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:
Dec. 12, 1995
Filed:
Nov. 09, 1993
Applicant:
Inventors:
Gerhard Korb, Hainburg, DE;
Hans-Wolfram Flemming, Usingen, DE;
Assignee:
Hoechst-Roussel Pharmaceuticals Incorporated, Somerville, NJ (US);
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
C07D / ; C07D / ;
U.S. Cl.
CPC ...
544273 ; 544271 ; 544272 ;
Abstract
Process for obtaining 3,7-dialkylxanthines from 3-alkyl-xanthines 3,7-Dialkylxanthines are obtained from the corresponding 3-alkylxanthines using an alkylating agent in the presence of quaternary ammonium and/or phosphonium compounds and, where appropriate, of additional polyethers in a two-phase mixture.