α-Amino acid derived enaminones and their application in the synthesis of N-protected methyl 5-substituted-4-hydroxypyrrole-3-carboxylates and other heterocycles
作者:Uroš Grošelj、Mojca Žorž、Amalija Golobič、Branko Stanovnik、Jurij Svete
DOI:10.1016/j.tet.2013.11.008
日期:2013.12
simple synthesis of novel N-protected methyl 5-substituted-4-hydroxypyrrole-3-carboxylates, which exist in equilibrium with their 4-oxo tautomers, has been developed in two steps starting from N-protected α-amino acids. The key intermediates are enaminones, which can also be isolated, characterized, and used for the construction of other functionalized heterocycles, before they spontaneously decompose
Amino Acids and Peptides; 67.<sup>1</sup>Easy Preparation and Use of Benzyloxycarbonyl Derivatives of Amino Acid Chlorides and α-Hydroxycarboxylic Acid Chlorides
作者:Ulrich Schmidt、Matthias Kroner、Ulrich Beutler
DOI:10.1055/s-1988-27612
日期:——
N-Benzyloxycarbonyl amino acid chlorides and α-benzyloxycarbonyloxy carboxylic acid chlorides are readily available by treating the corresponding carboxylic acids with 1-chloro-N,N,2-trimethyl-1-propen-1-amine. They can be immediately reacted with O-, N- and C-nucleophiles to afford peptides, ketones and esters.