Seryl and threonyl peptides are converted into α-acetoxyglycyl peptides by treatment with lead tetraacetate. Reaction of these acetoxy derivatives or the more reactive α-chloroglycyl peptides with thiols, dithiols and carbohydrates allows the attachment of such units to peptide chains. The reaction of α-chloroglycyl peptides with amino acid esters and enamines proceeds with high stereoselectivity and
通过用四
乙酸铅处理,将丝
氨酰和苏
氨酰肽转化成α-乙酰氧基糖基肽。这些乙酰氧基衍
生物或更具有反应性的α-
氯缩水甘油基肽与
硫醇,二
硫醇和
碳水化合物的反应使得这些单元可以连接到肽链上。α-
氯代糖基肽与
氨基酸酯和烯胺的反应以高的立体选择性进行,并分别产生具有N,N-
乙缩醛和(2-氧代环己基)甘
氨酸部分的肽。