Anti-infective Discorhabdins from a Deep-Water Alaskan Sponge of the Genus Latrunculia

Bioassay- and LC-MS-guided fractionation of a methanol extract from a new deep-water Alaskan sponge species of the genus Latrunculia resulted in the isolation of two new brominated pyrroloiminoquinones, dihydrodiscorhabdin B and discorhabdin Y (2), along with six known pyrroloiminoquinone alkaloids, discorhabdins A (3), C (4), E (5), and L (6), dihydrodiscorhabdin C (7), and the benzene derivative 8. Compounds 3, 4, and 7 exhibited anti-HCV activity, antimalarial activity, and selective antimicrobial activity. Although compounds 3 and 7 displayed potent and selective in vitro antiprotozoal activity, Plasmodium berghei-infected mice did not respond to these metabolites due to their toxicity in vivo.