Racemization of 6-methoxydihydrosanguinarine in methanol investigated by enantioselective dynamic HPLC

J Pharm Biomed Anal. 2010 Jan 5;51(1):103-6. doi: 10.1016/j.jpba.2009.08.014. Epub 2009 Aug 18.

Abstract

A biologically active benzophenanthridine alkaloid, 6-methoxydihydrosanguinarine (MS), was isolated from Hylomecon plants. Although enantiomers of MS can be separated by chiral HPLC, its isomers rapidly form a racemic mixture in methanol. The rate constants for the racemization of MS enantiomers were 9.20x10(-4)s(-1) and 9.95x10(-4)s(-1) for (+)-MS and (-)-MS, respectively, as determined by dynamic HPLC and chiral chromatography. This unusually rapid racemization may originate from the formation of a stable iminium ion intermediate, sanguinarine. Therefore, the variety of biological activities exhibited by MS may be attributable to a combination of (+)-MS, (-)-MS, and sanguinarine.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Benzophenanthridines / analysis
  • Benzophenanthridines / chemistry*
  • Chemistry, Pharmaceutical / methods
  • Chromatography, High Pressure Liquid / methods*
  • Isoquinolines / analysis
  • Isoquinolines / chemistry*
  • Methanol / chemistry
  • Papaveraceae / chemistry*
  • Plant Extracts / chemistry
  • Solvents / chemistry
  • Stereoisomerism

Substances

  • 6-methoxydihydrosanguinarine
  • Benzophenanthridines
  • Isoquinolines
  • Plant Extracts
  • Solvents
  • sanguinarine
  • Methanol