Recyclable Hypervalent Iodine(III) Reagent Iodosodilactone as an Efficient Coupling Reagent for Direct Esterification, Amidation, and Peptide Coupling
作者:Jun Tian、Wen-Chao Gao、Dong-Mei Zhou、Chi Zhang
DOI:10.1021/ol301085v
日期:2012.6.15
hypervalent iodine(III) reagent plays a novel role as an efficient coupling reagent to promote the direct condensation between carboxylicacids and alcohols or amines to provide esters, macrocyclic lactones, amides, as well as peptides without racemization. The regeneration of iodosodilactone (1) can also be readily achieved. The intermediate acyloxyphosphonium ion C from the activation of a carboxylic acid
Amino-acids and peptides. Part XXXIV. Anchimerically assisted coupling reactions: the use of 2-pyridyl thiolesters
作者:K. Lloyd、G. T. Young
DOI:10.1039/j39710002890
日期:——
presented of the use in peptide synthesis of esters for which aminolysis is assisted by a neighbouring group. 2-Pyridylthiolesters of phthaloyl-, benzyloxycarbonyl-, and t-butoxycarbonyl-amino-acids are described, and it is shown that they condense very rapidly even with hindered amino-esters to give high yields of protected dipeptides. Phthaloyl-L-phenylalanine pyrimidin-2-yl thiolester is also described