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:
Jan. 14, 1992
Filed:
Feb. 22, 1990
Applicant:
Inventors:
Atsunori Sano, Saitama, JP;
Masami Ishihara, Kawagoe, JP;
Jun Yoshihara, Kawagoe, JP;
Hiroyoshi Nawa, Fujimi, JP;
Assignees:
Wako Pure Chemical Industries, Ltd., Tokyo, JP;
Tokyo, Tanabe Co., Ltd., Tokyo, JP;
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
C07D / ;
U.S. Cl.
CPC ...
544282 ; 546276 ;
Abstract
3-Tetrazolylpyrido[1,2-a]pyrimidin-4-one derivatives useful as an antiallergy agent are produced by reacting a cyano derivative of pyrido[1,2-a]pyrimidin-4-one compound with (i) hydrazoic acid, followed by hydrolysis, or with (ii) a salt of hydrazoic acid, reacting the resulting product with an acid or a base, followed by hydrolysis.