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:
Jun. 06, 2006
Filed:
Feb. 16, 2005
Applicants:
Waldo Mossi, Biasca, CH;
Patrizio Aspari, Biasca, CH;
Enrico Braglia, Biasca, CH;
Riccardo Braglia, Biasca, CH;
Inventors:
Waldo Mossi, Biasca, CH;
Patrizio Aspari, Biasca, CH;
Enrico Braglia, Biasca, CH;
Riccardo Braglia, Biasca, CH;
Assignee:
Helsinn Advanced Synthesis SA, Biasca, CH;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
C07C 51/00 (2006.01); C07C 51/353 (2006.01);
U.S. Cl.
CPC ...
Abstract
A process for the preparation of 13-cis-retinoic acid (I) from 3-methyl-5-(2,6,6-trimethyl-1-cyclohexen-1-yl)-2,4-pentadienyl)-triphenylphosphonium chloride (IIa) and 5-hydroxy-4-methyl-2(5H)-furanone (III) is herein disclosed. Compounds (IIa) and (III) are reacted in ethanol as the solvent and KOH as the base at a temperature ranging from −5 to 0° C. to give a mixture of retinoic acids which is isomerized to (I) by treatment with a palladium complex.