N-Acetylneuraminic acid (1) was prepared from the salivary gland mucins of the Chinese swiftlet by an improved procedure using acidic resin hydrolysis. Compound 1 was transformed into the known acetochloroneuraminic acid (3) by a new two-step procedure. Koenigs–Knorr glycosylation of 3 followed by subsequent reductive ozonolysis of the 2-propenyl α-glycoside afforded the key aldehyde precursors 7 and 8, which were coupled to bovine serum albumin or tetanus toxoid by reductive amination. The factors influencing the extent of incorporation were investigated. A series of N-acetylneuraminic acid analogues modified at strategic functionalities were also synthesized. Keywords: sialic acid, N-acetylneuraminic acid, neoglycoproteins, bovine serum albumin, tetanus toxoid.
N-乙酰神经酰胺酸(1)是通过改进的程序从中国燕子的唾液腺黏蛋白中制备的,该程序使用酸性树脂水解。化合物1通过新的两步程序转化为已知的乙酰氯乙酰神经酸(3)。对3进行Koenigs-Knorr糖基化,然后通过随后的还原臭氧裂解2-丙烯基α-糖苷制得关键的醛前体7和8,它们通过还原胺化与牛血清白蛋白或破伤风类毒素结合。研究了影响合并程度的因素。还合成了一系列在战略性功能上修改的N-乙酰神经酰胺酸类似物。关键词:唾液酸,N-乙酰神经酰胺酸,新糖蛋白,牛血清白蛋白,破伤风类毒素。