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:
Mar. 13, 2001
Filed:
Dec. 17, 1998
Shau-Wei Tsai, Tainan, TW;
Chun-Sheng Chang, Tainan, TW;
Abstract
A process for preparing an optically active (S)-&agr;-aryl propionic acid, by hydrolyzing a racemic thioester of &agr;-aryl propionic acid at various temperature in different aqueous organic solvents in the presence of an (S)-stereoselective lipase to form an (S)-&agr;-aryl propionic acid product, while the unreacted (R)-thioester of &agr;-aryl propionic acid can be converted to the corresponding (S)-thioester of &agr;-aryl propionic acid via a racemization reaction by adding a base as the catalyst in the solution and then hydrolyzing by the lipase described as above so that the (S)-&agr;-aryl propionic acid can be obtained theoretically at a conversion of 100% and with high optical purity. The invention also relates to a process for preparing an optically active (S)-&agr;-aryl propionic acid ester, by adding separately additional alcohol in said various organic solvents and carrying out the transesterification of a racemic thioester of &agr;-aryl propionic acid to form an (S)-&agr;-aryl propionic acid ester product, while the unreacted (R)-thioester of &agr;-aryl propionic acid can be converted to the corresponding (S)-thioester of &agr;-aryl propionic acid via a racemization reaction by means of the base added in the solution as the catalyst and then transesterifying again by the lipase as described above so that an (S)-&agr;-aryl propionic acid ester product can be obtained at, theoretically, a conversion of 100% and with high optical purity.