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:
Nov. 30, 1993
Filed:
Jun. 04, 1992
Applicant:
Inventors:
Friedemann Reiter, Putzbrunn, DE;
Hans-Helmut Henschel, Munich, DE;
Assignee:
Klinge Pharma GmbH, Munich, DE;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
C07C / ;
U.S. Cl.
CPC ...
560 64 ; 562401 ; 562473 ;
Abstract
The preparation of the pure enantiomers of LIFIBROL and its alkyl esters is achieved with surprisingly good yield by reacting the pure enantiomeric forms of S(-) R(+)-4-(4-tert.butylphenyl)-1,2-epoxy butane with 4-hydroxybenzoic acid alkyl ester at elevated temperature in DMF and in the presence of 4-hydroxybenzoic acid alkyl ester sodium salt. Thereafter, the raw reaction product is separated. Either the stereochemically pure LIFIBROL ester is then recovered by recrystallization or the precipitated LIFIBROL enantiomer is made in pure crystalline form by mild alkaline saponification and subsequent acidification.