Monoterpenoid coumarins from the peels of Clausena lansium.

A phytochemical investigation on the peels of Clausena lansium (Lour.) Skeels led to the isolation of two new monoterpenoid coumarins, named clauslactone V (1) and clauslactone W (2), together with three known analogues (3-5). Their structures were elucidated by spectroscopic techniques (UV, IR, MS, 1D and 2D NMR). All the compounds were evaluated for hypoglycemic activity, and compounds 1-5 showed alpha-glucosidase inhibitory activity in vitro.