Polypeptides. Part XIII. The use of β-methylthioethyl esters for the protection of carboxyl groups in peptide synthesis
作者:M. Joaquina S. A. Amaral、G. C. Barrett、H. N. Rydon、J. E. Willett
DOI:10.1039/j39660000807
日期:——
methiodides and sulphones derivedfrom the β-methylthioethyl esters of amino-acids and peptides are split to the parent carboxylic acids under extremely mild alkaline conditions. Methods for the preparation of β-methylthioethyl esters of amino-acids are described and their use in peptide synthesis is explored. The β-methylthioethyl ester group is advocated as a useful new carboxyl protecting group
Simple Generation of Nonstabilized Azomethine Ylides through Decarboxylative Condensation of α-Amino Acids with Carbonyl Compounds via 5-Oxazolidinone Intermediates
Heating α-amino acids with a variety of carbonyl compounds generates N-unsubstituted or N-substituted azomethine ylides of nonstabilized types through the elimination of water and carbon dioxide. The ylides are captured by olefinic, acetylenic, and carbonyl dipolarophiles producing pyrrolidines, pyrrolines, and oxazolidines. The reaction involves intermediary 5-oxazolidinones which can be sometimes