The genus Vitex: An overview of iridoids as chemotaxonomic marker

Abstract

In our continuing work on Vitex genus, the phytochemical investigation of leaves of Vitex grandifolia led to the isolation of two iridoids known in the literature as agnuside and bartsioside. The chemical structures were characterized by combined spectroscopic analysis. These compounds were isolated from this specie for the first time, this study give evidence to iridoids as chemotaxonomic marker and their constitutive presence has been reported in a number of genera in the family Lamiaceae. Iridoids have been isolated from nineteen species belonging to genus Vitex from Lamiaceae especially aucubin and agnuside. In addition to the utilization of morphological features of plants belonging to this genus, these compounds may be useful chemotaxonomic markers to aid taxonomic identification. This work evaluates and describes the distribution of iridoids in Vitex species to further establish this claim with structures of the iridoids found in this genus. Keywords: Iridoids, Agnuside, Chemotaxonomic markers, Lamiaceae