BACKGROUND OF THE INVENTION
[0001] The Invention provides methods and compositions comprising steroids or analogs, such
as analogs of androst-5-ene-3β,17β-diol ("AED") or 1,3,5(10)-estratriene-17α-ethynyl-3β,17β-diol
("EED") for use as agents to modulate the biological activity of the androgen receptor
("AR") or to treat androgen responsive or related conditions such as prostate cancer
and benign prostatic hypertrophy ("BPH").
[0002] Prostate cancer represents the most commonly diagnosed non-cutaneous malignancy in
aging males and is the second leading cause of cancer-related death In North American
men. Androgen ablation has been the cornerstone of treatment for advanced forms of
this disease, typically by a combination of surgical or medical antiandrogen therapy.
Antiandrogens that are commonly used include hydroxyflutamide (HF), cyproterone acetate
and bicalutamide (casodex). Androgen ablation treatments are used to reduce the level
of endogenous androgens. However, most androgen-dependent prostate cancer cases appear
to progress to androgen-independent malignancies. Limiting the availability of androgens
to regional or metastatic prostate cancers usually induces remission, but after some
time the cancer often becomes refractory to androgen ablation treatments. It has been
suggested that genetic changes of the AR gene may contribute to a short response to
anti-androgen therapy. However, the mechanisms responsible for conversion of prostate
cancer cells to an androgen Independent condition are not fully characterized.
[0003] BPH Is a disease that affects approximately 60% of males older than about 60 years
of age. An elevated accumulation of male hormones such as dihydrotestosterone ("DHT")
in prostate tissue may contribute to prostate enlargement The accumulation of DHT
appears to result from elevated intracellular DHT receptor levels. The increase is
associated with an elevation of estrogen levels relative to androgen levels, which
decrease with age. The urological symptoms consist In an elevated frequency of miction
due to elevated residual urine. This is typically accompanied by a weak flow of urine,
a time-delayed start of miction, and repeated infections of the bladder and kidneys.
BPH treatment includes surgery to remove the obstruction, but this is not always effective
or has unwanted side-efects, e.g., incontinence or decreased libido. Other treatments
such as androgen ablation by bilateral orchiectomy or androgen ablation chemotherapy
are too invasive or have unwanted side-effects. Less invasive methods exist, e.g.
balloon dilatation treatment with hyperthermia or microwaves, but they can have limited
efficacy.
[0004] Chemotherapy for conditions such as prostate cancer and BPH, or their smptoms, include
administering androgen synthesis inhibitors such as 5α reductase inhibitors to inhibit
production of sex hormones such as testosterone or dihydrotestosterone, or administering
Naftopidil for dysuria. Treatment with 5α reductase inhibitors has been combined with
other treatments such as antiestrogens, aromatase (estrogen synthetase) inhibitors,
inhibitors of 17β-hydroxysteroid dehydrogenase or lutenizing hormone releasing hormone
agonists or antagonists. Other proposed treatments include administering aromatase
inhibitors such as 4-hydroxyandrostene-3,17-dione. Chemotherapy typically has drawbacks.
It can have unwanted side effects, particularly in older patients or it can become
ineffective over time. Various treatments and their limitations have been described,
see, e.g.,
U.S. patents 4,059,630,
4,310,523,
4,659,695,
4,970,204,
5,137,882,
5,372,996,
5,494,914,
5,561,124,
5,593,981,
5,994,334,
5,994,335,
5,998,377,
6,015,808,
6,093,722,
8,110,906 and European publication
EP 0 401 653.
[0005] Biological properties of AED and related steroid compounds have been disclosed, see,
e.g.,
U.S. patent numbers 2833793,
2911418,
3148198,
3471480,
3710795,
3711606 3976691,
4268441,
4427649,
4542129,
4666898,
4898694,
4956355,
4978532,
5001119,
5043165,
5077284,
5028631,
5110810,
5157031,
5162198,
5175154,
5206008,
5277907,
5292730,
5296481,
5372996,
5387583,
5407684,
5424463,
5461042,
5478566,
5506223,
5518725,
5527788,
5527789,
5532230,
5559107,
5562910,
5583126,
5585371,
5587369,
5591736,
5593981,
5610150,
5635496,
5641768,
5641768,
5656621,
5660835,
5677366,
5686438,
5696106,
5700793,
5707983,
5709878,
5710143,
5714481,
5728688,
5736537,
5744462,
5753237,
5756482,
5776921,
5776923,
5780460,
5795880,
5798347,
5798348,
5804576,
5807848,
5807849,
5811418,
5824313,
5824668,
5824671,
5827841,
5837269,
5837700,
5843932,
5846963,
5856340,
5859000,
5869090,
5863910,
5872114,
5872147 and
5910407; German patent numbers
2035738 and
2705917;
PCT publication numbers WO 95/21617,
WO 97/48367,
WO 98/05338,
WO 98/50040,
WO 98/50041,
WO 98/58650; European publication number
0020029.
[0006] The androgen receptor and co-activators such as ARA
70, ARA
24, ARA
54, ARA
55 and Rb, and methods to use them have been described, e.g.,
U.S. patent 5789170,
5614620; international publication number
WO 00/04152.
[0007] The invention methods and compositions accomplish one or more of several objets.
Invention objects include providing methods and compositions to inhibit proliferation
of prostate cancer cella a subject. Other objects are to provide methods to make and
use compositions and formulations comprising EED analogs or othercompounds disclosed
herein. Additional objects will be apparent from the disclosure.
SUMMARY OF THE INVENTION
[0010] The invention further provides a compound having the structure
- (a

or
- (b

[0011] The inventive compound can be a powder or granules.
DETAILED DESCRIPTION OF THE INVENTION
[0013] As used herein and unless otherwise stated or implied by context, the following terms
have the meanings defined here.
