3-O-trans-caffeoylisomyricadiol: A new triterpenoid from Tamarix nilotica growing in Saudi Arabia

Abstract

A detailed chemical study of the aerial parts of Tamarix nilotica (Tamaricaceae) from Saudi Arabia led to the isolation of a new pentacyclic triterpenoid, 3-O-trans-caffeoylisomyricadiol, in addition to nine known compounds. The structures of all isolated compounds were unambiguously elucidated by 1D, 2D NMR, and mass spectrometry. In the radical scavenging (DPPH) assay, 3-O-trans-caffeoylisomyricadiol exhibited potent antioxidant activity with an IC50 value of 3.56 μM, while that for quercetin (standard antioxidant) was 5.72 μM. © 2009 Verlag der Zeitschrift für Naturforschung, Tübingen.