Pregnane glycosides from and their α-glucosidase inhibitory activity.

Two new pregnane glycosides, gyminosides A and B ( and ) and three known, tinctoroside B (), tinctoroside C (), and gymnepregoside F () were isolated from the leaves of (Lour.) Decne. Their structures were elucidated by physical and chemical methods and comparing with those reported in the literature. All these compounds were evaluated for -glucosidase assay. Compound exhibited the most anti -glucosidase activity with inhibitory percentage of 63.7 ± 3.9% at the concentration of 200 μM. Compounds - showed moderate anti -glucosidase activity with inhibitory percentage ranging from 40.0 to 52.1%.