Polyketide-peroxides from a Species of Jamaican Plakortis (Porifera: Demospongiae)

A new cyclic peroxide plakortisinic acid (1), and a new ketone derivative (2), in addition to six known compounds, an alpha,beta-unsaturated ester (3), plakortide N (4), plakortide F (5) and its free acid (6), plakortone D (7), and a furan-containing molecule (8), were isolated from a species of Plakortis from Jamaica. The structures were elucidated by interpretation of 1D and 2D NMR spectra, and mass spectrometry data and by comparison with data from the literature. Comparison between experimental and calculated optical rotations allowed the assignment of absolute configuration of 1 and 2. The isolated compounds have been evaluated for their antimicrobial, antimalarial, anticancer, anti-Mtb, and anti HIV-1 activity.