[0014] Stereoisomers. The compounds according to the invention include enriched or resolved optical isomers
at any or all asymmetric atoms as are apparent from the depictions. Both racemic and
diasteromeric mixtures, as well as the individual optical isomers can be isolated
or synthesized so as to be substantially free of their enantiomeric or diastereomeric
partners.
[0015] One or more of the following methods are used to prepare the enantiomerically enriched
or pure isomers herein. The methods are listed In approximately their order of preference,
i.e., one ordinarily should employ stereospecific synthesis from chiral precursors
before chromatographic resolution or before before spontaneous crystallization.
[0016] Stereospecific synthesis is conveniently used when the appropriate chiral starting
material is available and reaction steps are chosen that do not result in undesired
racemization at chiral sites. One advantage of stereospecifc synthesis is that it
does not produce undesired enantiomers that must be removed from the final product,
thereby lowering overall syntheticyield. In general, those skilled in the art would
understand what starting materials and reaction conditions should be used to obtain
the desired enantiomerically enriched or pure isomers by stereospecific synthesis.
[0017] Another synthesis method of general utility is chromatographic resolution of enantiomers
on chiral chromatography resins. These resins are packed In columns, commonly called
Pirkle columns, and are commercially available. The columns contain a chiral stationary
phase. The racemate is placed in solution and loaded onto the column, and thereafter
separated by HPLC. See for example,
Proceedings Chromatographic Society - international Symposium on Chiral Separations,
Sept. 3-4,1987. Examples of chiral columns that could be used to screen for the optimal separation
technique would include Diacel Chriacel OD, Regis Pirkle Covalent D-phenylglycine,
Regis Pirkle Type 1A, Astec Cyclobond II, Astec Cyclobond III, Serva Chiral D-DL=Daltosil
100, Bakerbond DNBLeu, Sumipax OA-1000. Merck Cellulose Triacetate column, Astec Cyclobond
I-Beta, or Regis Pirkle Covalent D-Naphthylalanine. Not all of these columns are likely
to be effective with every racemic mixture. However, those skilled in the art understand
that a certain amount of routine screening may be required to identify the most effective
stationary phase. When using such columns it is desirable to employ embodiments of
the compounds of this invention in which the charges are not neutralized, e.g., where
acidic functionalities such as carboxyl are not esterifled or amidated.
[0018] Another method entalis converting the enantiomers In the mixture to diasteriomers
with chiral auxillaries and then separating the conjugates by ordinary column chromatography.
This is a very suitable method, particularty when the embodiment contains free carboxyl,
amino or hydroxyl that will form a salt or covalent bond to a chiral auxiliary. Chirally
pure amino acids, organic acids or organosulfonic acids are all worthwhile exploring
as chiral auxiliaries, all of which are well known In the art Salts with such auxiliaries
can be formed, or they can be covalently (but reversibly) bonded to the functional
group. For example, pure D or L amino acids can be used to amidate the carboxyl group
of invention embodiments that comprise a carboxyl group and then separated by chromatography.
[0019] Enzymatic resolution Is another method of potential value. In such methods one prepares
covalent derivatives of the enantiomers in the racemic mixture, generally lower alkyl
esters (for example of carboxyl), and then exposes the derivative to enzymatic cleavage,
generally hydrolysis. For this method to be successful an enzyme must be chosen that
is capable of stereospecific cleavage, so it is frequently necessary to routinely
screen several enzymes. If esters are to be cleaved, then one selects a group of esterases,
phosphatases, and lipases and determines their activity on the derivative. Typical
esterases are from liver, pancreas or other animal organs, and include porcine liver
esterase.
[0020] If the enantiomeric mixtures separates from solution or a melt as a conglomerate,
i.e., a mixture of enantiomerically-pure crystals, then the crystals can be mechanically
separated, thereby producing the enantiomerically enriched preparation. This method,
however, is not practical for large scale preparations and is of limited value for
true racemic compounds.
[0021] Asymmetric synthesis is another technique for achieving enantiomeric enrichment.
For example, a chiral protecting group is reacted with the group to be protected and
the reaction mixture allowed to equilibrate. If the reaction is enantiomerically specific
then the product will be enriched in that enantiomer.
[0022] Further guidance in the separation of enantiomeric mixtures can be found, by way
of example and not limitation, in "
Enantiomers, Racemates, and resolutions", Jean Jacques, Andre Collet, and Samuel H.
Wilen (Krieger Publishing Company, Malabar, FL, 1991, ISBN 0-89464-618-4): Part 2, Resolution of Enantiomer Mixture, pages 217-435; more particularly, section
4, Resolution by Direct Crystallization, pages 217-251, section 5, Formation and Separation
of Diastereomers, pages 251-369, section 6, Crystallization-induced Asymmetric Transformations,
pages 369-378, and section 7, Experimental Aspects and Art of Resolutions, pages 378-435;
still more particularly, section 5.1.4, Resolution of Alcohols, Transformation of
Alcohols into Salt-Forming Derivatives, pages 263-266, section 5.2.3, Covalent Derivatives
of Alcohols, Thiols, and Phenols, pages 332-335, section 5.1.1, Resolution of Acids,
pages 257-259, section 5.1.2, Resolution of Bases, pages 259-260, section 5.1.3, Resolution
of Amino Acids, page 261-263, section 5.2.1, Covalent Derivatives of Acids, page 329,
section 5.2.2, Covalent derivatives of Amines, pages 330-331, section 5.2.4, Covalent
Derivatives of Aldehydes, Ketones, and Sulfoxides, pages 335-339, and section 5.2.7,
Chromatographic Behavior of Covalent Diastereomers, pages 348-354.
