N-2-Glycosyl Thiosemicarbazides from N-3-Glycosyl Oxadiazolinethiones Obtained from 2-S-Glycosyl Oxadiazolines via Mild Thermal S→N Migration of the Glycosyl Moiety
作者:El Sayed El Ashry、El Sayed El Tamany、Mohamed Aly、Ahmed Boraei
DOI:10.1055/s-0030-1258024
日期:2010.9
A new class of N-2-glycosyl thiosemicarbazides has been synthesized from N-3-glycosyl oxadiazoline-thiones. Glycosylation of 5-(1H-indol-2-yl)-1,3,4-oxadiazolin-2(3H)-thione with acetylated α-glycosyl halides by grinding in the presence of basic alumina gave the S-glycosyl oxadiazoles while in the presence of Hg(II) chloride N-3 glycosyl analogues were obtained. In the presence of Et3N or K2CO3, mixtures of S- and N-glycosylated isomers were obtained as products. The S→N glycosyl migration under catalyst-free mild thermal conditions was described, and a new class of N-2-glycosyl thiosemicarbazides was synthesized from N-3-glycosyl oxadiazolinethiones by ring cleavage of the oxadiazolole ring by treatment with ammonia in methanol.
一种新的N-2-糖基硫代氨基甲酰肼类化合物由N-3-糖基恶二唑啉硫酮合成。在碱性氧化铝存在下,通过研磨将5-(1H-吲哚-2-基)-1,3,4-恶二唑啉-2(3H)-硫酮与乙酰化的β-糖基卤化物进行糖基化,得到S-糖基恶二唑啉,而在氯化汞(II)存在下则得到N-3糖基类似物。在乙基三乙胺或碳酸钾存在下,得到S-和N-糖基化异构体的混合物作为产物。描述了在无催化剂的温和热条件下S→N糖基迁移,并通过在甲醇中用氨处理来环裂解恶二唑啉环,从N-3-糖基恶二唑啉硫酮合成了一种新的N-2-糖基硫代氨基甲酰肼类化合物。