Denigrins A-C: new antitubercular 3,4-diarylpyrrole alkaloids from Dendrilla nigra.

Chemical diversity is vital to antitubercular drug discovery as it ensures a novel bioactivity profile. Marine sponges have so far provided more than 1000 new bioactive molecules. Ethyl acetate extract of the marine sponge Dendrilla nigra on bioactivity-guided screening yielded three new compounds denigrins A-C, with potent antitubercular activity.

Rubrolide R: a new furanone metabolite from the ascidian Synoicum of the Indian Ocean.

A new furanone metabolite of the rubrolide family, rubrolide R as diacetate (1), was isolated from a new species of the ascidian Synoicum, besides the known compounds rubrolide A (as diacetate), cadiolide B and prunolide A. The structure of the new rubrolide was elucidated by a study of spectral data. The crude extract and isolated compounds (prunolide A and cadiolide B) showed antiviral activity against the Japanese encephalitis virus.