[0023] The compounds according to the invention are useful to treat conditions that are
associated with or that respond to modulation of AR activity, including prostate cancer,
acne, male pattern baldness, hirsutism, hypogonadism and breast cancer. These compounds
may be optionally be used in combination therapies to treat any of these diseases
or conditions. The combinations include compound(s) according to the invention combined
with surgery, radiation therapy, cytotoxic agents, cytostatic agents or hormone therapies,
including any of the therapies or treatments disclosed herein or in any of the references
cited herein.
[0024] The compounds according to the invention are also useful to determine if the AR or
another steroid receptor, e.g., an orphan receptor, are present in a cell population
or cell extract. In these applications, the compounds will typically be labeled, e.g.,
radiolabels (
14C,
3H,
32P,
35S or a radioactive iodine isotope) or labeled with a crosslinking molety. In related
applications, the compounds are useful as reference standards to compare their capacity
to modulate AR activity with the capacity of known AR modulators, such as AED. In
these applications, a compound according to the invention is used in a suitable assay
system, e.g., one that comprises cells (
in vitro or
in vivo) that contain functional AR, an AR-responsive gene, e.g., ornithine carboxylase,
that can be conveniently assayed, a compound according to the invention and a test
compound. In such methods, the effect of the compound according to the invention on
the capacity of the test compound to modulate the AR is examined, usually using a
suitably controlled system, e.g., with varying concentrations of the compound according
to the invention or varying concentrations of the test compound. Assay systems, or
components thereof that comprise the Ar have been described, see, e.g.,
U.S. patents 4981784 and
5071773,
Evans, et al., Science 240:889-895 1988,
T. Berger et al., J. Steriod Biochem. Molec. Biol. 41:773-778 1992,
J. Simenthal, et al., J. Biol. Chem. 266:510-514 1991,
G. Scalabrino et al., Mol. Cell. Endocrinol. 77:1-35 1991,
O. Janne, et al., Ann. N. Y. Acad. Sd. 438:72-841984, and
R. Djurtluus, Anal. Biochem. 113:352-355 1981.
[0025] An effective dose of a compound according to the invention or the "active ingredient",
for use in therapeutic applications, e.g., prostate cancer treatment, will depend
to a certain extent at least on factors such as the status of the condition being
treated, whether the compound(s) is being used prophylactically (lower doses) or the
severity of the malignancy, the method of delivery, and the pharmaceutical formulation.
These factors will be determined by the clinician using conventional dose escalation
studies. Typically the dose administered to the subject will be from about 0.03 to
about 30 mg/kg body weight per day, generally about 0.1 to about 10 mg/kg body weight
per day. For example, for topical delivery the daily candidate dose for an adult human
of approximately 70 kg body weight will range from about 1 mg to about 750 mg, generally
between about 5 mg and about 300 mg, usually between about 30 mg and about 250 mg.
A dally dose may take the form of single or multiple doses or administration sites.
For a formula 1 or 2 compound that is delivered parenterally, e.g., i.v., s.c. or
i.m., the dose will generally be lower (e.g., about 0.02 to about 6 mg/kg) than a
dose administered orally.
[0026] Pharmaceutical formulations that comprise a compound according to the invention will
typically comprise one or more carriers or excipients and optionally other therapeutic
ingredients. The carrier(s) will generally be "acceptable" in the sense of being compatible
with the other ingredients of the formulation and physiologically Innocuous to the
recipient thereof. Such carriers or excipients are known, e.g., fillers, lubricants,
binders and various liquid excipients for liquid formulations. Suitable carriers include
those disclosed In the references cited herein.
[0027] Suitable formulations include aqueous or oily solutions of the active ingredient.
Formulations suitable for parenteral delivery of the active ingredient include aqueous
and non-aqueous compositions where the active ingredient is dissolved or suspended
in solution. Such formulations will typically comprise about 25-300 mg/mL of the active
ingredient, usually about 40-200 mg/mL Formulations suitable for parenteral administration
include aqueous and non-aqueous sterile injection solutions which may contain anti-oxidants,
buffers, bacteriostats or solutes that render the formulation isotonic with the blood
of the intended recipient. Other parenteral formulations may comprise aqueous and
non-aqueous sterile suspensions which may include suspending agents and thickening
agents.
[0028] Formulations suitable for topical administration Include creams or ointments wherein
the formula 1 or 2 compound is dissolved orsuspended in a suitable carrier, especially
anon-aqueous solvent or carrier for the active ingredient. The active ingredient is
typically present in such formulations in a concentration of 0.5 to 20% w/w, often
0.5 to 10% w/w. Such formulations are suitable for use in applications such as treating
male pattern baldness or acne.
[0029] Formulations suitable for buccal or sublingual administration include lozenges comprising
the active ingredient, which is optionally present in a flavored basis such as sucrose
and acacia or tregacanth. Pastilles may comprise the active ingredient in an inert
basis such as gelatin and glycerin, or sucrose and acacia, and mouthwashes may comprise
the active ingredient In a suitable liquid carrier.
[0030] Formulations for rectal administration may be presented as a suppository with a suitable
base comprising for example cocoa butter or a salicylate.
[0031] Formulations suitable for intrapulmonary or nasal administration will have a particle
size for example in the range of 0.01 to 200 microns (including particle sizes in
a range between 0.01 and 500 microns in increments of 0.1 microns such as 0.1, 0.2,
0.3, 0.4, 0.5, 1, 2, 5, 30 microns, 35 microns, etc.), which is administered by inhalation
through the nasal passage or by inhalation through the mouth so as to reach the various
bronchi or alveolar sacs. Formulations suitable for aerosol or dry powder administration
may be prepared according to conventional methods and may be delivered with other
therapeutic agents such as compounds heretofore used in the treatment or prophylaxis
of prostate cancer.
[0032] Formulations suitable for vaginal administration may be presented as pessaries, tampons,
creams, gels, pastes, foams or spray formulations containing In addition to the active
ingredient such carriers as are known in the art to be appropriate.
