Wegerski Christopher J, France Dennis, Cornell-Kennon Susan, Crews Phillip
Department of Chemistry and Biochemistry and Institute of Marine Sciences, University of California, Santa Cruz, CA 95064, USA.
Bioorg Med Chem. 2004 Nov 1;12(21):5631-7. doi: 10.1016/j.bmc.2004.07.061.
Fourteen collections of the marine sponge Stelletta clavosa have been obtained from diverse Indo-Pacific locations in order to conduct a comparison of their major constituents. The dichloromethane extract of one collection (no. 00369) exhibited activity in a c-Raf-1 kinase assay. Bioactivity-directed isolation resulted in the known porphyrin analogs pyropheophorbide a (2) and purpurin 18 methyl ester (3). Further spectroscopic screening of the various sponge extracts resulted in the isolation of four swinholide polyketides, a carotenoid, and three diketopiperazines. Pyropheophorbide a (2) exhibited the best IC(50) among the porphyrin type compounds (IC(50)<0.31microg/mL). This prompted further screening of 2 against a panel of 85 kinases.
