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:
Aug. 15, 1978
Filed:
Oct. 20, 1976
Applicant:
Inventors:
Donald E Kuhla, Gales Ferry, CT (US);
Harry A Watson, Jr, New London, CT (US);
Assignee:
Pfizer Inc., New York, NY (US);
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
C07D / ;
U.S. Cl.
CPC ...
542471 ; 260328 ; 260707 ;
Abstract
Trans-N,N-dimethyl-9-[3-(4-methyl-1-piperazinyl)propylidene]-thioxanthene-2 -sulfonamide is isomerized to the cis-isomer by contacting the trans-isomer with strong base in a polar organic solvent. By using an organic solvent in which the solubility of the cis-isomer is substantially less than that of the trans-isomer, the cis-isomer can be selectively precipitated from said solvent, thereby favoring additional isomerization to the cis-isomer in the supernatant, and separated.