New flavonoids from the stem bark of Erythrina caffra Thunb

Nat Prod Res. 2014;28(9):667-73. doi: 10.1080/14786419.2014.895726. Epub 2014 Mar 25.

Abstract

Three new flavonoids 5,7-dihydroxy-2',4'-dimethoxy-5'-formylisoflavanone (erycaffra E) (1), 5,7-dihydroxy-3'-(2″-hydroxy-3″-methylbut-3-enyl)-5'-(3‴-hydroxy-3‴-methyl-trans-but-1-enyl)-4'-methoxyflavanone (erycaffra D) (2) and 5,7-dihydroxy-4'-methoxy-3',5'-di-(3″-hydroxy-3″-methyl-trans-but-1-enyl)flavanone (erycaffra F) (3) were isolated from the stem bark of Erythrina caffra along with four known compounds, namely 5,4'-dihydroxy-6-(3″-methylbut-2″-enyl)-5‴-hydroxyisopropyldihydrofurano[2‴,3‴:7,8]isoflavone (isosenegalensein) (4), 5,7-dihydroxy-4'-methoxy-3'-(3″-methylbut-2-enyl)-5'-(3‴-hydroxy-3‴-methylbut-1-enyl)flavanone (burttinone) (5), 5,4'-dihydroxy-5″-hydroxyisopropyldihydrofurano[2‴,3‴:7,6]isoflavone (erythrinin C) (6) and 5,4'-dihydroxy-6″-hydroxymethyl-6″-methylpyrano[2″,3″:6,7]isoflavone (erysubin B) (7). The structures were determined on the basis of spectroscopic data (1D, 2D NMR and MS) and by comparison with literature values.

Keywords: Erythrina caffra; fabaceae; flavanone; isoflavanone; isolation.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Botswana
  • Erythrina / chemistry*
  • Isoflavones / chemistry
  • Isoflavones / isolation & purification*
  • Molecular Structure
  • Nuclear Magnetic Resonance, Biomolecular
  • Plant Bark / chemistry
  • Plants, Medicinal / chemistry*
  • Stereoisomerism

Substances

  • 5,7-dihydroxy-2',4'-dimethoxy-5'-formylisoflavanone
  • 5,7-dihydroxy-3'-(2'-hydroxy-3'-methylbut-3-enyl)-5'-(3''-hydroxy-3'-methyl-trans-but-1-enyl)-4'-methoxyflavanone
  • Isoflavones