Patent · US Expired

Isomerization process

US5908957A · kind A · utility

3Cited by
4References
12Claims
0Family size

Assignee

Inventor

Key dates

Filing dateJan 26, 1998
Grant dateJun 1, 1999
Priority date
Expiry dateJan 26, 2018

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC07C2601/16
  • WIPO fieldOrganic fine chemistry
  • WIPO sectorChemistry

Abstract

A process is disclosed for the catalyzed isomerization of a Z-isomer of a vitamin A compound or of a mixture of several of such isomers into a mixture of the corresponding all-E- and 13-Z-isomers of this vitamin A compound. The process utilizes nitrogen monoxide or a gas mixture containing nitrogen monoxide as the isomerization catalyst. Vitamin A acetate or vitamin A acid is preferably used as the vitamin A compound. The thus-produced all-E vitamin A and its alkanoyl esters have of all isomers by far the highest biological activity and are accordingly almost exclusively used in human and animal nutrition. The 13-Z-vitamin A compounds in turn play an important role as pharmaceutically active substances.

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