESI, m/z): 596.2 [M+H
+].
12.iv. (RS)-2-amino-N-[(R)-3-(2,3-dihydro-benzo[1,4]dioxin-6-yl)-2-oxo-oxazolidin-5-ylmethyl]-3-(7-methoxy-2-oxo-2H-quinoxalin-1-yl)-propionamide
[0207] The compound was obtained according to procedure E starting from intermediate 12.iii
(148 mg, 0.25 mmol). The crude product was purified by CC (EA/MeOH 19:1 to 9:1 to
4:1 containing 1% of NH
4OH), affording 84 mg (68% yield) of an orange solid.
MS (ESI, m/z): 496.4 [M+H
+].
Example 13: 6-((R)-5-([(R)-2-hydroxy-3-(7-methoxy-2-oxo-2H-quinolin-1-yl)-propylamino]-methyl}-2-oxo-oxazolidin-3-yl)-4H-benzo[1,4]oxazin-3-one hydrochloride:
13.i. [(R)-2-hydroxy-3-(7-methoxy-2-oxo-2H-quinolin-1-yl)-propyl]-carbamic acid tert-butyl
ester:
[0208] A solution of 7-methoxy-2(1
H)-quinolinone (875 mg) and tert-butyl [(2R)-3-chloro-2-hydroxypropyl] carbamate (1.2
eq.) in DMF (1 mL) was treated with Cs
2CO
3 (1.63 g, 1 eq.) and heated at 75°C for 1.5 h. After cooling to rt the mixture was
partitioned between EA and water. The org. phase was washed with water and brine,
dried over MgSO
4 and concentrated under reduced pressure. The residue was purified by CC (EA/Hept
2:1, EA) to afford the title intermediate (second eluting compound) as a yellowish
foam (808 mg, 46% yield).
1H NMR (CDCl
3) δ: 7.65 (d, J=9.4Hz, 1H), 7.48 (d, J=8.8Hz, 1H), 6.93 (m, 1H), 6.85 (dd, J = 8.5,
2.3 Hz, 1H), 6.54 (d, J=9.1Hz, 1 H), 5.55 (br., 1H), 4.51 (m, 1H), 4.30 (m, 2H), 4.15
(m, 2H), 4.09 (m, 1H), 3.91 (s, 3H), 3.62 (m, 2H), 3.10 (m, 2H), 1.45 (m, 9H).
MS (ESI, m/z): 349.1 [M+H
+].
13.ii. 1-((R)-3-amino-2-hydroxy-propyl)-7-methoxy-1H-quinolin-2-one:
[0209] The compound was obtained according to procedure E starting from intermediate 13.i
(800 mg). The crude product was purified by CC (DCM/MeOH 9:1 containing 0.5% of NH
4OH), affording 272 mg (48% yield) of a yellowish solid.
1H NMR (DMSO-d6) δ: 7.79 (d, J=9.4Hz, 1H), 7.60 (d, J=8.5Hz, 1H), 7.16 (d, J=2.3Hz,
1H), 6.86 (dd, J = 8.5, 2.3 Hz, 1H), 6.40 (d, J=9.4Hz, 1H), 4.91 (br., 1H), 4.36 (dd,
J = 13.8, 5.9 Hz, 1H), 4.07 (dd, J = 13.8, 6.4 Hz, 1H), 3.86 (s, 3H), 3.72 (m, 1H),
2.51 (m, 2H).
MS (ESI, m/z): 249.4 [M+H
+].
13.iii. 6-((R)-5-{[(R)-2-hydroxy-3-(7-methoxy-2-oxo-2H-quinolin-1-yl)-propylamino]-methyl}-2-oxo-oxazolidin-3
yl)-4H-benzo[1,4]oxazin-3-one hydrochloride:
[0210] A solution of intermediate 13.ii (124 mg; 0.5 mmol), intermediate C (171 mg; 0.5
mmol) and DIPEA (1.2 eq.) in DMSO (3 mL) was heated at 70°C for 24 h. The mixture
was partitioned between EA and water. The org. layer was washed with water and brine,
dried over MgSO
4 and concentrated under reduced pressure. The residue was purified by CC (EA/MeOH
9:1 containing 1% of NH
4OH) affording 60 mg (24% yield) of a gum (free base). This material was dissolved
in MeOH (0.5 mL) and DCM (0.5 mL), treated with 0.25 mL of
0.5M HCl in MeOH and precipitated by addition of 2 mL of ether. The resulting crystals
were collected by filtration affording 25 mg (9% yield) of the title hydrochloride
as a colourless solid.
MS (ESI, m/z): 495.1 [M+H
+].
Example 14: 6-((R)-5-{[(R)-2-hydroxy-3-(7-methoxy-2-oxo-2H-quinolin-1-yl)-propylamino]-methyl]-2-oxo-oxazolidin-3-yl)-4H-benzo[1,4]thiazin-3-one hydrochloride:
[0211] This salt was prepared in analogy to Example 13, step 13.iii, starting from intermediate
E (210 mg; 0.54 mmol) and intermediate 13.ii (124 mg; 0.5 mmol). 85 mg (31% yield)
of a colourless solid were obtained.
1H NMR (DMSO-d6) δ: 10.52 (s, 1H), 7.79 (d, J = 9.4 Hz, 1H), 7.60 (d, J =8.5 Hz, 1H),
7.29 (m, 2H), 7.10 (m, 2H), 6.86 (dd, J = 8.5, 2.1 Hz, 1H), 6.40 (d, J=9.4Hz, 1H),
4.99 (d, J = 5.3 Hz, 1H), 4.31 (s, 1H), 3.84 (s, 3H), 3.40 (s, 2H), 2.84 (m, 2H),
2.63 (m, 2H).
MS (ESI, m/z): 511.2 [M+H
+].
Example 15: 6-((R)-5-[[(S)-2-hydroxy-3-(7-methoxy-2-oxo-2H-quinolin-1-yl)-propylamino]-methyl}-2-oxo-oxazolidin-3-yl)-4H-benzo[1,4]thiazin-3-one:
[0212] The compound was prepared in analogy to Example 13, steps 13.i to 13.iii, starting
from
tert-butyl [(2
S)-3-chloro-2-hydroxypropyl] carbamate (commercial), intermediate E replacing however
intermediate C in the final step and no dissolution of the free base and treatment
with HCl being performed at the end of said step. A yellowish foam (105 mg, 41 % yield)
was obtained.
