Iridoid Glycosides from Roots of Verbascum laxum

Abstract

A new dimeric iridoid laxoside with the structure 6′′′-O-[6-O-(4″-trans-p-methoxycinnamoyl)-5-hydroxyaucubigenin-(1→1′)-O-β-D-galactopyranosyl]-6″″-O-trans-p-methoxycinnamoylaucubin and 10-O-p-coumaroylharpagide (harpagoside) were isolated from roots of Verbascum laxum Fil. & Jav. The structures of the iridoids were established based on chemical transformations; UV, IR, PMR, and 13C NMR spectral data; two-dimensional HSQC, HMBC, DEPT, and COSY experiments; and mass spectrometry.