Patent · US Expired

Stable polymorphic form of (E)-N,N-diethyl-2-cyano-3-(3,4-dihydroxy-5-nitrophenyl)acrylamide and the process for its preparation

US5135950A · kind A · utility

33Cited by
2References
10Claims
0Family size

Assignee

Inventors

Key dates

Filing dateOct 31, 1990
Grant dateAug 4, 1992
Priority date
Expiry dateOct 31, 2010

Classification

  • Technology area (CPC A)Human Necessities
  • CPC primaryA61P25/28
  • WIPO fieldOrganic fine chemistry
  • WIPO sectorChemistry

Abstract

Stable and crystallographically essentially pure polymorphic form A of (E)-N,N-diethyl-2-cyano-3-(3,4-dihydroxy-5-nitro-phenyl)acrylamide may be prepared by crystallizing crude synthesis product from lower aliphatic carboxylic acid such as formic or acetic acid with a catalytic amount of hydrochloric or hydrobromic acid added. The product is a potent inhibitor of catechol-O-methyl-transferase enzyme (COMT).

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