Two new arylalkenyl α,β-unsaturated δ-lactones with cytotoxic activity from the leaves and twigs of Cryptocarya concinna.

Tow new arylalkenyl α,β-unsaturated δ-lactones named cryptoconcatones K (1) and L (2) were obtained from the leaves and twigs of Cryptocarya concinna. Their structures were established on the basis of spectroscopic data (MS, 1D and 2D NMR). Compounds 1 and 2 showed cytotoxic activities with IC ₅₀ values of 4.5 and 3.9 μM against Huh7 cancer cell line, respectively.