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:
Aug. 07, 2001
Filed:
Jan. 26, 1998
Applicant:
Inventors:
Hans Rudolf Müller, Schaffhausen, CH;
Martin Ulmann, Dachsen, CH;
Rudolf Moser, Schaffhausen, CH;
Thomas Ammann, Marthalen, CH;
Assignee:
Eprova AG, Schaffhausen, CH;
Primary Examiner:
Int. Cl.
CPC ...
C07D / ;
U.S. Cl.
CPC ...
C07D / ;
Abstract
Pure and extremely stable crystalline (6S)- and (6R)-tetrahydrofolic acids, absolutely inert even when exposed to air and elevated temperature without stabilizers being added, are prepared by a crystallization process at a pH of ≧3.5 for the preparation of crystalline (6S)-tetrahydrofolic acid and at a pH of ≧2 for the preparation of crystalline (6R)-tetrahydrofolic acid.