Constituents of holothuroidea, 17. Isolation and structure of biologically active monosialo-gangliosides from the sea cucumber Cucumaria echinata

Abstract

Three new monosialo-gangliosides, CEG-3 (3), CEG-4 (4), and CEG-5 (5), were obtained, together with two known gangliosides, SJG-1 (1) and CG-1 (2), from the lipid fraction of the chloroform/methanol extract of the sea cucumber Cucumaria echinata. The structures of the new gangliosides were determined on the basis of chemical and spectroscopic evidence to be 1-O-[4-O-acetyl-α- L-fucopyranosyl-(1→11)-(N-glycolyl-α-D-neuraminosyl)-(2→6) -β-D-glucopyranosyl]-ceramide (3) and 1-O-[α-L-fucopyranosyl- (1→11)-(N-glycolyl-α-D-neuraminosyl)-(2→6)-β-D- glucopyranosyl]-ceramide (4, 5). The ceramide moieties of each compound were composed of heterogeneous sphingosine or phytosphingosine bases, and 2-hydroxy or nonhydroxylated fatty acid units. These gangliosides showed neuritogenic activity toward the rat pheochromocytoma cell line PC-12 in the presence of nerve growth factor. © 2006 Pharmaceutical Society of Japan.