Two pairs of unusual melibiose and raffinose esters from Scrophularia ningpoensis

A pair of unusual melibiose esters (1α/1β) and a pair of unusual raffinose esters (2α/2β), were isolated from Scrophularia ningpoensis. Structures of them were established by detailed spectroscopic analyses to be 6-O-(E)-cinnamoyl-α-d-galactopyranosyl-(1→6)-α(β)-d-glucopyranose (1α/1β) and 6-O-(E)/(Z)-cinnamoyl-α-d-galactopyranosyl-(1→6)-α-d-glucopyranosyl-(1→2)-β-d-fructofuranose (2α/2β), respectively. All these compounds were evaluated for antifouling activity against the settlement of Balanus amphitrite larvae, along with the cytotoxic effect against the proliferation of HeLa cell lines.