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:
Feb. 06, 1996
Filed:
Dec. 01, 1993
Applicant:
Inventors:
Pascal Jequier, Melide, CH;
Fabrizio Marazza, Novaggio, CH;
Assignee:
Sapec S.A. Fine Chemicals, Lugano, CH;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
C07D / ;
U.S. Cl.
CPC ...
544258 ;
Abstract
(6S)-THF is obtained by adding, in portions, an acid to an aqueous solution of a (6RS)-diastereoisomeric mixture of an alkali metal salt of 5,6,7,8-tetrahydrofolic acid. The addition is made at a temperature from 5.degree. C. to 80.degree. C. for the purpose of the selective crystallization for a period sufficient to stabilize the pH to a value of from 4.8 to 5.3. Then, the formed solid, i.e., (6S)-5,6,7,8-tetrahydrofolic acid, is separated.