Neopeltolide, a macrolide from a lithistid sponge of the family Neopeltidae.

A new marine-derived macrolide designated as neopeltolide (1) has been isolated from a deep-water sponge of the family Neopeltidae. Its structure was elucidated on the basis of spectroscopic data interpretation. Neopeltolide (1) is a potent inhibitor of the in vitro proliferation of the A-549 human lung adenocarcinoma, the NCI-ADR-RES human ovarian sarcoma, and the P388 murine leukemia cell lines, with IC50's of 1.2, 5.1, and 0.56 nM, respectively. Neopeltolide (1) also inhibited the growth of the fungal pathogen Candida albicans with a minimum inhibitory concentration of 0.62 microg/mL.