Solanum incanum and S. heteracanthum as sources of biologically active steroid glycosides: Confirmation of their synonymy

A new spirostanol saponin (1), along with four known saponins, dioscin (2), protodioscin (3), methyl-protodioscin (4), and indioside D (5), and one known steroid glycoalkaloid solamargine (6) were isolated from the two synonymous species, Solanum incanum and S. heteracanthum. The structure of the new saponin was established as (23S,25R)-spirost-5-en-3β,23-diol 3-O-{β-d-xylopyranosyl-(1→2)-O-α-l-rhamnopyranosyl-(1→4)-[O-α-l-rhamnopyranosyl-(1→2)]-β-d-glucopyranoside}, by using a combination of 1D and 2D NMR techniques including 1H, 13C, COSY, TOCSY, NOESY, HSQC and HMBC experiments and by mass spectrometry. The compounds 1, 3, 4 and 5 were evaluated for cytotoxicity against five cancer cell lines and for antioxidant and cytoprotective activity.

A new spirostanol saponin, along with four known saponins, and one known steroid glycoalkaloid solamargine were isolated from the two synonymous species, Solanum incanum and S. heteracanthum. Compounds 1 and 3-5 were evaluated for cytotoxicity against human cancer cell lines and for antioxidant and cytoprotective activity.242