[0033] Formulations comprising an active ingredient are presented in unit-dose or multi-dose
containers, for example sealed ampoules and vials, and may be stored In a freeze-dried
(lyophilized) condition requiring only the addition of the sterile liquid carrier,
for example water for injection, immediately prior to use. Extemporaneous injection
solutions and suspensions are prepared from sterile powders, granules and tablets
of the kind previously described. Preferred unit dosage formulations are those containing
a daily dose or unit daily sub-dose, as described herein, or an appropriate fraction
thereof, of the active ingredient
[0034] It should be understood that in addition to the ingredients particularly mentioned
above the formulations of this invention may include other agents conventional in
the art having regard to the type of formulation In question, for example those suitable
for oral administration may include flavoring or coloring agents.
[0035] The Invention further provides veterinary compositions comprising at least one active
ingredient together with a veterinary carrier therefor.
[0036] Veterinary carriers are materials useful for the purpose of administering the composition
and may be solid, liquid or gaseous materials which are otherwise inert or acceptable
in the veterinary art and are compatible with the active ingredient. These veterinary
compositions may be administered orally, parenterally or by any other desired route.
[0037] The active ingredeints may be used to provide controlled release pharmaceutical formulations
containing an active ingredient (controlled release formulations') in which the release
of the active ingredient is controlled and regulated to allow less frequency dosing
or to improve the phamacokineticor toxicity profile of a given active ingredient
[0038] The formulations include those suitable for any of the foregoing administration routes.
The formulations may conveniently be presented in unit dosage form and may be prepared
by any of the methods well known in the art of pharmacy. Techniques and formulations
generally are found in Remington's Pharmaceutical Sciences (Mack Publishing Co., Easton,
Pa.). Such methods include the step of bringing into association the active ingredient
with the carrier which constitutes one or more accessory ingredients or excipients.
In general, the formulations are prepared by uniformly and intimately bringing into
association the active ingredient with liquid carriers or finely divided solid carriers
or both, and then, if necessary, shaping the product.
[0039] Formulations of the invention suitable for oral administration are prepared as discrete
units such as capsules, cachets or tablets each containing a predetermined amount
of the active ingredient; as a powder or granules; as solution or a suspension in
an aqueous liquid or a non-aqueous liquid; or as an oil-in-water liquid emulsion or
a water-in-oilliquid emulsion. The active ingredient may also be presented as a bolus,
electuary or paste.
[0040] A tablet is made by compression or molding, optionally with one or more accessory
ingredients. Compressed tablets may be prepared by compressing in a suitable machine
the active ingredient in a free-flowing form such as a powder or granules, optionally
mixed with a binder, lubricant, inert diluent, preservative, surface active or dispersing
agent Molded tablets may be made by molding in a suitable machine a mixture of the
powdered active ingredient moistened with an inert liquid diluent The tablets may
optionally be coated or scored and optionally are formulated so as to provide slow
or controlled release of the active ingredient therefrom.
[0041] If desired, the aqueous phase of a cream base may include, for example, polyhydric
alcohol, i.e. an alcohol having two ormore hydroxyl groups such as propylene glycol,
butane 1,3-diol, mannitol, sorbitol, glycerol and polyethylene glycol and mixtures
thereof. The topical formulations may desirably include a compound which enhances
absorption or penetration of the active ingredient through the skin or other affected
areas. Examples of such dermal penetration enhancers include dimethyl sulphoxide and
related analogs.
[0042] The oily phase of the emulsions of this invention may be constituted from known ingredients
in a known manner. While the phase may comprise merely an emulsifier (otherwise known
as an emulgent), it desirably comprises a mixture of at least one emulsifler with
a fat or an oil or with both a fat and an oli
. Preferably, a hydrophilic emulsifier is included together with a lipophilic emulsifler
which acts as a stabilizer. It is also preferred to include both an oil and a fat
Together, the emulsifier(s) with or without stabilizer(s) make up the so-called emulsifying
wax, and the wax together with the oil and tat make up the so-called emulsifying ointment
base which forms the oily dispersed phase of the cream formulations.
[0043] Emulgents and emulsion stabilizers suitable for use in the formulation of the invention
include Tween.RTM. 60, Span.RTM. 80, cetostearyl alcohol, benzyl alcohol, myristyl
alcohol, glyceryl mono-stearate and sodium lauryl sulfate.
[0044] The choice of suitable oils or fats for the formulation is based on achieving the
desired cosmetic properties. The cream should preferably be a non-greasy, non-staining
and washable product with suitable consistency to avoid leakage from tubes or other
containers. Straight or branched chain, mono- or dibasic alkyl esters such as di-isoadipate,
isocetyl stearate, propylene glycol diester of coconut fatty acids, isopropyl myristate,
decyl oleate, isopropyl palmitate. butyl stearate, 2-ethylhexyl palmitate or a blend
of branched chain esters known as Crodamol CAP may be used, the last three being preferred
esters. These may be used alone or in combination depending on the properties required.
Alternatively high melting point lipids such as white soft paraffin and/or liquid
paraffin or other mineral oils are used.
[0045] Exemplary synthesis methods. By way of exemplification and not limitation,the following methods are used to prepare
the one or more of the compounds disclosed herein. Starting materials or straightforward
variations of the schemes are found, e.g., in the following citations
US patents 4602008,
4989694,
5001119,
5175154,
5571795,
5627270,
5681984,
5714481,
5744453,
5939545,
5939570,
5962442,
5962443.
5994568; international publication numbers
WO 9408588,
WO 9508558,
WO 9508559,
WO 9638466,
WO 9809450: and European patent applications
EP 232788,
EP 430078.
