The antileishmanial activity assessment of unusual flavonoids from Kalanchoe pinnata

Phytochemistry. 2006 Sep;67(18):2071-7. doi: 10.1016/j.phytochem.2006.06.027. Epub 2006 Aug 23.

Abstract

The importance of flavonoids for the antileishmanial activity of Kalanchoe pinnata was previously demonstrated by the isolation of quercitrin, a potent antileishmanial flavonoid. In the present study, the aqueous leaf extract from the medicinal plant K. pinnata (Crassulaceae) afforded a kaempferol di-glycoside, named kapinnatoside, identified as kaempferol 3-O-alpha-L-arabinopyranosyl (1-->2) alpha-L-rhamnopyranoside (1). In addition, two unusual flavonol and flavone glycosides already reported, quercetin 3-O-alpha-L-arabinopyranosyl (1-->2) alpha-L-rhamnopyranoside (2) and 4',5-dihydroxy-3',8-dimethoxyflavone 7-O-beta-D-glucopyranoside (3), have been isolated. Their structures were determined via analyses of mono and bi-dimensional (1)H and (13)C NMR spectroscopic experiments and HR-MALDI mass spectra. Because of its restricted occurrence and its abundance in K. pinnata, flavonoid (2) may be a chemical marker for this plant species of high therapeutic potential. The three flavonoids were tested separately against Leishmania amazonenis amastigotes in comparison with quercitrin, quercetin and afzelin. The quercetin aglycone - type structure, as well as a rhamnosyl unit linked at C-3, seem to be important for antileishmanial activity.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Antiprotozoal Agents / isolation & purification
  • Antiprotozoal Agents / pharmacology*
  • Flavonoids / chemistry*
  • Flavonoids / pharmacology*
  • Kalanchoe / chemistry*
  • Leishmania / drug effects*
  • Mannosides / chemistry
  • Mannosides / pharmacology
  • Molecular Structure
  • Parasitic Sensitivity Tests
  • Plant Extracts / chemistry
  • Plant Extracts / pharmacology
  • Plant Leaves / chemistry
  • Proanthocyanidins / chemistry
  • Proanthocyanidins / pharmacology
  • Quercetin / analogs & derivatives
  • Quercetin / chemistry
  • Quercetin / pharmacology

Substances

  • Antiprotozoal Agents
  • Flavonoids
  • Mannosides
  • Plant Extracts
  • Proanthocyanidins
  • quercitrin
  • afzelin
  • Quercetin