Antineoplastic agents. 545. Isolation and structure of turbostatins 1-4 from the Asian marine mollusk Turbo stenogyrus

The cancer cell line bioassay-guided separation of an extract from the marine mollusk Turbo stenogyrus led to the isolation of four new cerebrosides designated turbostatins 1-4 (1-4). The structure of each glycolipid was determined by interpreting results of a series of HR-APCI-MS and NMR (1D and 2D) spectral analyses. All four turbostatins exhibited significant (GI50 0.15-2.6 microg/mL) cancer cell growth inhibition against the murine P388 lymphocytic leukemia and a panel of human cancer cell lines.