[0046] Scheme 1. Principles for synthesis of compounds according to the invention are shown in the
schemes below. When R
24 and R
25 are both -CH
3 in the β-configuration, H at the 9 and 14 positions are in the α-configuration, acetate
at the 3-position is in the β-configuration. and H at the 8 position is in the β-configuration,
the first compound in scheme 1 is DHEA acetate. The acetate groups at the 3, 7, 16,
17 or other positions in this scheme and in other schemes disclosed herein may independently
be other ester moieties as described herein, e.g., C
2-50 esters including -C(OKCH
2)
0-4-(CF
2)
0-4-CF
3' including -C(O)-CF
3,-C (O)-C
2-29 optionally substituted alkyt, -C(O)-CH
2-C
2-28 optionally substituted alkenyl,
-C(O)CH
2-C
2-28 optionally substituted alkynyl, -C(OKCH
2)
0-6 substituted phenyl, or -C(O)-(CH
2)
0-6-optionnaly substituted heterocycle or other organic moieties as disclosed herein or
in the cited references.
[0047] Typical substituents for these organic moieties are as described herein, e.g., one,
two, three or more independently selected -O-, =O, optionally protected hydroxyl,
-S-, optionally protected thiol, -NH-, optionally protected -NH
2, optionally protected -C(O)OH, -C(O)-NH-, -C(O)-NH
2, -NH
2-C(O)-H,-NH
2-C(O)C
0-4H
1.9,-NH
2-C(O)O-C
0-4H
1.9,-CN, -NO
2, -N
3 or halogen. Reactive groups are protected as needed, e.g., =O would usually be protected
in the LiCR reaction that is used to generate compound
1 in scheme 1 below.
Scheme 2. Compounds of formula
2A are prepared from structure
A compounds shown In scheme 1 using the last two steps of Scheme 1: (1) dibromantin,
(2) UBr, (3) LI-C-R,where R is CR
A and R
A is -H or -C
1-12 optionally substituted alkyl. When H at the 9 and 14 positions are In the α-configuration
and H at the 8 position Is In the β-configuration the first compound In scheme 1 is
DHEA acetate. Typical substituents for the R
A alkyl moiety includes one, two or more independently selected -O-, optionally protected
=O, optionally protected hydroxyl,- S-, optionally protected thiol, -NH-, optionally
protected -NH
2, optionally protected . C(O)OH, -C(O)-NH-, -C(O)-NH
2, -NH
2-C (O)-H, -NH
2-C(O)-C
0-4H
1-8,-NH
2-C(O)O-C
0-4H
1.9 -CN, -NO
2, -N
3 or halogen.
Scheme 3. The allylic bromination at C-7 is accomplished essentially as shown in Scheme 1.
R and R
A are as defined in Schemes 1 and 2.
Scheme 4. The addition of lithium reagent (lithium acetylide when R is-CH) to the 17-position
>C=O
in the presence of the bromide at C-16 results in epoxide formation or in a pinacol
rearrangement Alternatively, compounds without of structure 3 can be dehydrated by
mild acid catalysis to form compounds of formula
4 by treatment of the alkene with Br
2, H
2O. R and R
A are as defined in Schemes 1 and 2.
Scheme 5. Sodium borohydride gives a mixture of epimers at C-7, which may be separated by standard
methods, e.g., HPLC, TLC or column chromatography. To obtain the pure 7α-OH compound,
allylic bromination followed by hydrolysis is accomplished, e.g., essentially as described
in Schemes 1 and 3.
Scheme 6. Formula
6 compounds are prepared by treatment of the acetate with lithium acetylide as in Schemes
1, 2, 3 or 4. R and R
A are as defined in Schemes 1 and 2.
Scheme 7. Formula
7 compounds are prepared from the 3-acetate with reagents described In Schemes 1 and
4. R and R
A are as defined in Schemes 1 and 2.
Scheme 8. Formula 8 compounds are prepared from the formula
A compounds by sodium borohydride reduction at C-17 followed by acetylation.
Scheme 9. The starting material is made using reactions described in Schemes 1 and 3.
Scheme 10. Reduction and acetylation at C-3 and hydrolysis and oxidation at C-17 will allow
formula 10a and 10b compounds to undergo functionalization as shown in Schemes 1-9
at C-3. C-16 and C-17. The 7-oxo acetate can be substituted for the formula
A compound 3-acetate and functionalization at C-3, C-18 and C-17 is achieved similarly
for 7-oxo compounds using the reactions shown in schemes 1-9.
Treatment of
10a with LDA, followed by alkylation of the enolate allows introduction of side chains,
which may be, e.g., C1-C20 alkyl (methyl, ethyl), C1-C20 alkenyl (CH
2=CH-(CH
2)
0-6-), benzyl, -(CH
2)
1-4-O(CH
2)
0-4CH
3.

Schemes 1-9 show the introduction of the hydroxyl function at the positions shown.
Methods to convert hydroxyl to other functional groups are accomplished essentially
as described, e.g., in the references cited herein. For example, esters, of formula
1 -
10c compounds, such as -O-C(O)R
8 where R
8 is a C
1-50 organic moiety, are prepared from the steroid alcohol by treatment with the appropriate
acid anhydride or acid chloride (R
8-C(O)-Cl) to form any desired ester. Ethers, such as -O-R
8, are prepared from alcohols by formation of the alkaline metal alkoxide (Na
+ or K
+) followed by treatment with a primary or secondary iodide (R
8-I). Thionoesters, R
8-C(S)-O-, are prepared by treating the R
8-C(O)-O- ester with Lawesson's reagent.
Sulfates, NaO-S(O)(O)-O-, R
8-O-S(O)(O)-O-, e.g., CH
3(CH
2)
0.