1H NMR (DMSO-d6) δ: 10.52 (s, 1H), 7.79 (d, J = 9.4 Hz, 1H), 7.60 (d, J=8.5 Hz, 1H),
7.29 (m, 2H), 7.10 (m, 2H), 6.86 (dd, J = 8.5, 2.1 Hz, 1H), 6.40 (d, J=9.4 Hz, 1H),
4.99 (d, J = 5.3 Hz, 1H), 4.31 (s, 1H), 3.84 (s, 3H), 3.40 (s, 2H), 2.84 (m, 2H),
2.63 (m, 2H).
MS (ESI, m/z): 511.2 [M+H
+].
Example 16: 7-fluoro-6-((R)-5-1{[(S)-2-hydroxy-3-(7-methoxy-2-oxo-2H-quinolin-1-yl)-propylamino]-methyl}-2-oxo-oxazolidin-3-yl)-4H-benzo[1,4]thiazin-3-one:
[0213] The compound was prepared in analogy to Example 13, steps 13.i to 13.iii, using intermediate
F for the final step and no dissolution of the free base and treatment with HCl being
performed at the end of said step. A beige foam (10 mg, 23% yield) was obtained.
1H NMR (CDCl
3) δ: 9.18 (s, 1H), 7.69 (d, J=9.4Hz, 1H), 7.51 (d, J=8.8 Hz, 1H), 7.33 (d, J=6.7Hz,
1H), 7.08 (d, J = 10.5 Hz, 1H), 6.97 (d, J=2.1Hz, 1H), 6.86 (dd, J = 8.8, 2.3 Hz,
1H), 6.74 (d, J=9.4 Hz, 1H), 4.84 (dd, J = 3.8, 2.1 Hz, 1H), 4.57 (dd, J = 14.6, 8.5
Hz, 1H), 4.32 (dd, J =14.6, 4.1 Hz, 1H), 4.18 (m, 2H), 3.88 (m, 5H), 3.43 (m, 1H),
3.34 (m, 1H), 3.15 (dd, J = 13.5, 3.2 Hz, 1H), 3.03 (dd, J =12.3, 4.7 Hz, 1H), 2.84
(m, 2H).
MS (ESI, m/z): 529.3 [M+H
+].
Example 17: 6-methoxy-4-(3-{[(R)2-oxo-3-(3-oxo-3,4-dihydro-2H-benzo[1,4]thiazin-6-yl)-oxazolidin-5-ylmethyl]-amino}-propyl)-4H-pyrido[2,3-b]pyrazin-3-one:
17.i. [3-(6-methoxy-3-nitro-pyridin-2-ylamino)-propyl]-carbamic acid tert-butyl ester:
[0214] A mixture of 2-chloro-6-methoxy-3-nitropyridine (5.9 g; commercial),
N-(
tert-butoxycarbonyl)-1,3-propanediamine (4.48 g; commercial) and K
2CO
3 (3.55 g) in MeCN (90 mL) and DMF (25 mL) was heated at 40°C for 30 min. The reaction
mixture was filtered and the filtrate was evaporated under reduced pressure. The residue
was taken up in EA, sequentially washed with water and brine and evaporated under
reduced pressure, affording 8.1 g (96% yield) of a crude yellow solid which was used
in the next step without further purification.
MS (ESI, m/z): 327.4 [M+H
+].
17.ii. [3-(3-amino-6-methoxy-pyridin-2ylamino)-propyl]-carbamic acid tert-butyl ester:
[0215] A solution of intermediate 17.i (8.1 g) in EtOH (170 mL) was hydrogenated over 10%
Pd/C (2.6 g). After 4 h the catalyst was filtered off and the filtrate was evaporated
under reduced pressure, affording 7.37 g (100% yield) of a dark brown oil which was
used in the next step without further purification.
MS (ESI, m/z): 297.4 [M+H
+].
17.iii. [2-(3-tert-butoxycarbonylamino-propylamino)-6-methoxy-pyridin-3-ylamino]-acetic
acid ethyl ester:
[0216] A solution of intermediate 17.ii (7.37 g) and ethyl bromoacetate (2.75 mL) in MeCN
(130 mL) and DMF (65 mL) was stirred overnight at rt in presence of K
2CO
3 (6.87 g). The reaction mixture was filtered and the filtrate was evaporated under
reduced pressure. The residue was taken up in EA/MeOH (19:1; 200 mL), sequentially
washed with water and brine, dried over MgSO
4 and purified by CC (Hept/EA, 2:1 to 1:1), affording 5.69 g (60% yield) of a black
oil.
MS (ESI, m/z): 383.2 [M+H
+].
17.iv. [3-(6-methoxy-3-oxo-3H-pyrido[2,3-b]pyrazin-4-yl)-propyl]-carbamic acid tert-butyl
ester:
[0217] A solution of intermediate 17.iii (5.69 g) in toluene (350 mL) containing AcOH (1
mL) was refluxed for one day. The resulting solution was diluted with DCM (300 mL),
treated with MnO
2 (24 g) and further stirred overnight. The suspension was filtered, the filtrate was
evaporated under reduced pressure and purified by CC (Hept/EA 2:1 to 1:2) affording
a brown oil (4.02 g; 81 % yield).
MS (ESI, m/z): 335.1 [M+H
+].
17.v. 4-(3-amino-propyl)-6-methoxy-4H-pyrido[2,3-b]pyrazin-3-one:
[0218] Intermediate 17.iv (1.7 g) was deprotected according to procedure E to give the desired
amine as a brown solid (85% yield).
MS (ESI, m/z): 235.1 [M+H
+].
17.vi. 6-methoxy-4-(3-{[(R)-2-oxo-3-(3-oxo-3,4-dihydro-2H-benzo[1,4]thiazin-6-yl)-oxazolidin-5-ylmethyl]-amino}-propyl)-4H-pyrido[2,3-b]pyrazin-3-one:
[0219] Starting from amine 17.v (169 mg) and intermediate E (294 mg) and following procedure
M, the title compound was obtained as a light orange foam (57 mg; 16% yield).
