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:
Jul. 21, 1992
Filed:
Aug. 13, 1990
Applicant:
Inventors:
Liang Huang, Beijing, CN;
Geng-tao Liu, Beijing, CN;
Assignees:
Bayer Aktiengesellschaft, Leverkusen, DE;
Chinese Academy of Medical Sciences, Beijing, CN;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
C07D / ;
U.S. Cl.
CPC ...
548544 ; 548534 ;
Abstract
A process for the preparation of compound of the formula ##STR1## in which R.sup.1 --represents ##STR2## and R.sup.2 --represents hydrogen, fluorine, chlorine or bromine. Comprising cyclizing compounds of the formula ##STR3## and, in a further step, either a) reducing stereo-specifically to give compounds of the formula in which R.sup.1 represents ##STR4## or b), to give compounds of the formula in which R.sup.1 represents ##STR5## or by c) forming compounds of the formula ##STR6## followed by stereoselective reduction to give compounds in which R.sup.1 represents ##STR7##