Two novel secoiridoid glucosides from Tripterospermum chinense

Two novel secoiridoid glucosides, tripterospermumcins C (1) and D (2), were isolated from the aerial parts of Tripterospermum chinense, along with four known compounds, tripterospermumcin B (3), sweroside (4), loganic acid (5), and 8-epi-kingiside (6). Their structures were determined by analysis of 1D and 2D NMR data, as well as by comparison with model compounds. Compound 1 was a rare iridoid tetramer with four glucosides.