Chemoenzymatic synthesis of Gal(β1-3)Gal(β1-4)Xyl(β)-l-Ser and Gal(β1-3)Gal(β1-4)Xyl(β)-MU by the use of β-d-galactosidase
作者:Koichi Fukase、Takashi Yasukochi、Yasuo Suda、Masao Yoshida、Shoichi Kusumoto
DOI:10.1016/s0040-4039(96)01462-1
日期:1996.9
protein in proteoglycan, was synthesized via a trisaccharide p-nitrophenyl (PNP) glycoside prepared by stepwise enzymatic transglycosidation to Xyl-PNP with a β-d-galactosidase. In the second transglycosidation step, partial protection of the disaccharide intermediate, Gal-Xyl-PNP, furnished selective galactosylation at the 3′-position. Cleavage of the PNP group after peracetylation, chemical coupling
通过三糖对硝基苯基(PNP)糖苷合成蛋白质,该蛋白构成糖胺聚糖和蛋白聚糖中蛋白质之间的连接区域的标题三糖-丝氨酸缀合物1,该三糖对硝基苯基(PNP)糖苷是用β-d-半乳糖苷酶逐步酶促糖基化为Xyl-PNP制备的。在第二个糖基转移步骤中,对二糖中间体Gal-Xyl-PNP的部分保护提供了在3'-位的选择性半乳糖基化。过乙酰化后,PNP基团的裂解,与丝氨酸的化学偶联和最终的脱保护得到1。荧光标记的三糖,Gal(β1-3)Gal(β1-4)Xyl(β)-MU(MU:4-methylumbelliferyl)(2)也以类似的方式合成。