Bioactive cubitane diterpenoids from a Colombian gorgonian species of the genus Eunicea

Two new diterpenes having the rare cubitane skeleton were isolated from a southwestern Caribbean gorgonian coral of the genus Eunicea. The structures of the new metabolites, as well as those of three known cubitanes were elucidated by extensive spectroscopic analysis. One compound showed significant in vitro cytotoxic activity against a National Cancer Institute (NCI) panel of cancer cell lines, whereas the remaining metabolites were shown to exert mild antitubercular and antimalarial activities against the pathogenic microbes Mycobacterium tuberculosis and Plasmodium falciparum.