Patent · US Expired

Single isomer methylphenidate and resolution process

US6531489B2 · kind B2 · utility

9Cited by
3References
11Claims
0Family size

Assignee

Inventors

Key dates

Filing dateApr 17, 2001
Grant dateMar 11, 2003
Priority date
Expiry dateApr 17, 2021

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC07D211/34
  • WIPO fieldOrganic fine chemistry
  • WIPO sectorChemistry

Abstract

Single isomer methylphenidate, selected from the d- and l-threo-enantiomers, has been obtained in purified form, to the extent of less than 2% by weight of a contaminant selected from resolving agent and ritalinic acid. This is achieved by resolution of a mixture of enantiomers using an O, O′-diaroyltartaric acid as resolving agent.

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