Using monosaccharide analysis, absolute configuration determination, methylation analysis and NMR spectroscopy, the complete structure for the O-glycan chain of CcTx was determined to be α--Galp-(1→4)-α--GlcpNAc-(1→6)-[α--Galp-(1→2)-β--Galp-(1→3)-]α--GalpNAc-(1→O)-.