18-S(O)(O)-O-. are prepared by treatment of alcohols with chlorosulfonic acid followed
by NaOH or alternatively by oxidation of sulfites using KMnO
4. If the alkyl (e.g., methyl) ester is desired alkylchloro-sulfonate (methylchloro-sulfonate)
can be used. Sulfites HO-S(O)-O- and ammonium salts NH
4 O-S(O)-O, or R
8 O-S(O)-O- esters (e.g., CH
3 O-S(O)-O-) are prepared by standard methods. The ammonium salts are prepared by treatment
of alcohols with ammonia and sulfur dioxide. The esters such as alkyl, alkenyl and
alkynyl esters (e.g., methyl ester) are obtained when alcohols are treated with alkylchlorosulfite
(e.g., methycholorosulfite), alkanylchlorosulfite or alkynylchlorosulfite in the presence
of a suitable base such as triethylamine. Phosphoesters, R
8O-P(OR
PRO)-O-are prepared by treating the alcohol with diethylchlorophosphate In the presence
of Na
2CO
3. Alternatively, if the alcohol is treated with phosphoric acid diesters in the presence
of triphenylphospine (PPh
3) and diethylazodicaboxylate (DEAD) the corresponding triesters are formed with inversion
(Mitsunobu reaction).
Phosphothloesters, R
8O-P(SR
PR)(O)-O- are generated by treatment of alcohols with the monothio analog of diethylchlorophosphate
as described for phosphoesters yielding the phosphothioesters. Carbonates, R
8O-C(O)-O-are generated from the corresponding steroid alcohol using the chloroformate
(R
8-C(O)-Cl), e.g., C
1-20 alkyl, alkenyl or alkynyl chloroformates (e.g. CH
3(CH
2)
0-5-C(O)Cl). Carbamates, R
8-NH-C(O)-O- are made from steroid alcohols by treatment with isocyanates (R
8N-C=O) or NaOCN in the presence of trifluroroacetic acid. Aminoacid esters, ZNX-CHY-C(O)-O-
are generated by coupling the steroid alcohol with the acid chloride of the N-protected
amino acid. Oxidation of hydroxyl groups that are linked to the steroid nucleus is
used to obtain ketones and related functionalities. For example, conversion of alcohols
to ketones can be achieved using a variety of oxidizing agents such as CrO
3 in AcOH, or pyridinium cholorchromate, pyridinium dichromate or oxalyl chloride with
triethylamine (Swem oxidation). Thioketones (=S) are prepared by treating ketones
with Lawesson's reagent (2,4-bis(4-methoxyphenyl)-1,3,2,4-dithladiphosphetane-2,4-disulfide;
commercially available from Aldrich). Thioacetals, -C(SR
8)(SR
8)-, are prepared from ketones (-C(O)-) by treatment with R
8-SH thiols under acid catalysis conditions (e.g., HCl). Phosphonoesters, RO-P(OR
PR)(O)-, are generated by addition of the phosphorus acid diester to ketones in the
presence of KF to yield hydroxy phosphonoesters. One may optionally remove the hydroxy
group using a dehydration and hydrogenation sequence.
Substitution of hydroxyl groups is used to generate a number of functionalities. For
example, thiols, -SH, are prepared from alcohols by conversion of the alcohol with
inversion to the bromide using PBr
3. Treatment of the bromide with thiourea followed by NaOH gives the thiol. Thioethers,
R
8-S-,
are prepared from thiols by treatment with NaOH and the required halide, e.g., alkyl
halide. Alternatively, alcohol derivatives like tosylates or mesylates can be displaced
by thiolate anions, R
8-S
-, to yield the thloether. Thioesters, R-C(O)-S-, are prepared by treating the tosylate
(mesylate) of the alcohol with the sodium salt of the thioacid.
Substitution of hydroxy groups can be used to generate both esters, R
8O-C(O)-, and amides. NHR
8-C(O)-, linked to the steroid at carbon atoms. For amides and amines, R
8 is -H, a protecting group or a C
1-50 organic moiety. These are synthesized from the steroid bromide with inversion by
displacement with NaCN. The cyanide group can be hydrolyzed to the amide or the acid.
The acid is esterified or treated by standard peptide coupling reactions with an O-protected
amino acid in the presence of a suitable carboxyl activating agents such as dicyclohexylcarbodiimide
(DCC) to form steroid -C(O)-NH-CHY-C(O)-OR, where Y is the side chain of an amino
acid or a C1-C10 organic moiety and R is a protecting group (or hydrogen when deprotected).
Amines and derivatives of amines, e.g., R
8NH-, R
8-C(O)NH-, R
8OC(O)-NH- or R
8O-C(O)-CHR
8-NH- linked to steroid carbon atoms, are typically prepared by standard methods. For
example, amines (NH
2-steroid) are generally prepared using the Hoffmann rearrangement (Br
2, NaOH) from the amide (NH
2-C(O)-steroid) or the Curtius rearrangement (NaN
3) from the acid chloride of the steroid. The R
8 substituent can subsequently be introduced by alkylation. Steroid alcohols can be
used as starting materials under standard Mitsunobu conditions (PPh
3, DEAD) to yield N-Boc sulfonamides using N-(t-butoxycarbonyl)-p-toluenesulfonamide.
One can selectively remove either protecting group. Treatment with trifluoroacetic
acid affords the sulfonamide (R
8-S(O)(O)-NH-steroid). Alternatively, sodium napthalenide deprotects to give the N-Boc
compound. Amines (NH
2-steroid) can be converted to amides (R
8NH-C(O)-steroid) using acyl chlorides (R
8-C(O)-Cl). Treatment with ethyl chloroformate gives the N-carbamate (R
8O-C(O)-NH-steroid). The amine (NH
2-steroid) can be alkylated with an α-bromoester (R
8-C(O)-CHY-NH
2) to yield the amio acid substituted steroid (R
8-O-C(O)-CHY-NH-steroid).
