Bioactive marine metabolites series, part 109.: Three new bromotyrosine derivatives lethal to crab from the marine sponge, Pseudoceratina purpurea

Three new bromotyrosine-derived metabolites, tokaradines A (1), B (2), and C (3), were isolated from the marine sponge Pseudoceratina purpurea. Their structures were determined by spectral methods. Tokaradines were lethal to the crab Hemigrapsus sanguineus. (C) 2001 Elsevier Science Ltd. All rights reserved.