Callyspongiolide, a Cytotoxic Macrolide from the Marine Sponge <i>Callyspongia</i> sp.

A novel macrolide, callyspongiolide, whose structure was determined by comprehensive analysis of the NMR and HRMS spectra, was isolated from the marine sponge <i>Callyspongia</i> sp. collected in Indonesia. The compound features a carbamate-substituted 14-membered macrocyclic lactone ring with a conjugated structurally unprecedented diene-ynic side chain terminating at a brominated benzene ring. Callyspongiolide showed strong cytotoxicity against human Jurkat J16 T and Ramos B lymphocytes