The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Apr. 12, 1994
Filed:
Jul. 12, 1993
Applicant:
Inventors:
Ramy Lidor, Kfar Saba, IL;
Claude Singer, Kfar Saba, IL;
Assignee:
Teva Pharmaceutical Industries Ltd., Jerusalem, IL;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
C07C / ; C07B / ;
U.S. Cl.
CPC ...
560-7 ; 560 17 ; 562401 ; 562402 ; 562431 ;
Abstract
D(+)-threo-2-hydroxy-3-(2-aminophenylthio)-3-(4-methoxyphenyl)propionic acid, an important intermediate in the synthesis of diltiazem hydrochloride, is obtained in better yields and high optical purity by a novel resolution process comprising the reaction of 2 moles of the (.+-.) racemic acid with 1 mole of quinine and 1 mole of a base in a suitable polar solvent system to form a salt of the D(+) acid and quinine which precipitates; separating said salt and decomposing it with a strong base.