EP 1363893 A1 20031126 - PROCESS FOR PURIFICATION OF WARFARIN ACID, WARFARIN ALKALI METAL SALTS AND CORRESPONDING CLATHRATES
Title (en)
PROCESS FOR PURIFICATION OF WARFARIN ACID, WARFARIN ALKALI METAL SALTS AND CORRESPONDING CLATHRATES
Title (de)
VERFAHREN ZUR REINIGUNG VON WARFARINSÄURE, WARFARIN-ALKALIMETALLSALZEN UND DEN ENTSPRECHENDEN CLATHRATEN
Title (fr)
PROCEDE DE PURIFICATION D'ACIDE DE WARFARINE, SELS METALLIQUES ALCALINS DE WARFARINE ET CLATHRATES CORRESPONDANTS
Publication
Application
Priority
- US 0150438 W 20011228
- US 27173701 P 20010228
Abstract (en)
[origin: WO02070503A1] An improved procedure for the purification of warfarin acid. Sodium, potassium and lithium warfarin salts and the corresponding clathrates are prepared in high, pharmacopeial grade purity and good yields from the pure warfarin acid and the respective metal salt bases in suitable media. The process for preparing pure warfarin acid from crude warfarin acid starts by suspending the crude acid in a water immiscible solvent, extracting the acid into an aqueous solution of dilute base, separating the resulting aqueous phase and diluting it with a lower alkyl alcohol. The aqueous solution is filtered before being diluted with the lower alkyl alcohol. The solution is acidified to a pH of about 2 to 5 using a suitable acid, such as hydrochloric, sulfuric or phosphoric acid. The resulting suspension is stirred at a temperature of from about to 20 DEG C to about 60 DEG C, cooling the suspension below room temperature, filtering the pure warfarin acid and drying.
IPC 1-7
IPC 8 full level
C07D 311/20 (2006.01); C07D 311/46 (2006.01)
CPC (source: EP)
C07D 311/46 (2013.01)
Citation (search report)
See references of WO 02070503A1
Designated contracting state (EPC)
AT BE CH CY DE DK ES FI FR GB GR IE IT LI LU MC NL PT SE TR
DOCDB simple family (publication)
WO 02070503 A1 20020912; BR 0116919 A 20041013; CA 2439488 A1 20020912; CN 1505620 A 20040616; EP 1363893 A1 20031126; IL 157555 A0 20040328; MX PA03007769 A 20050701; RU 2003129000 A 20050510
DOCDB simple family (application)
US 0150438 W 20011228; BR 0116919 A 20011228; CA 2439488 A 20011228; CN 01823159 A 20011228; EP 01985145 A 20011228; IL 15755501 A 20011228; MX PA03007769 A 20011228; RU 2003129000 A 20011228