1H NMR (DMSO-d6) δ: 10.53 (s, 1H), 8.11 (m, 2H), 7.30 (m, 2H), 7.09 (dd, J = 8.5, 2.3
Hz, 1H), 6.82 (d, J = 8.5 Hz, 1H), 4.68 (s, 1H), 4.34 (t, J = 7.0 Hz, 2H), 3.96 (s,
3H), 3.75 (dd, J = 8.8, 6.4 Hz, 1H), 3.41 (s, 2H), 2.80 (m, 2H), 2.63 (m, 2H), 1.83
(m, 2H).
MS (ESI, m/z): 497.4 [M+H
+].
Example 18: 4-(3-([(R)-3-(2,3-dihydro-benzo[1,4]dioxin-6-yl)-2-oxo-oxazolidin-5-ylmethyl]-amino}-propyl)-6-methoxy-4H-pyrido[2,3-b]pyrazin-3-one
[0220] Starting from amine 17.v (169 mg) and intermediate G (272 mg) and following procedure
M, the title compound was obtained as a yellow foam (126 mg; 39% yield). MS (ESI,
m/z): 468.1 [M+H
+].
Example 19: 6-methoxy-4-(3-([(R)-2-oxo-3-(3-oxo-3,4-dihydro-2H-benzo[1,4]oxazin-6-yl)-oxazolidin-5-ylmethyl]-amino}-propyl)-4H-pyrido[2,3-b]pyrazin-3-one
[0221] Starting from amine 17.v (157 mg) and intermediate C (239 mg) and following procedure
M, the title compound was obtained as a yellow foam (30 mg; 9% yield)
1H NMR (DMSO-d6) δ: 10.69 (s, 1H), 8.11 (m, 2H), 7.30 (d, J = 0.6 Hz, 1H), 6.92 (s,
2H), 6.82 (m, 1H), 4.66 (m, 1H), 4.51 (s, 2H), 4.34 (m, 2H), 3.96 (s, 3H), 3.75 (m,
1H), 2.79 (m, 2H), 2.64 (m, 2H), 1.84 (m, 2H).
MS (ESI, m/z): 481.3 [M+H
+].
[0222] Example 20: 6-methoxy-4-(2-{2-[(R)-2-oxo-3-(3-oxo-3,4-dihydro-2H-benzo[1,4]thiazin-6-yl)-oxazolidin-5-yl]-ethylamino}-ethyl)-4H-pyrido[2,3-b]pyrazin-3-one:
20.i. [2-(6-methoxy-3-nitro-pyridin-2-ylamino)-ethyl]-carbamic acid tert-butyl ester:
[0223] Starting from 2-chloro-6-methoxy-3-nitropyridine (5.0 g; commercial) and N-Boc-ethylenediamine
(4.15 mL; commercial), and proceeding in analogy to Example 17, step 17.i, the title
compound was obtained as a yellow solid (4.79 g; 59% yield).
MS (ESI, m/z): 313.3 [M+H
+].
20.ii. [2-(3-amino-6-methoxy-pyridin-2-ylamino)-ethyl]-carbamic acid tert-butyl ester:
[0224] Starting from intermediate 20.i (4.78 g) and proceeding in analogy to Example 17,
step 17.ii, the title compound was obtained as a grey blue solid (4.21 g; 97% yield).
MS (ESI, m/z): 283.3 [M+H
+].
20.iii. [2-(2-tert-butoxycarbonylamino-ethylamino)-6-methoxy-pyridin-3-ylamino]-acetic
acid ethyl ester:
[0225] Starting from intermediate 20.ii (4.17 g) and ethyl bromoacetate (1.64 mL) and proceeding
in analogy to Example 17, step 17.iii, the title compound was obtained as a brown
oil (3.85 g; 70% yield).
MS (ESI, m/z): 369.3 [M+H
+].
20.iv. [2-(6-methoxy-3-oxo-3H-pyrido[2,3-b]pyrazin-4-yl)-ethyl]-carbamic acid tert-butyl
ester:
[0226] Starting from intermediate 20.iii (3.83 g) and proceeding in analogy to Example 17,
step 17.iv, the title compound was obtained as an orange solid (2.50 g; 75% yield).
MS (ESI, m/z): 321.3 [M+H
+].
20.v. 4-(2-amino-ethyl)-6-methoxy-4H-pyrido[2,3-b]pyrazin-3-one:
[0227] Starting from intermediate 20.iv (2.49 g) and proceeding in analogy to Example 17,
step 17.v, the title compound was obtained as an orange oil (760 mg; 44% yield).
MS (ESI, m/z): 221.1 [M+H
+].
20.vi. 6-methoxy-4-(2-{2-[(R)-2-oxo-3-(3-oxo-3,4-dihydro-2H-benzo[1,4]thiazin-6-yl)-oxazolidin-5-yl]-ethylamino}-ethyl)-4H-pyrido[2,3-b]pyrazin-3-one:
[0228] Starting from intermediate 20.v (275 mg) and intermediate H (465 mg) and following
procedure M, the title compound was obtained as a brown solid (122 mg; 19% yield)
1H NMR (DMSO-d6) δ: 10.54 (s, 1H), 8.11 (m, 2H), 7.31 (m, 2H), 7.03 (dd, J = 8.8, 2.3
Hz, 1H), 6.82 (d, J = 8.8 Hz, 1H), 4.69 (m, 1H), 4.39 (m, 2H), 3.98 (m, 3H), 3.65
(m, 1H), 3.41 (m, 2H), 2.88 (m, 2H), 2.70 (m, 2H), 1.82 (m, 2H).
MS (ESI, m/z): 497.4 [M+H
+].
Example 21: 6-methoxy-4-(2-{2-[(R)-2-oxo-3-(3-oxo-3,4-dihydro-2H-benzo[1,4]oxazin-6-yl)-oxazolidin-5-yl]-ethylamino}-ethyl)-4H-pyrido[2,3-b]pyrazin-3-one:
[0229] Starting from intermediate 20.v (275 mg) and intermediate H (534 mg) and following
procedure M, the title compound was obtained as a brown foam (24 mg; 4% yield)
MS (ESI, m/z): 481.4 [M+H
+].
