Cytotoxic oleanane-type saponins from Albizia inundata

J Nat Prod. 2011 Mar 25;74(3):477-82. doi: 10.1021/np100702p. Epub 2011 Feb 11.

Abstract

Bioassay-guided fractionation of a CH(2)Cl(2)-MeOH extract of the aerial parts of Albizia inundata resulted in the isolation of two new natural oleanane-type triterpene saponins {3-O-[α-L-arabinopyranosyl(1→6)]-2-acetamido-2-deoxy-β-D-glucopyranosyl oleanolic acid (1) and 3-O-[α-L-arabinopyranosyl(1→2)-α-L-arabinopyranosyl(1→6)]-2-acetamido-2-deoxy-β-D-glucopyranosyl acacic acid lactone (2)} along with seven known saponins {3-O-[α-L-arabinopyranosyl(1→6)]-2-acetamido-2-deoxy-β-D-glucopyranosyl echinocystic acid (3), 3-O-[β-D-xylopyranosyl (l→2)-α-L-arabinopyranosyl(l→6)]-2-acetamido-2-deoxy-β-D-glucopyranosyl acacic acid lactone (concinnoside D) (4), 3-O-[β-D-glucopyranosyl(l→2)]-β-D-glucopyranosyl oleanolic acid (5), 3-O-[α-L-arabinopyranosyl(1→2)-α-L-arabinopyranosyl(l→6)]-β-D-glucopyranosyl oleanolic acid (6), 3-O-[β-D-xylopyranosyl(1→2)-α-L-arabinopyranosyl(l→6)]-β-D-glucopyranosyl oleanolic acid (7), 3-O-[α-L-arabinopyranosyl(l→2)-α-L-arabinopyranosyl(1→6)-[β-D-glucopyranosyl(l→2)]-β-D-glucopyranoside echinocystic acid (8), and 3-O-[β-D-xylopyranosyl(l→2)-α-L-arabinopyranosyl(1→6)-[β-D-glucopyranosyl(l→2)]-β-D-glucopyranoside echinocystic acid (9)}. The structures of 1 and 2 were established on the basis of extensive 2D NMR ((1)H-(1)H COSY or DQF-COSY, HSQC, HMBC, TOCSY, and HSQC-TOCSY) spectroscopic, ESIMS, and chemical methods. Saponins 1, 3, 6, and 7 showed cytotoxicity against human head and neck squamous cells (JMAR, MDA1986) and melanoma cells (B16F10, SKMEL28) with IC(50) values in the range 1.8-12.4 μM, using the MTS assay.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Albizzia / chemistry*
  • Antineoplastic Agents, Phytogenic / chemistry
  • Antineoplastic Agents, Phytogenic / isolation & purification*
  • Antineoplastic Agents, Phytogenic / pharmacology*
  • Argentina
  • Drug Screening Assays, Antitumor
  • Humans
  • Molecular Structure
  • Nuclear Magnetic Resonance, Biomolecular
  • Oleanolic Acid / analogs & derivatives*
  • Oleanolic Acid / chemistry
  • Oleanolic Acid / isolation & purification*
  • Oleanolic Acid / pharmacology
  • Saponins / chemistry
  • Saponins / isolation & purification*
  • Saponins / pharmacology
  • Stereoisomerism

Substances

  • 3-O-(alpha-L-arabinopyranosyl(1-2)-alpha-L-arabinopyranosyl(1-6))-2-acetamido-2-deoxy-beta-D-glucopyranosyl acacic acid lactone
  • 3-O-(alpha-L-arabinopyranosyl(1-6))-2-acetamido-2-deoxy-beta-D-glucopyranosyl oleanolic acid
  • Antineoplastic Agents, Phytogenic
  • Saponins
  • Oleanolic Acid