1--Alkylglycerol Ethers from the Marine Sponge and Their Cytotoxic Activity.

The cytotoxicity-bioassay-guided fractionation of the ethanol extract from the marine sponge , whose 1--alkyl--glycerol ethers (AGEs) have not been investigated so far, led to the isolation of a complex lipid fraction containing, along with previously known compounds, six new lipids of the AGE type. The composition of the AGE fraction as well as the structures of 6 new and 22 previously known compounds were established using H and C NMR, GC/MS, and chemical conversion methods. The new AGEs were identified as: 1--(Z-docos-15-enyl)--glycerol (), 1--(Z-docos-17-enyl)--glycerol (), 1--(Z-tricos-15-enyl)--glycerol (), 1--(Z-tricos-16-enyl)--glycerol (), 1--(Z-tricos-17-enyl)--glycerol (), and 1--(Z-tetracos-15-enyl)--glycerol (). The isolated AGEs show weak cytotoxic activity in THP-1, HL-60, HeLa, DLD-1, SNU C4, SK-MEL-28, and MDA-MB-231 human cancer cells. A further cytotoxicity analysis in JB6 P Cl41 cells bearing mutated MAP kinase genes revealed that ERK2 and JNK1 play a cytoprotective role in the cellular response to the AGE-induced cytotoxic effects.