SYNTHESIS AND CHARACTERIZATION OF HIGHLY GLYCOSYLATED GLYCOPEPTIDES WITH T-N-ANTIGENIC STRUCTURES CORRESPONDING TO HUMAN GLYCOPHORIN A(N)

Two highly glycosylated O-glycopeptides corresponding to human glycoph orin A(N) With T-n-antigenic structures were synthesised. The first gl ycopeptide has two glycosylated clusters with three and six adjacent 2 -acetamido-2-deoxy-D-galactose (GalNAc) glycosylation sites and repres ents the N-terminal octadecapeptide from Leu-1 to Lys-18. The second g lycopeptide, a decapeptide from His-9 to Lys-18, contains as a compact cluster six adjacent GalNAc glycosylation sites. The solid phase synt hesis was realised by using the carbohydrate-containing building block s Fmoc-Ser(Ac(3)GalN(3))-Pfp and Fmoc-Thr(Ac(3)GalN(3))-Pfp. The synth esised substances were characterised by NMR spectroscopic techniques. The main techniques used were homonuclear TOCSY and NOESY as well as H MQC and HMBC for C-13,H-1 correlations. (C) 1997 Elsevier Science Ltd.