GLYCOLIPIDS FROM MARINE SPONGES: MONOGLYCOSYLCERAMIDES AND ALKYLDIGLYCOSYLGLYCEROLS: ISOLATION, CHARACTERIZATION AND BIOLOGICAL ACTIVITY

Abstract

Monoglycosylceramides have been isolated from the sponges Axinyssa djiferi and Aaptos papillatus, and alkyldiglycosylglycerols have been isolated from Trikentrion laeve and Myrmekioderma dendyi. Glycolipids from Axinyssa djiferi corresponded to a mixture of galactosylceramides, named axidjiferosides, with different ?-hydroxy fatty acids and longchain unsaturated bases, and showed an antimalarial activity. Aaptos papillatus contained glycolipids, named aaptopapillosides, possessing N-acetylglucosamine, a mixture of longchain bases linked to hydroxylated or non hydroxylated fatty acyl chains. Acid methanolysis of mixtures of glycosylceramides homologues allowed to characterize their three parts by GCMS: sugar unit, fatty acyl chains and bases. Glycolipids from M. dendyi had xylose, Nacetylglucosamine, a glycerol backbone and two alkyl long-chains with a terminal primary alcohol group. An O-alkyl-O-glycosylglycerol, known in T. laeve, was isolated in order to perform pharmacological screening, and was found to be associated with a series of glycolipids differing by chain length and unsaturation pattern. Ether glyceroglycolipids showed antitumor activity.