A new iridoid from the roots of Valeriana jatamansi Jones with α-glucosidase activity.

One new iridoid namely rupesin F ( 1 ) together with four known ones ( 2 - 5 ) were isolated from the roots of Valeriana jatamansi Jones. The structures were established using spectroscopic methods (1D and 2D NMR including HSQC, HMBC, COSY and NOESY) and by comparison with previously published literature data. The isolated compounds 1 and 3 exhibited strong α-glucosidase inhibition activity with IC ₅₀ values of 10.13 ± 0.11 and 9.13 ± 0.03 μg/mL, respectively. This study enriched the chemical diversity of metabolites and provides a direction for the development of antidiabetic agents.