Acasiane A and B and farnesirane A and B, diterpene derivatives from the roots of Acacia farnesiana.

Four new diterpenes, acasiane A ( 1), acasiane B ( 2), farnesirane A ( 3), and farnesirane B ( 4), along with three known diterpenes ( 5 - 7), two triterpenes ( 8 and 9), and eight flavonoids ( 10 - 17) were isolated from the roots of Acacia farnesiana. The structures and relative configurations of these compounds were determined by various spectroscopic and x-ray analyses. All isolated compounds were evaluated for their in vitro cytotoxic activities against six human cancer cell lines (Hep G2, Hep 3B, MDA-MB-231, MCF-7, A549, and Ca9 - 22) with the MTT method.