Five new degraded diterpenoids from Trigonostemon xyphophylloides.

Five new degraded diterpenoids trigoxyphins J-N (1-5), among them trigoxyphins K and L have a novel carbon skeleton, together with four known analogues (6-9) have been obtained from the ethanol extract of the twigs of Trigonostemon xyphophylloides. Compounds 1-5 were evaluated for their cytotoxic activity in vitro against three human tumor cell lines by MTT assay. The results exhibited that Trigoxyphin N (5) showed moderate cytotoxicities against SPC-A-1 and SGC-7901 cancer cell lines.

Trigoxyphins H and I: two new daphnane diterpenoids from Trigonostemon xyphophylloides.

Two new daphnane diterpenoids (1 and 2), together with four known analogues (3-6) were isolated from Trigonostemon xyphophylloides. Their structures were elucidated by spectroscopic analysis. Compounds 1 and 2 were evaluated for in vitro cytotoxic activities against the SPCA-1 (human lung cancer) and BEL-7402 (human hepatocellular carcinoma) cancer cell lines.