RESUMO
[structure: see text]. Syntheses of the two benzo derivatives of HOAt are described. Conversion of the two isomers to the corresponding onium-style coupling reagents gave in one case a guandinium species 14 and in the other, presumably as a result of steric factors, a uronium species 15. The two systems are compared as to their effectiveness in peptide coupling processes.
Assuntos
Compostos Aza/síntese química , Triazóis/química , Triazóis/síntese química , Compostos Aza/química , Peptídeos/química , Isoformas de ProteínasRESUMO
The guanidine moiety is an important motif present in many biologically active compounds. Fully substituted guanidines are of key importance for the development of bioactive molecules. The present paper reports on an efficient procedure for the direct solid-phase conversion of amines to fully substituted guanidines under very mild conditions.
Assuntos
Guanidinas/síntese química , Cromatografia Líquida de Alta Pressão , Técnicas de Química Combinatória , Guanidinas/química , Indicadores e Reagentes , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por MatrizRESUMO
Synthesis of 5- and 6-HOAt has completed the full set of the four HOAt isomers derived from HOBt by insertion of a single nitrogen atom in the benzenoid nucleus. Comparison of the reactivity of all four isomers in model peptide coupling reactions has confirmed the unique character of the 7-isomer in promoting selectivity and maintaining configuration at the reactive carboxylic acid residue.