Phosphonoglycolipids in Marine Crustacean: Structural Characterization of Two Novel Phosphonocerebrosides, from the Crab, Erimacrus isenbeckii

Abstract

Two novel phosphonoglycolipids, named PnGC₁ and PnGC₂ were isolated from the marine crab, Erimacrus isenbeckii by successive column chromatography on ion exchange Sephadex (DEAE- and QAE-Sephadex) and silicic acid (Iatrobeads). Their chemical structures were characterized as phosphonocerebrosides, 4’-O-(2-aminoethylphosphonyl) Glc_pβ1-1 ceramide for PnGC₁ and 4’-O-(N-methyl-2-aminoethylphosphonyl) Glc_pβ1-1 ceramide for PnGC₂ by IR, MALDI-TOF MS, ¹H-NMR, GC and GC-MS analyses of the water-soluble products after acid hydrolysis, and methylation of the product of hydrogen fluoride degradation. In both phosphonocerebrosides, the ceramide moieties were composed of tetradeca-4-sphingenine as the sole sphingoid, and stearic, arachidic, behenic and docosamonoenoic acids as the major fatty acids.