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. 27, 1996
Filed:
Aug. 23, 1995
Applicant:
Inventors:
George C Chiang, Wilmington, DE (US);
Richard F Davis, Newark, DE (US);
Kwaku O Temeng, Wilmington, DE (US);
Assignee:
E. I. Du Pont de Nemours and Company, Wilmington, DE (US);
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
C07D / ; C07D / ; C07D / ; C07D / ;
U.S. Cl.
CPC ...
544211 ; 544206 ; 544208 ; 544321 ; 544323 ; 544332 ;
Abstract
This invention relates to a process for preparing sulfonylureas comprising reacting a sulfonyl chloride with a cyanate salt and an amine base in the presence of an inert aprotic solvent to give an isocyanate complex which is then reacted with an amino heterocycle to form the sulfonylurea product and a process for converting the crystal form of the prepared sulfonylurea product to a more stable crystal product form.