Cytotoxic and antibacterial activities of iridoids and sesquiterpenoids from Valeriana jatamansi.

Three new iridoids, valejatanins A-C (1-3), and one new natrual iridoid (4), together with four known sesquiterpenoids (5-8), were isolated from the roots of Valeriana jatamansi Jones. Compounds 3 and 4 are C(4)-epimers. Their structures were elucidated by extensive spectroscopic analysis (IR, HRESIMS, 1D and 2D NMR) and by comparison of their NMR data with those of related compounds. The absolute configuration of 5 was determined for the first time by single-crystal X-ray diffraction analysis with Cu-Kα irradiation. The cytotoxic activities of all compounds were evaluated against HT29, K562 and B16 cancer cell lines in vitro by MTT assay. Valejatanin A (1) showed noteworthy cytotoxic activities with IC50 values of 22.17, 15.26, 3.53μg/mL against three cancer cell lines. The antibacterial activities of all compounds against bacteria were tested in vitro. Compound 6 exhibited antibacterial activities against Staphylococcus aureus and Pseudomonas aeruginosa.