Example 22: 6-methoxy-4-(1-{2-[(R)-2-oxo-3-(3-oxo-3,4-dihydro-2H-benzo[1,4]thiazin-6-yl)-oxazolidin-5-yl]-ethyl}-azetidin-3-yl)-4H-pyrido[2,3-b]pyrazin-3-one:
22.i. 4-azetidin-3-yl-6-methoxy-4H-pyrido[2,3-b]pyrazin-3-one:
[0230] Starting from 2-chloro-6-methoxy-3-nitropyridine (7.7 g; commercial) and 3-amino-1-Boc-azetidine
(6.9 g, commercial) and following the procedures of Example 17, steps 17.i to 17.v,
the title compound was obtained as a yellow solid (1 g; 10% yield over 5 steps).
MS (ESI, m/z): 233.1 [M+H
+].
22.ii. 6-methoxy-4-(1-{2-[(R)-2-oxo-3-(3-oxo-3,4-dihydro-2H-benzo[1,4]thiazin-6-yl)-oxazolidin-5-yl]-ethyl}-azetidin-3-yl)-4H-pyrido[2,3-b]pyrazin-3-one:
[0231] Starting from intermediate 22.i (100 mg) and intermediate J (175 mg) and following
procedure M, the title compound was obtained as a beige solid (70 mg; 31 % yield)
MS (ESI, m/z): 509.2 [M+H
+].
[0232] Example 23: 6-methoxy-4-(1-{3-[(R)-2-oxo-3-(3-oxo-3,4-dihydro-2H-benzo[1,4]thiazin-6-yl)-oxazolidin-5-yl]-propyl}-azetidin-3-yl)-4H-pyrido[2,3-b]pyrazin-3-one:
[0233] Starting from intermediate 22.i (100 mg) and intermediate K (167 mg) and following
procedure M, the title compound was obtained as a beige solid (16 mg; 7% yield)
MS (ESI, m/z): 523.2 [M+H
+].
Example 24: 6-methoxy-4-(1-{2-[(S)-2-oxo-3-(3-oxo-3,4-dihydro-2H-benzo[1,4]thiazin-6-yl)-oxazolidin-5-yl]-ethyl}-azetidin-3-yl)-4H-pyrido[2,3-b]pyrazin-3-one:
[0234] Starting from intermediate 22.i (100 mg) and intermediate L (161 mg) and following
procedure M, the title compound was obtained as a beige solid (27 mg; 12% yield)
MS (ESI, m/z): 509.2 [M+H
+].
Example 25: 4-((R)-2-hydroxy-3-{[(R)-2-oxo-3-(3-oxo-3,4-dihydro-2H-benzo[1,4]thiazin-6-yl)-oxazolidin-5-ylmethyl]-amino}-propyl)-6-methoxy-4H-pyrido[2,3-b]pyrazin-3-one:
25.i. [(S)-2-hydroxy-3-(6-methoxy-3-nitro-pyridin-2-ylamino)-propyl]-carbamic acid
tert-butyl ester:
[0235] Starting from 2-chloro-6-methoxy-3-nitropyridine (5.4 g; commercial) and ((
S)-3-amino-2-hydroxy-propyl)-carbamic acid tert-butyl ester (5.3 g, 1 eq.; prepared
according to
Adv. Synth. Catal. 2004, 346, 1195) and proceeding in analogy to Example 17, step 17.i, the title compound was obtained
as a yellow solid (8.20 g; 86% yield).
MS (ESI, m/z): 343.2 [M+H
+].
25.ii. [(S)-3-(3-amino-6-methoxy-pyridin-2-ylamino)-2-(tert-butyl-dimethyl-silanyloxy)-propyl]-carbamic
acid tert-butyl ester:
[0236] A solution of intermediate 25.i (8.0 g) in EtOH (200 mL) was hydrogenated over 10%
Pd/C (2.5 g). After 3 h the catalyst was filtered off and the filtrate was evaporated
under reduced pressure. To a solution of the resulting oil (6.8 g) and imidazole (2.96
g) in THF (55 mL) a solution of TBDMSCl (6.56 g, 2 eq.) in THF (50 mL) was added dropwise
at rt. The resulting mixture was stirred at rt overnight. The solids were filtered
off and the filtrate was washed with water and brine, dried over MgSO
4 and concentrated under reduced pressure to afford the title intermediate as a dark
blue oil (10.0 g, quant.) which was used immediately in the next step.
MS (ESI, m/z): 427.1 [M+H
+].
25.iii. {2-[(S)-3-tert-butoxycarbonylamino-2-(tert-butyl-dimethyl-silanyloxy)-propylamino]-6-methoxy-pyridin-3-ylamino}-acetic
acid ethyl ester:
[0237] A solution of intermediate 25.ii (9.26 g) and ethyl bromoacetate (2.40 mL) in MeCN
(110 mL) and DMF (50 mL) was stirred overnight at rt in presence of K
2CO
3 (6.00 g). The reaction mixture was filtered and the filtrate was evaporated under
reduced pressure. The residue was taken up in EA (200 mL), sequentially washed with
water and brine, dried over MgSO
4 and purified by CC (Hept/EA, 2:1 to 1:1) affording 9.60 g (86% yield) of a dark blue
oil.
1H NMR (CDCl
3) δ: 6.92 (m, 1H), 5.91 (d, J=8.2Hz, 1H), 4.21 (q, J=7.0Hz, 2H), 3.99 (m, 1H), 3.84
(s, 3H), 3.72 (s, 2H), 3.40-3.05 (m, 4H), 1.43 (s, 9H), 1.28 (m, 5H), 0.91 (s, 9H),
0.10 (s, 6H).
25.iv [(R)-2-(tert-butyl-dimethyl-silanyloxy)-3-(6-methoxy-3-oxo-3H-pyrido[2,3-b]pyrazin-4-yl)-propyl]-carbamic
acid tert-butyl ester:
[0238] A solution of intermediate 25.iii (9.60 g) in toluene (360 mL) containing AcOH (2.1
mL) was refluxed overnight. The resulting solution was concentrated and diluted with
DCM (200 mL), treated with MnO
2 (20 g) and further stirred at rt for 5 h. The suspension was filtered and the filtrate
was evaporated under reduced pressure and purified by CC (Hept/EA 1:1), affording
a yellowish oil (5.30 g; 47% yield).
