Previously undescribed pyridyl-steroidal glycoalkaloids and 23S,26R-hydroxylated spirostanoid saponin from the fruits of Solanum violaceum ortega and their bioactivities

Three previously undescribed pyridyl-steroidal glycoalkaloids, solanindiosides A‒C, one rare 23S,26R-hydroxylated spirostanoid saponin, and two steroidal alkaloid aglycones, solanindins A and B, derived from the acid hydrolysis of solanindiosides A‒C, were isolated from the fruits of Solanum violaceum, together with five known analogues, including two rare steroidal glycosides, two lignans and a diterpene. Structurally, they comprise a...