بحث
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

El Sayed H. El Ashry,1,2,* El Sayed H. El Tamany,3 Mohamed R. E. Aly,4 Ahmed T. A. Boraei1
 

Abstract

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 presence of basic alumina gave the S-glycosyl oxadiazoles while in presence of Hg (II) chloride the N-3 glycosyl analogues  were obtained.  In the presence of Et3N or K2CO3, mixtures of S- and N-glycosylated isomers were the products. 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

 






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