Cytotoxic Flavonoids and New Chromenes fromFicus formosanaf.formosana

Abstract
Two new chromenes, ficuformodiol A (1) and ficuformodiol B (2), and nine known compounds including one chromene, spatheliachromen (3), six flavonoids, obovatin (4), carpachromene (5), apigenin (6), norartocarpetin (7), steppogenin (8), 6-prenylpinocembrin (9), one benzopyran, chromenylacrylic acid (10), and one isocoumarin, (R)-(-)-mellein (11), were obtained from the cytotoxic chloroform-soluble fraction of the stems of Ficus formosana f. formosana (Moraceae). Their structures were determined by means of spectroscopic analyses. Compounds 5, 6 and 7 exhibited significant cytotoxicity against HepG2, PLC/PRF/5 and Raji cancer cell lines in vitro.