Patent · US Expired

Resolution of .alpha.-pivaloyloxyethyl-(S)-3-(3,4-dihydroxyphenyl)-2-methylalantinate into its .alpha. and .beta. isomers

US4404392A · kind A · utility

0Cited by
2References
9Claims
0Family size

Assignee

Inventors

Key dates

Filing dateNov 16, 1981
Grant dateSep 13, 1983
Priority date
Expiry dateNov 16, 2001

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC07B2200/07
  • WIPO fieldOrganic fine chemistry
  • WIPO sectorChemistry

Abstract

Resolution of the .alpha. and .beta. isomers of .alpha.-pivaloyloxyethyl-(S)-3-(3,6-dihydroxyphenyl)-2-methylalaninate is accomplished by; (a) forming the (+) hydrogen tartrate salt of the mixture; (b) fractionally crystallizing the .beta.-isomer salt; and (c) recovering the .alpha.-isomer from the mother liquor by treatment with first a base and second a mineral acid.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.