6-Bromo-5-hydroxy-3-indolecarboxyaldehyde from the Caribbean sponge Oceanapia bartschi

The organic extract from Oceanapia bartschi has been shown to contain the antibiotic diterpene Ambliol A (1) and three indole derivatives, 3-bromoindole (2), 6-bromo-3-indolecarboxyaldehyde (3), and 6-bromo-5-hydroxy-3-indolecarboxyaldehyde (4). The structure of the novel compound 4 has been established from its spectroscopic (1H and 13C NMR, UV, IR, and MS) data