An improved approach for the synthesis of α,α-dialkyl glycine derivatives by the Ugi–Passerini reactionElectronic supplementary information (ESI) available: spectroscopic data for compounds 1-5. See http://www.rsc.org/suppdata/ob/b2/b212473b/
An improved approach for the synthesis of α,α-dialkyl glycine derivatives by the Ugi–Passerini reactionElectronic supplementary information (ESI) available: spectroscopic data for compounds 1-5. See http://www.rsc.org/suppdata/ob/b2/b212473b/
Synthesis of N-acyl-N,α,α-trialkyl and N-acyl-α,α-dialkyl glycines by selective cleavage of Ugi–Passerini adducts. Qualitative assessment of the effect of substituents on the path and yield of reaction
作者:Wei-Qun Jiang、Susana P. G. Costa、Hernâni L. S. Maia
DOI:10.1039/b307111c
日期:——
symmetric N-acyl-N,alpha,alpha-trialkyl glycine amides were synthesised by the Ugi-Passerini four-component reaction and subjected to selective cleavage with trifluoroacetic acid. In almost all cases it was possible to obtain the corresponding N-acyl-N,alpha,alpha-trialkyl and N-acyl-alpha,alpha-dialkyl glycines in fair to good yields directly from the reaction adducts. With some of the bulkier compounds
An improved approach for the synthesis of α,α-dialkyl glycine derivatives by the Ugi–Passerini reactionElectronic supplementary information (ESI) available: spectroscopic data for compounds 1-5. See http://www.rsc.org/suppdata/ob/b2/b212473b/
作者:Susana P. G. Costa、Hernâni L. S. Maia、Sílvia M. M. A. Pereira-Lima
DOI:10.1039/b212473b
日期:2003.4.23
A general and simple strategy for routine peptide synthesis with α,α-dialkyl glycines taking advantage of the four-component UgiâPasserini reaction is presented. The isonitrile required for the reaction can be relatively simple and its selection based on cost, as the group it generates is easily removed under acidic conditions; in addition, this removal is not visibly affected by the bulkiness of the α-alkyl groups. Being a good leaving group from the N-terminal amino group of the amino acid, 4-methoxybenzyl was the choice for the amine component of the reaction. The method is illustrated with the synthesis of a series of acyl derivatives of several α,α-dialkyl glycines. The preparation of the latter compounds is also reported.