A feeding stimulant for Manduca sexta from Solanum surattenses.

The acceptance of Solanum surattenses as a host plant for the larvae of Manduca sexta was explained by the presence of feeding stimulants in foliage. Bioassay-guided fractionation of plant extracts resulted in the isolation of a highly active compound (1), which was identified as a furostan derivative {26-O-beta-D-glucopyranosyl-(25R)-furosta-5-ene-3-beta-yl-O-alpha-L-rhamnopyranosyl-(1''-2')-O-alpha-L-rhamnopyranosyl-(1'''-3'')-O-beta-D-glucopyranoside}. This compound has the same steroidal core substructure as that in a stimulant (indioside D) previously identified from potato foliage. However, the sugar substituents attached to the core are different.