Where reactions such as substitutions give a product mixture, the desired intermediate
is optionally separated from other products or at least partially enriched (e.g.,
enriched at least about 10-fold, usually at least about 50-1 00-fold) from other products
before subsequent reactions are conducted. Substitution at steroid carbon atoms will
generally proceed with greatest efficiency at the 3-position, which is relatively
sterically unhindered and C-17 is generally somewhat less accessible than the C-3
position. The relative reactivities of the C-3, C-7, C-17 and C-16 positions allows
one to use their reactivities to control the sequential introduction of different
functional groups into the same steroid molecule. Also, groups, such as hydroxyl at
more reactive positions, C-3 or C-17, may be sequentially protected or deprotected
to allow introduction of functional groups at other positions, such as C-7 or C-16.
Polymers such as PEG are linked to the compounds essentially as described above. For
example, PEG 200 or PEG 300 is linked to the steroid at the 3, 7, 16, 17 or other
positions by an ether linkage (PEG-O-steroid) using a PEG alkoxide (PEG-ONa), to displace
the steroid bromide. Alternatively, PEG-Br can be treated with the steroid alkoxide.
Polyethylene glycol esters such as those described in
U.S. patent 5681 964 can also be prepared using a suitable formula 1 compound and the methods described
therein. Monosaccharides or polysaccharides and oligonucleotides are linked to steroid
hydroxyl groups using known methods, see e.g.,
U.S. patent 5627270.
Scheme 11. Formula 1 or 2 compounds that contain an an organic moiety that is linked to the
1 position are prepared essentially as follows. The allylic bromination reaction to
generate
11 may utilize any suitable reagent, e.g., N-bromosuccinimide ('NBS') to yield the 1-bromo
derivative. This intermediate is treated with zinc to yield the alkylated derivative
12. Organic moieties are introduced into the 1 position using a corresponding reagent,
e.g., (R
35)
2CuLi, where R
35 is a C1-C25 organic moiety that may comprise 1, 2, 3, 4 or more substituents, e.g.,
-O-. -S-, -NH-, -OR
PR. protected ketone (e.g., ethylene ketal),
-SR
PR or -N(R
PR)
2- In other embodiments, R
35 is R
1. Thus, when R
35 is methyl, a methyl group is introduced into the 1 position, or when R
35 is -CH2-OR
PR, the -CH
2-OR
PR group is introduced into the 1 position. Compound
12 is converted to the 17 hydroxyl derivative
13 by hydrolysis using standard methods, e.g., treatment with sodium carbonate in ethanol
The compound
15 is converted to the 17-hydroxy derivative by reduction of the ketone, e.g., using UBH
4 or NaBH
4, in ethanol or by catalytic hydrogenation with H
2/Ni, H
2/Pt or H
2/Pd. Catalytic hydrogenation will also result in reduction of the double bond in
12, 13, 14 or
15. Alternatively, a hydroxyl at both the 3 and 17 positions is obtained by reducing
the ketone in compound
12 and removing the acetate group or by directly reducing the 3 ketone in compound
13.
Scheme 12. Formula 1 or 2 compounds that contain a hydroxyl or ether that Is linked to the 1
position are prepared essentially as follows. A hydroxyl is introduced into the 1
position by oxidation of a suitable starting material using alkaline hydrogen peroxide
to obtain the epoxide
16. The compound 16 is converted to the 1-hydroxyl derivative by treatment, e.g., with
excess lithium metal and excess ammonium chloride in NH
4-THF (1:1) at reflux to give
17. The ketal group is hydrolyzed to give the 17 ketone. The hydroxyl group at 1 is
optionally further converted to other moleties essentially as described above.
Scheme 13. Formula 1 or 2 compounds that contain an an organic moiety that is linked to the 2 position
are prepared essentially as follows. Organic moieties are introduced Into the 2 position
using a corresponding reagent, e.g., (R
35)
2CuLi, where R
38 is a C1-C25 organic moiety that may comprise 1, 2, 3, 4 or more substituents, e.g.,
-O-, -S-, -NH-, -OR
PR, protected ketone (e.g., ethylene ketal), -SR
PR or -N(R
PR)
2. In other embodiments, R
38 is R
3. Thus, when R
38 is methyl, a methyl group is introduced into the 2 position, or when R
38 is -CH
2-OR
PR, the -CH
2-OR
PR group is Introduced Into the 2 position. The starting material
18 is testosterone when R
24 and R
25 are both methyl. The compound 18 is alkyleted using an alkylating agent such as the
iodide R
36I in the presence of a strong base such as lithium diisopropylamide ("LDA"), n-butyllithium
sodium
t-pentoxide or (C
2H
5)
2Ni to give R
38 bonded to the steroid in the a and β configurations. The 2β-R
36 group is epimerized to the 2a configuration using a strong base, e.g., a sodium alkoxide
such as sodium methoxide in an alcohol such as methanol Alternatively the two epimers
are at least substantially separated by routine methods.

[0048] Other formula 1 and 2 compounds are prepared using methods similar to e.g., those
described herein or in the cited references.
[0049] The following reference examples further illustrate the invention
[0050] Reference example 1. AR activity assay. One biological function of the AR Is to act
as a transcription factor, which can modulate transcription of target genes. AED,
5α-dihydrotestosterone (DHT), 17β-estradiol (E2), and progesterone were purchased
from Sigma. Ethynyl derivatized steroids were purchased from Steraloids. The plasmid
pSG5-wild-type AR (pSG5) and mouse mammalian tumor virus (MMTV) -chloramphenicol acetyltransterase
(CAT) were constructed as described (6). The numbers in parentheses, e.g., (8) in
the preceding sentence, refer to the references listed in the reference section below.
