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. 02, 1984
Filed:
Jun. 29, 1983
Applicant:
Inventors:
Ludwig Zirngibl, Zofingen, CH;
Rene Gnehm, Kungoldingen, CH;
Assignee:
Siegfried Aktiengesellschaft, Zofingen, CH;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
C07D / ;
U.S. Cl.
CPC ...
544 49 ;
Abstract
In the preparation of 4-hydroxy-2-methyl-N-2-pyridyl-2H-benzothiazine-3-carboxamide 1,1-dioxide by reacting the corresponding 3-methoxycarbonyl compound with 2-aminopyridine, a dramatic increase in the yield is obtained if the reaction is carried out in the presence of 0.1 to 1.5 mole equivalent (based on the 3-methoxycarbonyl compound) of an alkyl- or arylsulfonic acid.