A new diaryheptanoid from the bark of Myrica rubra.

A new diarylheptanoid, (11 xi)-3,5-dimethoxy-11,17-dihydroxy-4,19-diketo-[7,0]-metacyc- lophane, named as rubanol 1, was isolated from the bark of Myrica rubra along with four known compounds (2-5). Their structures were determined by spectroscopic methods including 1D, 2D NMR or comparison with authentic samples. Compound 1 exhibited cytotoxicity against Lun-06, Neu-04, and Bre-04 cell lines with GI50 values of 16.03-32.58 microg mL(-1).