Jasminanthoside - a new pregnane-steroid from Jasminanthes tuyetanhiae.

A new pregnane steroid, jasminanthoside (1), together with three known compounds, telosmoside A7 (2), syringaresinol (3), and methyl 6-deoxy-3-O-methyl-ß-D-allopyranosyl-(1→4)-ß-D-oleandropyranoside (4) were isolated from the ethyl acetate extract of Jasminanthes tuyetanhiae roots collected in Vietnam. Their chemical structures were elucidated by NMR and MS spectroscopic data analysis along with the comparison of their data with the published ones in the literature. Although 4 was a known compound, its full NMR data were reported for the first time. All isolated compounds, evaluated for their α-glucosidase inhibition, showed activities stronger than the positive control acarbose. Among them, 1 was the best with the IC50 value of 7.41 ± 0.59 µM.

Telosmoside A21, a new steroid glycoside from the roots of Jasminanthes tuyetanhiae.

A new glycoside, telosmoside A21 (1) and two known compounds, telosmoside A6 (2) and telosmoside A1 (3), were isolated from the roots of Jasminanthes tuyetanhiae. The structure of compound 1 was identified from its spectroscopic data and by comparison with the literature.