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. 20, 1982
Filed:
Nov. 24, 1980
Naohito Ohashi, Nishinomiya, JP;
Hiroyuki Mizote, Ibaraki, JP;
Isamu Maruyama, Minoo, JP;
Shoji Nagata, Toyonaka, JP;
Kikuo Ishizumi, Toyonaka, JP;
Junki Katsube, Toyonaka, JP;
Sumitomo Chemical Company, Limited, Osaka, JP;
Abstract
A process for the optical resolution of DL-.alpha.-methyl-.beta.-acylthiopropionic acid, which comprises contacting a DL-.alpha.-methyl-.beta.-acylthiopropionic acid of the formula, ##STR1## wherein R.sub.1 is acetyl or benzoyl which may be substituted with a C.sub.1 -C.sub.3 alkyl or a halogen atom, with an optically active amine of the formula, ##STR2## wherein R.sub.2 is methyl, isopropyl or isobutyl, to form diastereoisomeric salts, subjecting the formed diastereoisomeric salts to the fractional crystallization in a solvent to separate the D-acid salt from the L-acid salt, and then contacting the individual diastereoisomeric salt with acid to give D-.alpha.-methyl-.beta.-acylthiopropionic acid and L-.alpha.-methyl-.beta.-acylthiopropionic acid, the former being useful as an intermediate for synthesizing captopril useful as an antihypertensive agent.