Iridoid and phenylethyl glycosides from Globularia sintenisii

A new iridoid glycoside, sintenoside (1) and two new phenylethyl glycosides, globusintenoside (=2-(3,4-dihydroxyphenyl)ethyl-O-6-O-feruloyl- β-D-glucopyranosyl-(1 → 4)-α-L-rhamnopyranosyl-(1 → 3)-4-O-caffeoyl-β-D-glucopyranoside; 2) and 3‴-O-methylcrenatoside (=1,2-O-[2-(3,4-dihydroxyphenyl)ethan-1,2-diyl]-3-O-α-L-4-O-feruloyl- rhamnopyranosyl-β-D-glucopyranose; 3) were isolated from the underground parts of Globularia sintenisii, along with three known iridoid glycosides, lytanthosalin, globularin, catalpol, and six known phenylethyl glycosides, verbascoside, isoverbascoside, leucoscepthoside A, plantainoside C, martynoside, and isocrenatoside. The structure elucidation of the isolated compounds was performed by spectroscopic methods (MS and 1D and 2D NMR).