PRELIMINARY INVESTIGATION INTO THE PURIFICATION, NMR ANALYSIS, AND MOLECULAR MODELING OF CHONDROITIN SULFATE EPITOPES

Electrophoretic methods are outlined for the rapid purification and analysis of chondroitin sulphate oligosaccharides on a milligram scale. Isomeric impurities however, exist within specific sized oligosaccharides. Detailed H-1 and C-13 NMR data for the chondroitin sulphate disaccharides Delta(4)HexA(1-3)GalNAc6SO(3)(-) and Delta(4)HexA(1-3)GalNAc4SO(3)(-) (prepared from shark chondroitin sulphate) are reported. Two-dimensional NMR methods have been employed in the assignment of spectra. Preliminary models of these disaccharides are proposed from molecular mechanics conformational searching and molecular dynamics procedures. This study provides H-1 and C-13 NMR reference data which will be useful in the investigation of larger chondroitin sulphate oligosaccharides, such as those prepared by the electrophoretic methods mentioned above.