Two new bis-coumarin glycosides from Daphne giraldii NITSCHE.

Two new bis-coumarin glycosides were isolated from the stem barks of Daphne giraldii NITSCHE. Their structures were elucidated as 6-O-alpha-L-rhamnnopyranosyl daphnogirin (1), and 6-O-beta-D-apiofuranosyl daphnogirin (2), on the basis of detailed spectroscopic analysis. Compounds 1 and 2 were tested inhibitory effects against production of nitric oxide (NO) in RAW264.7 cells, and cytotoxicity of human tumor cell lines A549, LOVO, QGY-7703, 6T-CEM. The results showed that compounds 1 and 2 neither reduced production of NO, nor inhibited human tumor cell lines.