Ethyl 6-bromo-3-indolcarboxylate and 3-hydroxyacetal-6-bromoindole, novel bromoindoles from the sponge Pleroma menoui of the Coral sea - Guella, G; Mancini, I; Duhet, D; Richer de Forges, B; Pietra, F (Z Naturforsch C, 1989)