Phakellia mauritiana

Dibromophakellstatin (66) from the Indian Ocean sponge Phakellia mauritiana shows GIso-level growth inhibition of one-third of the NCI s 60 cell line human tumor panel at submicromolar concentrations [60]. 

Pettit GR, McNulty J, Herald DL, Doubek DL, Chapuis J-C, Schmidt JM, Tackett LP, Boyd MR (1997) Antineoplastic Agents. 362. Isolation and X-ray Crystal Structure of Dibromophakellstatin from the Indian Ocean Sponge Phakellia mauritiana. J Nat Prod 60 180... 

More recently, some closely related analogs of phakellins have been obtained. Firstly, the phakellins 43 and 44, enantiomeric to 41 and 42, respectively, were obtained from Pseudaxynissa cantharella [51] later, the 7-N-methylphakellins 45 and 46 were isolated from an Agelas sp. [72], and phakellistatin (47) from Phakellia mauritiana [73]. This last compound was reported to exhibit potent cell growth inhibitory activity against a variety of human cancer cell lines (ED50 from 0.3 to 4.0 p,M) [73]. 

Pettit, G.R., McNulty, J., Herald, D.L., Doubek, D.L., Chapuis, J.C., Schmidt. J.M., Tackett, L, and Boyd, M.R. (1997) Antineoplastic agents. 362. Isolation and X-ray crystal structure of dibromophakellstatin from the Indian Ocean sponge Phakellia mauritiana. J. Nat. Prod., 60,180-183. 

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