3,7-Dihydroxy-2,4,6-trimethoxyphenanthrene, A New Phenanthrene from Bulbophyllum Odoratissimum

A new phenanthrene derivative 3,7-dihydroxy-2,4,6-trimethoxyphenanthrene was isolated from the all plant of Bulbophyllum odoratissimum, and its structure was elucidated by extensive spectral studies and chemical transformation. The compound displayed cytotoxicity against the growth of human leukemia cell lines K562 and HL-60, human lung adenocarcinoma A549, human hepatoma BEL-7402 and human stomach cancer cell lines SGC-7901 with IC 50 values of 14.23, 10.02, 3.42, 15.36 and 1.13 mg/ml respectively.