Toonapolyynes A-D, new polyynes from Toona ciliata.

Phytochemical investigation on the leaves and twigs of Toona ciliata has led to the isolation of four new polyynes (1-4) and two knowns (5 and 6). Their structures were determined by extensive spectroscopic analysis (MS, UV, IR, and NMR) and Mosher's method. All compounds were evaluated for their inhibitory activities against HepG2 human tumor cell line but were inactive.