Synthesis, inhibitory effects on nitric oxide and structure-activity relationships of a glycosphingolipid from the marine sponge Aplysinella rhax and its analogues

Abstract

The novel glycosphingolipid, β-D-GalNAcp(1→4)[α-D- Fucp(1→3)]-(3-D-GlcNAcp (1→Cer (A), isolated from the marine sponge Aplysinella rhax has a unique structure, with D-fucose and N-acetyl-D- galactosamine moieties attached to a reducing-end N-acetyl-D-glucosamine through an α1→3 and (β1→4 linkage, respectively. We synthesized glycolipid 1 and some non-natural di-and trisaccharide analogues 2-6 containing a D-fucose residue. Among these compounds, the natural type showed the most potent nitric oxide (NO) production inhibitory activity against LPS-induced J774.1 cells. Our results indicate that both the presence of a D-Fucα1-3GlcNAc-linkage and the ceramide aglycon portion are crucial for optimal NO inhibition. © 2011 by the authors.