Gr. Pettit et al., ANTINEOPLASTIC AGENTS .277. ISOLATION AND STRUCTURE OF PHAKELLISTATIN-3 AND ISOPHAKELLISTATIN-3 FROM A REPUBLIC-OF-COMOROS MARINE SPONGE, Journal of organic chemistry, 59(7), 1994, pp. 1593-1595
The Western Indian ocean sponge Phakellia carteri was found to contain
two isomeric (at the photo-Trp indole ring juncture) cyclo-heptapepti
des named phakellistatin 3 (3) and isophakellistatin 3 (4).