MS (ESI, m/z): 465.2 [M+H
+].
25.v. 4-[(R)-3-amino-2-(tert-butyl-dimethyl-silanyloxy)-propyl]-6-methoxy-4H-pyrido[2,3-b]pyrazin-3-one:
[0239] Intermediate 25.iv (1.0 g) was deprotected according to Procedure E to give the desired
amine as a brown oil (quant.).
MS (ESI, m/z): 365.0 [M+H
+].
25. vi. 4-((R)-2-(tert-butyl-dimethyl-silanyloxy)-3-{[(R)-2-oxo-3-(3-oxo-3,4-dihydro-2H-benzo[1,4]thiazin-6-yl)-oxazolidin-5-ylmethyl]-amino}-propyl)-6-methoxy-4H-pyrido[2,3-b]pyrazin-3-one:
[0240] Starting from intermediate 25.v (270 mg) and intermediate E (289 mg) and following
procedure M, the title compound was obtained as a beige foam (57 mg; 16% yield).
MS (ESI, m/z): 627.1 [M+H
+].
25.vii. 4-((R)-2-hydroxy-3-{[(R)-2-oxo-3-(3-oxo-3,4-dihydro-2H-benzo[1,4]thiazin-6-yl)-oxazolidin-5-ylmethyl]-amino}-propyl)-6-methoxy-4H-pyrido[2,3-b]pyrazin-3-one:
[0241] Starting with intermediate 25.vi (180 mg) and using procedure F, the title compound
was obtained as a yellow solid (70 mg, 48% yield).
MS (ESI, m/z): 513.3 [M+H
+].
Example 26: 4-((R)-3-{[(R)-3-(2,3-dihydro-benzo[1,4]dioxin-6-yl]-2-oxo-oxazolidin-5-ylmethyl]-amino}-2-hydroxy-propyl)-6-methoxy-4H-pyrido[2,3-b]pyrazin-3-one
26.i. 4-((R)-2-(tert-butyl-dimethyl-silanyloxy)-3-{[(R)-3-(2,3-dihydro-benzo[1,4]dioxin-6-yl)-2-oxo-oxazolidin-5-ylmethyl]-amino}-propyl)-6-methoxy-4H-pyrido[2,3-b]pyrazin-3-one:
[0242] Starting from intermediate 25.i (270 mg) and intermediate G (267 mg) and following
procedure M, the title compound was obtained as a beige foam (220 mg; 50% yield).
MS (ESI, m/z): 598.2 [M+H
+].
26.ii. 4-((R)-3-{[(R)-3-(2,3-dihydro-benzo[1,4]dioxin-6-yl)-2-oxo-oxazolidin-5-ylmethyl]-amino}-2-hydroxy-propyl)-6-methoxy-4H-pyrido[2,3-b]pyrazin-3-one:
[0243] Starting with intermediate 26.i (200 mg) and using procedure F, the title compound
was obtained as a yellow solid (60 mg, 37% yield).
MS (ESI, m/z): 484.1 [M+H
+].
Example 27: 4-((R)-2-hydroxy-3-{[(R)-2-oxo-3-(3-oxo-3,4-dihydro-2H-benzo[1,4]oxazin-6-yl)-oxazolidin-5-ylmethyl]-amino}-propyl)-6-methoxy-4H-pyrido[2,3-b]pyrazin-3-one:
27.i. 4-((R)-2-(tert-butyl-dimethyl-silanyloxy)-3-{[(R)-2-oxo-3-(3-oxo-3,4-dihydro-2H-benzo[1,4]oxazin-6yl)-oxazolidin-5-ylmethyl]-amino}-propyl)-6-methoxy-4H-pyrido[2,3-b]pyrazin-3-one:
[0244] Starting from intermediate 25.i (240 mg) and intermediate C (225 mg) and following
procedure M, the title compound was obtained as a yellow resin (130 mg; 32% yield).
MS (ESI, m/z): 611.2 [M+H
+].
27.ii. 4-((R)-2-hydroxy-3-{[(R)-2-oxo-3-(3-oxo-3,4-dihydro-2H-benzo[1,4]oxazin-6-yl)-oxazolidin-5-ylmethyl]-amino}-propyl)-6-methoxy-4H-pyrido[2,3-b]pyrazin-3-one:
[0245] Starting with intermediate 27.i (110 mg) and using procedure F, the title compound
was obtained as a yellow solid (60 mg, 74% yield).
MS (ESI, m/z): 497.3 [M+H
+].
Example 28: 1-(3-{[(R)-3-(2,3-dihydro-benzo[1,4]dioxin-6-yl)-2-oxo-oxazolidin-5-ylmethyl]-amino}-propyl)-7-methoxy-3,4-dihydro-1H-quinolin-2-one:
[0246] A solution of the compound of Example 3 in MeOH/AcOH (1:1, 3 mL) was hydrogenated
over Pd/C (59 mg) at 40°C for 4 h. After cooling to rt the catalyst was filtered off
and the filter cake was washed with MeOH and MeOH/DCM. The combined filtrates were
concentrated. Water and NH
4OH were added and the mixture was extracted with DCM/MeOH 9: 1. The combined org.
layers were dried over MgSO
4 and concentrated under reduced pressure to afford the title compound as a colourless
resin (22 mg, 84% yield).
MS (ESI, m/z): 468.0 [M+H
+].
Example 29: 4-(3-([(R)-3-(3-fluoro-4-methyl-phenyl)2-oxo-oxazolidin-5-ylmethyl]-amino}-propyl)-6-methoxy-4H-pyrido[2,3-b]pyrazin-3-one:
[0247] Starting with (5S)-3-(3-fluoro-4-methylphenyl)-5-(iodomethyl)-2-oxazolidinone (107
mg; prepared according to
WO 2008/126034) and intermediate 17.v (75 mg) and using procedure M, the title compound was obtained
as a pale yellow resin (35 mg; 25% yield).
