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. 05, 1997
Filed:
Mar. 27, 1996
Applicant:
Inventors:
Iliya Vassilev Ognyanov, Sofia, BG;
Angel Nikolov Konakchiev, Sofia, BG;
Ralph Hanni, Fullinsdorf, CH;
Assignee:
Mepha AG, Aesch, CH;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
C07D / ;
U.S. Cl.
CPC ...
549348 ;
Abstract
Dihydroartemisinin hemisuccinate is prepared by acylation of dihydroartemisinin with 1.0 to 1.3 molar equivalents of succinic anhydride in the presence of 0.5 to 1.5 molar equivalents of tri(C.sub.1 -C.sub.3 -alkyl)amine in a low-boiling, neutral, water-miscible, inert organic solvent or solvent mixture and subsequent isolation of the product at pH 5-8. The product is obtained directly in crystalline form and high yield.