Synthesis and fibroblast growth factor binding of oligosaccharides related to heparin and heparan sulphate

A series of six disaccharides, α-L-IdoA-(l —»4)-α-D-GlcNAc-l—»OMe, α-L-IdoA-(l -→4)-α-D-GlcNS0³-l-→OMe, β-D-GlcA-(l-→4)-α-D-GlcNAc-l -→OMe, β-D-GlcA-(l-→4)-α-D-GlcNS0³-l-→0Me, α-D-GlcNAc-(l-»4)-β-D-GlcA-l-» OMe, β-D-GlcNAc-(l-^4)-β-D-GlcA*l—→OMe, and two trisaccharide, P-D-GlcA-(l →4)-a-D-GlcNAc-(l -→4)-β-D-GlcA-l -→OMe, a-L-IdoA-(l-»4)-a-D-GlcNS0³-(l —→4)-p-D-GlcA-l —→OMe was prepared and screened for biological activity in vitro. The oligosaccharides were tested, together with a previously synthesized trisaccharide, α-L-IdoA-(l-»4)-α-D-GlcNAc-(l-»4)-β-GlcA-l-»OMe, and three tetrasaccharides, α-L-IdoA-(l-»4)-α-D-GlcNAc-(1 -»4)-β-D-GlcA-(l→3)-β-D-Gal-l -→OMe, β-D-GlcA-(l -→3)-β-D-Gal-(l -»3)-β-D-Gal-(l-*3)-2-P0³-β-D-Xyl-l-→0Me, β-D-GlcA-(l-43)-β-D-Gal-(l-→3)-β-D-Gal-(1—»3)-β-D-Xyl-l-»OMe, for competitive binding to acidic and basic fibroblast growth factor in an assay using ¹²⁵I labelled heparin. It was found that the non-sulphated trisaccharides, a-L-IdoA-(l-*4)-a-D-GlcNAc-(l—→4)-p-D-GlcA-1—*OMe and p-D-GlcA-(l-»4)-a-D-GlcNAc-(l-→4)-p-D-GlcA-l-→OMe, and two of the disaccharides can bind to acidic as well as basic FGF.