1H NMR (CDCl
3) δ: 8.12 (s, 1H), 7.99 (d, J=8.8 Hz, 1H), 7.35 (m, 1H), 7.12 (m, 2H), 6.71 (m, 1H),
4.72 (m, 1H), 4.49 (t, J=7.0Hz, 2H), 3.99 (m, 4H), 3.85 (dd, J = 8.5, 7.0 Hz, 1H),
2.93 (m, 2H), 2.75 (td, J = 6.7, 3.2 Hz, 2H), 2.21 (d, J = 1.8 Hz, 3H), 1.99 (m, 2H),
1.73 (s, 1H).
MS (ESI, m/z): 442.1 [M+H
+].
Example 30: 6-methoxy-4-{1-[(R)-2-oxo-3-(3-oxo-3,4-dihydro-2H-benzo[1,4]thiazin-6-yl)-oxazolidin-5-ylmethyl]-azetidin-3-yl}-4H-pyrido[2,3-b]pyrazin-3-one:
[0248] Starting with 6-[
(5S)-5-(iodomethyl)-2-oxo-3-oxazolidinyl]-2
H-1,4-benzothiazin-3(4
H)-one (337 mg; prepared according to
WO 2008/126034) and intermediate 22.i (200 mg) and using procedure M, the title compound was obtained
as a light yellow foam (130 mg; 30% yield).
1H NMR (DMSO-d6) δ: 10.55 (s, 1H), 8.10 (d, J = 8.5 Hz, 1H), 8.02 (s, 1H), 7.31 (m,
2H), 7.12 (dd, J = 8.5, 2.3 Hz, 1H), 6.81 (d, J = 8.5 Hz, 1H), 4.73 (m, 2H), 4.08
(m, 3H), 3.90 (s, 3H), 3.42 (s, 2H), 3.35 (m, 2H), 2.74 (m, 2H).
MS (ESI, m/z): 459.1 [M+H
+].
Example 31: rac-4-(2-{2-[3-(2,3-dihydro-[1,4]dioxino[2,3-c]pyridin-7-yl)-2-oxo-oxazolidin-5-yl]-ethylamino}-ethyl)-6-methoxy-4H-pyrido[2,3-b]pyrazin-3-one:
[0249] Starting from intermediate M (100 mg) and intermediate 20.v (63.8 mg) and using procedure
D, the title compound was obtained after CC (DCM/MeOH 19:1 to 9:1) as a beige foam
(42 g; 31 % yield).
1H NMR (DMSO-d6) δ: 8.10 (m, 2H), 7.89 (s, 1H), 7.50 (s, 1H), 6.81 (d, J = 8.8 Hz,
1H), 4.67 (m, 1H), 4.37 (m, 6H), 4.25 (m, 2H), 4.14 (m, 1H), 3.98 (s, 3H), 3.71 (m,
1H), 2.88 (m, 2H), 2.70 (m, 2H), 1.80 (m, 2H).
MS (ESI, m/z): 468.9 [M+H
+].
Example 32: rac-4-(2-{2-[3-(2,3-dihydro-[1,4]dioxino[2,3-b]pyridin-6-yl)-2-oxo-oxazolidin-5-yl]-ethylamino}-ethyl)-6-methoxy-4H-pyrido[2,3-b]pyrazin-3-one:
[0250] Starting from Intermediate N (100 mg) and intermediate 20.v (63.9 mg) and using procedure
M, the title compound was obtained as a beige solid (44 mg; 32% yield).
1H NMR (DMSO-d6) δ: 8.66 (d, J=4.7 Hz, 1H), 8.22 (d, J = 9.1 Hz, 1H), 7.54 (m, 2H),
7.34 (d, J=8.5 Hz, 1H), 7.23 (d, J=9.1 Hz, 1H), 4.71 (m, 1H), 4.37 (m, 2H), 4.16 (m,
3H), 4.02 (s, 3H), 3.71 (m, 1H), 3.02 (m, 2H), 2.78 (m, 2H), 1.88 (m, 2H).
MS (ESI, m/z): 452.0 [M+H
+].
Example 33: rac-6-(5-{2-[2-(6-methoxy-3-oxo-3H-pyrido[2,3-b]pyrazin-4-yl)-ethylamino]-ethyl}-2-oxo-oxazolidin-3-yl)-4H-pyrido[3,2-b][1,4]oxazin-3-one:
33.i. 6-bromo-4-(4-methoxy-benzyl)-4H-pyrido[3,2-b][1,4]oxazin-3-one:
[0251] A suspension of 6-bromo-2
H-pyrido[3,2-
b]-1,4-oxazin-3(4
H)-one (2.0 g; prepared according to
WO 01/30782) in DMF (40 mL) was treated with 4-methoxybenzyl chloride (1.18 mL) and Cs
2CO
3 (8.5 g) and stirred at rt for 2 h. The solvent was evaporated under reduced pressure
and the residue was partitioned between EA and water. The org. layer was washed with
brine, dried over MgSO
4 and evaporated under reduced pressure. The residue was triturated with Hept, affording
a beige solid (2.8 g, 92% yield).
1H NMR (CDCl
3) δ: 7.49 (d, J=8.8Hz, 2H), 7.05 (s, 2H), 6.83 (d, J=8.8Hz, 2H), 6.83 (d, J = 8.8
Hz, 2H), 6.83 (d, J=8.8 Hz, 2H), 4.67 (s, 2H), 3.77 (s, 3H).
33.ii. rac-1-azido-4-(tert-butyl-dimethyl-silanyloxy)-butan-2-ol:
[0252] A solution of 2-[2-[[(tert-butyl)dimethylsilyl]oxy]ethyl]-oxirane (5.0 g; prepared
according to
WO 2007/144423) in MeOH (150 mL) was reacted with NaN
3 (3.95 g) and NH
4Cl (2.37 g). The reaction mixture was further stirred at 80°C overnight. The solvent
was evaporated under reduced pressure and the residue was partitioned between EA and
water. The org layer was washed with brine, dried over Na
2SO
4 and evaporated under reduced pressure, affording a yellow oil (4.9 g, 81 % yield).
1H NMR (CDCl3) δ: 4.01 (m, 1H), 3.87 (m, 2 H), 3.30 (m, 2 H), 1.72 (m, 2 H), 0.90 (m,
9 H), (m, 6 H).
33.iii. rac-1-amino-4-(tert-butyl-dimethyl-silanyloxy)-butan-2-ol:
[0253] A solution of intermediate 33.ii (4.85 g) in THF (100 mL) was hydrogenated for 3
h over 10% Pd/C (1.0 g). The catalyst was filtered off and the filtrate was evaporated
under reduced pressure, affording a yellow oil (4.1 g, 94.5% yield).
