Shaban M A, Jeanloz R W
Carbohydr Res. 1975 Sep;43(2):281-91. doi: 10.1016/s0008-6215(00)83492-8.
Glycopeptides corresponding to sequences 27--28, 48--49, and 58--59 of human plasma alpha1-acid glycoproteins have been synthesized by sequential elongation of the peptide chain at the terminal amino group. 2-Acetamido-3,4,6-tri-O-acetyl-1-N-(L-aspart-4-oyl)-2-deoxy-beta-D-glucopyranosylamine was condensed with the p-nitrophenyl esters of protected amino acids to give the corresponding protected glycodipeptides having the sequences Gly-(GlcNAc-4-)Asn, Pro-(GlcNAc-4-)Asn, Val-(GlcNAc-4-)Asn, Leu-(GlcNAc-4-)Asn, Glu-(GlcNAc-4-)Asn, Tyr-(GlcNAc-4-)Asn, Ser-(GlcNAc-4-)Asn, and Cys-(GlcNAc-4-)Asn. Deprotection of the carbohydrate and of the peptide residues of these compounds was achieved, except for those having N-tert-butyloxycarbonyl protective groups, to give the corresponding free glycopeptides. The glycotripeptide 2-acetamido-1-N-(2-N-[N-(tert-butyloxycarbonyl)-L-glutam-1-oyl-L-tyrosyl]-L-aspart-4-oxy)-2-deoxy-beta-D-glucopyranosylamine, having the amino acid sequence 10--12 of human plasma alpha1-acid glycoprotein, was prepared by condensation of 2-acetamido 3,4,6-tri-O-acetyl-2-deoxy-1-N-[2-N-(L-tyrosyl)-L-aspart-4-oyl[-beta-D-glucopyranosylamine with 5-benzyl 1-p-nitrophenyl N-(tert-butyloxycarbonyl)-L-glutamate, followed by removal of the ester groups.
通过在末端氨基处依次延长肽链，合成了与人血浆α1-酸性糖蛋白序列27 - 28、48 - 49和58 - 59相对应的糖肽。将2-乙酰氨基-3,4,6-三-O-乙酰基-1-N-(L-天冬酰胺-4-酰基)-2-脱氧-β-D-吡喃葡萄糖胺与受保护氨基酸的对硝基苯酯缩合，得到具有序列Gly-(GlcNAc-4-)Asn、Pro-(GlcNAc-4-)Asn、Val-(GlcNAc-4-)Asn、Leu-(GlcNAc-4-)Asn、Glu-(GlcNAc-4-)Asn、Tyr-(GlcNAc-4-)Asn、Ser-(GlcNAc-4-)Asn和Cys-(GlcNAc-4-)Asn的相应受保护糖二肽。除了具有N-叔丁氧羰基保护基团的那些化合物外，这些化合物的碳水化合物和肽残基的去保护得以实现，从而得到相应的游离糖肽。通过将2-乙酰氨基3,4,6-三-O-乙酰基-2-脱氧-1-N-[2-N-(L-酪氨酸基)-L-天冬酰胺-4-酰基]-β-D-吡喃葡萄糖胺与5-苄基1-对硝基苯基N-(叔丁氧羰基)-L-谷氨酸缩合，随后除去酯基，制备了具有人血浆α1-酸性糖蛋白氨基酸序列10 - 12的糖三肽2-乙酰氨基-1-N-(2-N-[N-(叔丁氧羰基)-L-谷氨酰胺-1-酰基-L-酪氨酸基]-L-天冬酰胺-4-氧基)-2-脱氧-β-D-吡喃葡萄糖胺。
