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:
Oct. 15, 1996
Filed:
Mar. 01, 1995
Applicant:
Inventors:
Kimio Hamamura, Chiba Prefecture, JP;
Chiaki Seki, Aichi Prefecture, JP;
Masayuki Konishi, Ibaraki Prefecture, JP;
Assignee:
Eisai Chemical Co., Ltd., , JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
C07C / ;
U.S. Cl.
CPC ...
552310 ;
Abstract
A process for the industrial preparation of the quinone derivative represented by the following general formula: ##STR1## which is an intermediate for chroman derivatives useful as a blood sugar lowering agent, and novel intermediates, encompasses the following: (1) Oxidation of the corresponding hydroquinone derivative, and (2) Hydrolysis of the corresponding acyl hydroquinone derivative with a Claisen alkali, followed by the oxidation of resulting hydrolyzate.