MS (ESI, m/z): 219.8 [M+H
+].
33.iv. rac-5-[2-(tert-butyl-dimethyl-silanyloxy)-ethyl]-oxazolidin-2-one:
[0254] Starting from intermediate 33.iii (4.0 g) and using procedure B, the title compound
was obtained as a light yellow oil (3.3 g; 73.8% yield).
1H NMR (CDCl
3) δ: 5.22 (br., 1H), 4.80 (m, 1H), 3.74 (m, 3H), 3.33 (m, 1H), 1.93 (m, 2H), 0.89
(m, 9H), 0.07 (m, 6H).
33.v. rac-6-{5-[2-(tert-butyl-dimethyl-silanyloxy)-ethyl]-2-oxo-oxazolidin-3-yl}-4-(4-methoxy-benzyl)-4H-pyrido[3,2-b][1,4]
oxazin-3-one:
[0255] Intermediates 33.iv (1.97 g) and 33.i (2.8 g), CuI (305 mg) and K
2CO
3 (2.2 g) were placed in a round bottom flask and the flask was flushed with argon.
Trans-1,2-diaminocyclohexane (1.2 mL) and dioxane (60 mL) were added to the mixture
and the reaction flask was again flushed with argon. The reaction mixture was stirred
at 100°C for 2 days and partitioned between EA and water. The org. layer was washed
with brine, dried over MgSO
4 and evaporated under reduced pressure. The residue was purified by CC (DCM/MeOH 19:1),
affording, after crystallisation from Hept, a colourless solid (1.7 g, 41 % yield).
1H NMR (CDCl
3) δ: 7.81 (d, J = 8.8 Hz, 1H), 7.28 (m, 3H), 6.81 (m, 2H), 5.20 (s, 2H), 4.82 (m,
1H), 4.28 (m, 1H), 3.85 (m, 3H), 3.77 (s, 3H), 2.00 (m, 2H), 0.89 (s, 9H), 0.07 (s,
6H).
33.vi. rac-6-[5-(2-hydroxy-ethyl)-2-oxo-oxazolidin-3-yl]-4-(4-methoxy-benzyl)-4H-pyrido[3,2-b][1,4]
oxazin-3-one:
[0256] Starting from intermediate 33.v (1.7 g) and using procedure F, the title compound
was obtained after purification by CC (EA then EA/MeOH 9:1) as a yellow oil (1.4 g;
100% yield).
MS (ESI, m/z): 400.0 [M+H
+].
33.vii. rac-methanesulfonic acid 2-{3-[4-(4-methoxy-benzyl)-3-oxo-3,4-dihydro-2H-pyrido[3,2-b]
[1,4] oxazin-6-yl]-2-oxo-oxazolidin-5-yl}-ethyl ester:
[0257] Starting from intermediate 33.vi (1.32 g) and using procedure D, the title compound
was obtained as a colourless foam (1.3 g; 82.5% yield)
MS (ESI, m/z): 477.8 [M+H
+].
33.viii. rac-4-(4-methoxy-benzyl)-6-(5-{2-[2-(6-methoxy-3-oxo-3H-pyrido[2,3-b]pyrazin-4-yl)-ethylamino]-ethyl}-2-oxo-oxazolidin-3-yl)-4H-pyrido[3,2-b]
[1,4] oxazin-3-one:
[0258] Starting from intermediates 33.vii (433 mg) and 20.v (200 mg) and following procedure
M, the title compound was obtained after purification by CC (DCM/MeOH 19:1) as an
orange oil (200 mg, 36% yield).
MS (ESI, m/z): 602.1 [M+H
+].
33.ix. rac-6-(5-{2-[2-(6-methoxy-3-oxo-3H-pyrido[2,3-b]pyrazin-4-yl)-ethylamino]-ethyl}-2-oxo-oxazolidin-3-yl)-4H-pyrido[3,2-b]
[1,4] oxazin-3-one:
[0259] A solution of intermediate 33.viii (200 mg) in TFA (5 mL) was heated at 70°C for
5 d.ays. The solvent was evaporated under reduced pressure and the residue was partitioned
between DCM and 33% aq. NH
4OH. The org. phase was washed with water, dried over MgSO
4 and evaporated under reduced pressure. The residue was purified by CC (DCM/MeOH 19:1)
and crystallized from ether /EA, affording a rusty solid (62 mg, 39% yield).
MS (ESI, m/z): 482.1 [M+H
+].
Example 34: 4-(1-{2-[(R)-3-(4-ethoxy-phenyl)2-oxo-oxazolidin-5-yl]-ethyl}-azetidin-3-yl)-6-methoxy-4H-pyrido[2,3-b]pyrazin-3-one:
[0260] Starting from intermediate 22.i (74.5 mg) and intermediate O (105.6 mg) and using
procedure M, the title compound was obtained after purification by CC (DCM/MeOH/NH
4OH 1000:50:4 to 1000:100:8) as a yellow foam (20 mg; 14% yield).
MS (ESI, m/z): 466.1 [M+H
+].
Example 35: 6-methoxy-2-methyl-4-(3-{[(R)-2-oxo-3-(3-oxo-3,4-dihydro-2H-benzo[1,4]thiazin-6-yl)-oxazolidin-5-ylmethyl]-amino}-propyl)-4H-pyrido[2,3-b]pyrazin-3-one:
35.i. [3-(tert-butyl-dimethyl-silanyloxy)-propyl]-(6-methoxy-3-nitro-pyridin-2-yl)-amine:
[0261] A solution of 2-chloro-6-methoxy-3-nitropyridine (commercial; 5.77 g) and aminopropanol
(2.25 g) in MeCN/DMF (10:3, 130 mL) was heated at 50°C for 1 h in presence of K
2CO
3 (4.16 g). The reaction mixture was filtered and the filtrate was evaporated under
reduced pressure. The residue was partitioned between water and ether. The org. phase
was sequentially washed with water and brine, dried over MgSO
4 and evaporated to dryness. The crude 3-(6-methoxy-3-nitro-pyridin-2-ylamino)-propan-1-ol
was dissolved in THF (5 mL) and added dropwise to a solution of TBDMSCI (9.5 g) and
imidazole (4.5 g) in THF (100 mL). The mixture was stirred for 1 h at rt and partitioned
between water and ether. The org. phase was sequentially washed with water and brine,
dried over MgSO
4, concentrated under reduced pressure and purified by CC (EA/Hept 1:9 to 1:4), affording
a yellow solid (9.45 g, 92% yield).
