Patent · US Expired

Resolution of 1,4-dihydropyridine derivatives

US4920225A · kind A · utility

1Cited by
9References
3Claims
0Family size

Assignee

Inventor

Key dates

Filing dateDec 22, 1986
Grant dateApr 24, 1990
Priority date
Expiry dateDec 22, 2006

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC07D211/90
  • WIPO fieldOrganic fine chemistry
  • WIPO sectorChemistry

Abstract

Optically active compounds of formula 1 ##STR1## wherein R.sub.1 is H or lower alkyl; PA1 R.sub.2 and R.sub.6 are each independently lower alkyl, aryl, or arylalkyl; PA1 R.sub.3 is CN, NO.sub.2, CO.sub.2 R.sub.5, CONHR.sub.5, SO.sub.2 R.sub.5, or P(O)(OR.sub.5).sub.2, where R.sub.5 is lower alkyl, lower alkoxyalkyl, aryl, or arylalkyl; PA1 R.sub.4 is aryl, heterocyclyl, or fused-ring heterocyclyl, optionally substituted with one, two, or three halo, NO.sub.2, CN, lower alkyl, lower alkoxy, lower alkylamino, CF.sub.3, OCH.sub.2 F, or OCF.sub.3 ; are prepared by fractional crystallization from hot organic solvent and water in the presence of a suitable optically active amine base.

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