Cytotoxic ceramides from the Red Sea sponge Spheciospongia vagabunda

Extracts of Egyptian marine organisms from the Red Sea were screened for their anticancer activity using sulforhodamine B assay. The extract of the Red Sea sponge Spheciospongia vagabunda possessed promising anticancer activity against HepG2 (liver cancer cell line) and MCF-7 (breast cancer cell line). Isolation of three new ceramides: N-[(2S,3S,4R)-1,3,4-trihydroxytetradecan-2-yl] tridecanamide (1), (R)-2′-hydroxy-N-[(2S,3S,4R)-1,3,4-trihydroxypentacosan-2-yl] octadecanamide (2) and (R,Z)-2′-hydroxy-N-[(2S,3S,4R)-1,3,4-trihydroxytricosan-2-yl) nonadec-10-enamide (3) was accomplished via bioassay-guided fractionation. Structure elucidation was achieved using spectroscopic techniques, including 1D and 2D NMR and HRMS. Compounds 2 and 3 displayed high potential cytotoxicity against HepG2 (IC50 24.7 and 21.3 µM, respectively) and MCF-7 (IC50 26.8 and 29.8 µM, respectively), compared with doxorubicin as control drug.