Process for the enantioselective preparation of (.beta.-1)-hydroxyalkylxanthines by reduction using Rhodotorula rubra
AssigneeHoechst Aktiengesellschaft
InventorsWerner Aretz, Harald Furrer, Ulrich Gebert, Heinz-Joachim Hinze
Life of this patent
Estimating the term…
Abstract
A Rhodotorula rubra strain has been found which reduces pentoxifylline to 100% to give the S-alcohol. Moreover, other oxoalkylxanthine derivatives can also be converted into the corresponding S-alcohol. The microbiologically obtained S-(+)-enantiomers can then be converted stereoselectively into the respective R-(-)-enantiomers. The corresponding S-alcohols and the R-alcohols obtained by enantioselective inversion of configuration cause an increase in cerebral blood flow.
Claims8
A process for the enantioselective preparation of an (.omega.-1)-hydroxyalkylxanthine which comprises incubating the compound of the formula I ##STR2## in which R.sup.1, R.sup.2 and R.sup.3, which can be identical or different, are selected from the group consisting of the substituents CH.sub.3 --CO--(CH.sub.2).sub.m -- and (C.sub.1 to C.sub.6)-alkyl, where one of the substituents of the group must be CH.sub.3 --CO--(CH.sub.2).sub.m, m is an integer from 2 to 6, and (C.sub.1 to C.sub.6)-alkyl can be straight-chain or branched, or
- in which
- R.sup.1 is CH.sub.3 --CO--(CH.sub.2).sub.4 --, R.sup.2 is CH.sub.3 -- and R.sup.3 is CH.sub.3 --O--CH.sub.2 --, with Rhodotorula rubra DSM 5436 to prepare S-(+)-(.omega.-1)-hydroxyalkylxanthine, and recovering said S-(+)-(.omega.-1)-hydroxyalkylxanthine.
Dependencies are inferred from the claim text.