Other steroid compounds, were synthesized using routine protocols and others have
been described (19, 20). The human prostate cancer cell line, PC-3, and human breast
cancer cell line, MCF-7, were maintained in Dulbecco's modified eagles medium (DMEM)
containing 10% fetal calf serum. DNA transfection and CAT assays were performed essentially
as described (4, 6, 7). Briefly, 4 x 10
5 cells were plated on 60 mm dishes 24 h before transfection, and the medium was changed
to DMEM (without phenol red) with 10% charcoal-stripped fetal calf serum 1 hour before
transfection. The cells were transfected using the calcium phosphate precipitation
method. The total amount of DNA was adjusted to 8.5 µg with pSG5 in each transfection
assay. After transfecting the cells for 24 hours, the transfection medium was removed,
fresh DMEM was added and steroids were added. The cells were then Incubated in DMEM
with steroids for 24 hours. After incubation, the cells were harvested and whole cell
extracts were used for CAT assay. Transfection efficiency was normalized by cotransfection
with a β-galactosidase vector, which acted as an Internal control. The CAT enzyme
activity was quantitated by phosphor Imager according to the manufacturer's instructions
(Molecular Dynamics).
| reference compound number |
reference compound name |
| 0 |
7-oxo-dehydroepiendrosterone |
| 1 |
17α-ethynyl-17β-hydroxy-4-estrene-3-one |
| 2 |
17α-ethynyl-17β-hydroxy-4-estrene-3-one |
| 3 |
17α-ethynyl-17β-hydroxy-5(10)-estrene-3-one |
| 4 |
1, 3, 5(10)-estratriene-17α-ethynyl-3β,17β-diol |
| 5 |
androst-5-one-3β,11β,17β-triol |
| 6 |
17α-ethynyl-androst-5-ene-3β,17β-diol |
| 7 |
17α-ethynyl-17β-hydroxy-4-androsten-3-one |
| 8 |
3β,17β-dihydroxy-androst-5-en-16-one |
| 9 |
3β,17β-dihydroxy-androst-4-en |
| 10 |
3β,-methylcarbonate-androst-5-en-7,17-dione |
| 11 |
3β,17β-dihydroxy-androst-5-en-11-one |
| 13 |
3β,17β-diacetoxy-androst-5-ene-7α, 17β-diol |
| 14 |
3β,17β-diacetoxy-androst-5-ene-7-one |
| 15 |
3β-methoxy-17β-hydroxy-androst-5-ene-7-one |
| 16 |
3β-methoxy-androst-5-ene-?, 17β-diol |
| 17 |
17β-mothoxy-androst-3,5-diene-7-one |
| 18 |
17-methyl-marrienolic acid |
| 19 |
17β-hydroxy-androst-3,5-diene-7-one |
| 21 |
5α-androstane-3α, 17β-diol |
| 22 |
7-oxo-androstene-3β, 17β-diol |

[0051] Example 2. Induction of AR-mediated transcriptional activity. Steroid compounds were
screened for their ability to induce AR transcriptional activity in the AR-negative
PC-3 cell line. The results of the CAT assay were obtained by transient co-transfection
of AR plasmid and a reporter plasmid (MMTVCAT) containing the CAT gene linked to the
androgen response element (ARE). After transfection, the cells were treated with various
DHEA derivatives at 1000, 10, and 0. 1 nM. As shown in figure 1 reference compounds
0, 4, 5, 6, 8, 10, 13, 15, 16, 18, and 22 had little androgenic activity but they
did induce a low level of AR-mediated CAT gene transactivation. AED (reference compound
21) had about the same capacity as DHT to stimulate AR-mediated CAT gene transcription.
[0052] Example 3. Identification of anti-adiol activity of steroids with low androgenic
effects. Several compounds were screened for their capacity to modulate AED's effects
on AR-mediated activation of gene transcription in PC-3 cells. The chemical structures
of reference compounds 4, 6, 8 and 10 are shown in figure 2A. The PC-3 cells were
co-transfected with pSG5 and the MMTV-CAT reporter vector in the presence of 50 nM
AED and each reference compound at a concentration of 10, 100, or 1000 nM. As shown
in figure 2B, reference compounds 4, 6, 8 and 10 antagonized AED-mediated AB transcriptional
activity. At concentrations of 0.1 µM and 1 µM, reference compounds 4 and 6 suppressed
the AED-induced AR transactivation to less than 30%. Reference compounds 0, 5, 13,
15, 18 an 22 show either activation of AED-mediated AR transcriptional activity or
they have no effect.
[0053] Example 4. Identification of anti-DHT effects of steroids. Reference compounds 4,
6, 8 and 10 were examined to determine whether these AED antagonists had the ability
to repress DHT-induced AR transactivation. PC-3 cells were co-transfected with pSG5
and the MMTV-CAT reporter plasmid in the presence of 1 nM DHT and each reference compound
at 10, 100, or 1000 nM. Reference compound 4 repressed the DHT-induced AR transactivation
to less than 40% at 1 µM (figure 3).
[0054] Example 5. Suppression of the AED-induced AR transcriptional activity in the presence
of HF. To mimic the in vivo condition of total androgen blockage in prostate cancer
patients, compounds 4, 6, 8 and 10 were examined for their capacity to antagonize
AED-induced AR transactivation in the presence of HF. In the presence of 1 µM HF,
50 nM AED, and each compound at 0.01, 0.1 or 1 µM, PC-3 cells were transiently transfected
with pSG5 and the MMTV-CAT reporter plasmid. As shown in figure 4, HF suppressed AED-mediated
AR transcription activity by about 40%. The compounds tested decreased AED-mediated
AR transcription activity by about 75%.
[0055] Example 6. Steroid Hormone Specificity of DHEA Metabolites (No. 4, 6, 8, & 10). The
estrogen receptor (ER)-positive MCF-7 cell line was transfected with a CAT reporter
plasmid containing an estrogen response element linked to the CAT gene. PC-3 cells
were transfected with MMTV-CAT reporter and progesterone receptor (PR) or glucocorticoid
receptor (GR) to test the steroid hormone specificity of reference compounds 4, 6,
8 and 10. All 4 reference compounds have some estrogenic activity and only reference
compound 4, which has a 17α-ethynyl group, shows some weak PR activity. None of these
four reference compounds showed any GR activity.