| Abstract: | Twelve 3,8‐epoxy iridoids, including four new compounds, jatamanins R–U ( 1 – 4 ), and eight known compounds ( 5 – 12 ), were obtained from the roots and rhizomes of Valeriana jatamansi. The structures were elucidated from analysis of spectroscopic data. The absolute configurations of 1 – 4 were determined by comparison of experimental and literature ECD spectra. Moreover, the compounds were evaluated for cytotoxic effects against glioma stem cells, inhibition of NO production, activity against influenza A virus and reversal of multidrug resistance of HepG2/ADR cells. Compounds 9 and 12 showed significant cytotoxic potency against GSC‐18# (IC50=1.351 and 4.439 μg ml?1, respectively) and GSC‐3# (IC50=10.88 and 6.348 μg ml?1, respectively) glioma stem cells, while compound 12 was also slightly less potent against GSC‐12# (IC50=13.45 μg ml?1) glioma stem cell growth. In addition, compounds 9 and 12 displayed obvious inhibition of NO production (IC50=4.6 and 15.8 μm , respectively). |
