New iridoid glycoside from Gratiola officinalis

A new iridoid glycoside, 1β,6β-di-O-trans-cinnamoyl-9-O-β-D-glucopyranosyl-3-iridene-5β-ol (1), along with four known compounds loliolide (2), β-sitosterol-3-O-β-D-glucopyranoside (3), betulinic acid (4), and β-amyrin (5), was isolated from the aerial parts of Gratiola officinalis L. The structure of the new compound was deduced on the basis of 1D ¹H and ¹³C NMR and 2D HMQC, HMBC, and COSY experiments, and mass spectrometric techniques (EI-MS and HR-EI-MS). The relative configuration of 1 was assigned by comparative analysis of the NMR spectral data with known analogs, together with NOESY experiments.