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:
Dec. 30, 2003
Filed:
Apr. 09, 2003
Flavio Villani, Parma, IT;
Antonio Nardi, Paderno Dugnano, IT;
Annibale Salvi, Milan, IT;
Giovanna Falabella, Milan, IT;
Abstract
Process for the synthesis of R(+)&agr;-lipoic acid comprising the following stages: a) Salifying of racemic thioctic acid with R(+)&agr;-methylbenzylamine; b) separation by filtration of the crystallized diastereoisomeric salt of R(+)&agr;-lipoic acid-R(+)&agr;-methylbenzylamine; c) purification by re-crystallization of the diastereoisomeric salt of R(+) &agr;-lipoic acid-R(+)&agr;-methylbenzylamine, in which the re-crystallization solvent consists of a mixture of non-polar/polar solvents; d) separation of the diastereoisomeric salt to obtain R(+)&agr;-lipoic acid by reaction of said salt with acids selected from the group consisting of aliphatic hydroxy-carboxylic acids having 3 to 6 carbon atoms and aqueous phosphoric acid.