1H NMR (CDCl
3) δ: 8.76 (m, 1H), 8.30 (d, J = 9.1 Hz, 1H), 6.03 (d, J = 9.1 Hz, 1H), 3.96 (s, 3H),
3.74 (m,4H), 1.89 (m, 2H), 0.90 (m, 9H), 0.07 (m, 6H),
35.ii. N2-[3-(tert-butyl-dimethyl-silanyloxy)-propyl]-6-methoxy-pyridine-2,3-diamine:
[0262] A solution of intermediate 35.i in MeOH/THF (300 mL; 1:1) was hydrogenated over 10%
Pd/C (733 mg) for 3 h. The catalyst was filtered off and the filtrate was evaporated
under reduced pressure, affording a violet air-sensitive oil (8.37 g, 97% yield).
1H NMR (CDCl
3) δ: 6.86 (d, J = 7.9 Hz, 1H), 5.88 (d, J = 7.9 Hz, 1H), 4.75 (m, 1H), 3.83 (s, 3H),
3.77 (t, J = 6.2 Hz, 2H), 2.80 (m, 2H), 1.87 (m, 2H), 0.91 (m, 9H), 0.07 (m, 6H).
35.iii. 4-[3-(tert-butyl-dimethyl-silanyloxy)-propyl]-6-methoxy-1,4-dihydro-pyrido[2,3-b]pyrazine-2,3-dione:
[0263] A solution of intermediate 35.ii (0.5 g), ethylpyruvate (0.37 mL) EtOH (12 mL) was
stirred at 50°C overnight. The mixture was concentrated under reduced pressure and
purified by CC (Hept/EA 9:1 to 2:1), affording the title compound as a dark grey solid
(222 mg, 38% yield).
MS (ESI, m/z): 364.1 [M+H
+].
35.iv. 4-(3-hydroxy-propyl)-6-methoxy-2-methyl-4H-pyrido[2,3-b]pyrazin-3-one:
[0264] Starting from intermediate 35.iii (218 mg) and using procedure F, the title compound
was obtained, after purification by CC (EA), as a black solid (152 mg; 100% yield).
MS (ESI, m/z): 250.1 [M+H
+].
35.v. 3-(6-methoxy-2-methyl-3-oxo-3H-pyrido[2,3-b]pyrazin-4-yl)-propionaldehyde:
[0265] A solution of intermediate 35.iv (149 mg) and DIPEA (0.6 mL) in DCM (4 mL) was cooled
to 0°C and treated with a solution of Pyr.SO
3 complex (7.6 g) in DMSO (29 mL).The reaction was further stirred at this temperature
for 2.5 h and quenched with water (200 mL). The org layer was separated and the aq.
layer was extracted with DCM. The combined org. layers were sequentially washed with
water, brine, dried over MgSO
4, filtered and concentrated under reduced pressure. The compound was used as such
in the following step.
MS (ESI, m/z): 248.3 [M+H
+].
35.vi. 6-methoxy-2-methyl-4-(3-{[(R)-2-oxo-3-(3-oxo-3,4-dihydro-2H-benzo[1,4]thiazin-6-yl)-oxazolidin-5-ylmethyl]-amino}-propyl)-4H-pyrido[2,3-b]pyrazin-3-one:
[0266] Starting from intermediate 35.v (74 mg) and intermediate B (83.8 mg) and using procedure
I, the title compound was obtained, after CC (EA, then DCM/MeOH 19:1 to 9: 1), as
a beige foam (34 mg; 22% yield).
1H NMR (DMSO d6) δ: 10.53 (m, 1H), 8.03 (d, J = 8.5 Hz, 1H), 7.29 (m, 2H), 7.09 (m,
1H), 6.78 (d, J = 8.8 Hz, 1H), 4.68 (m, 1H), 4.35 (m, 2H), 3.99 (m, 4H), 3.76 (m,
1H), 3.41 (s, 2H), 2.80 (m, 2H), 2.64 (m, 2H), 1.83 (m, 2H).
MS (ESI, m/z): 511.0 [M+H
+].
Pharmacological properties of the invention compounds
Experimental procedures:
Results:
[0268] All Example compounds were tested against several Gram positive and Gram negative
bacteria such as S.
aureus, E. faecalis, S. pneumoniae, M. catarrhalis, A. baumanii, E.coli or P. aeruginosa. Antibacterial test results against
Moraxella catarrhalis A894 are given in the table hereafter (MIC in mg/1).
| Compound of Example |
Moraxella catarrhalis A894 |
Compound of Example |
Moraxella catarrhalis A894 |
Compound of Example |
Moraxella catarrhalis A894 |
| 1 |
<=0.031 |
13 |
<=0.031 |
25 |
<=0.031 |
| 2 |
<=0.031 |
14 |
<=0.031 |
26 |
0.25 |
| 3 |
<=0.031 |
15 |
<=0.031 |
27 |
<=0.031 |
| 4 |
<=0.031 |
16 |
<=0.031 |
28 |
1 |
| 5 |
0.25 |
17 |
<=0.031 |
29 |
0.063 |
| 6 |
<=0.031 |
18 |
<=0.031 |
30 |
<=0.016 |
| 7 |
0.5 |
19 |
<=0.031 |
31 |
1 |
| 8 |
0.25 |
20 |
<=0.031 |
32 |
1 |
| 9 |
<=0.031 |
21 |
<=0.031 |
33 |
<=0.031 |
| 10 |
0.125 |
22 |
<=0.031 |
34 |
8 |
| 11 |
<=0.031 |
23 |
<=0.031 |
35 |
<=0.016 |
| 12 |
1 |
24 |
<=0.031 |
|
|