Vaticanol G (1) and vaticaside D (2) isolated from stem bark of Vatica rass
ak (Dipterocarpaceae) were the first instance of stilbenoid trimers with an
unusual tribenzobicyclo[3.3.2]decatriene system. Vaticanols D (3) and H (4
)-J (6) were elucidated to be a stilbenoid hexamer or heptamer containing a
structurally identical trimeric unit. Their structures and the relative co
nfigurations were established on the basis of 2D NMR spectroscopy. The hexa
mers (3, 4 and 5) and the heptemer (6) showed cytotoxicity against KB cells
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