75830-38-5Relevant academic research and scientific papers
Direct peptide coupling of novel amino acid derivatives produced by rearrangement of catalytically generated ammonium ylides
Clark, J. Stephen,Middleton, Mark D.
, p. 7031 - 7034 (2007/10/03)
Protected amino acids can be prepared from substrates in which a diazo ester is aryl-tethered to an allylic amine, by catalytic intramolecular ammonium ylide generation and [2,3] rearrangement. When the aryl tether is sufficiently electron-deficient, direct coupling of the rearrangement product with a hindered amino acid ester to give a dipeptide is possible, and ammonium ylide generation, rearrangement and peptide coupling can be accomplished in a one-pot fashion.
Intramolecular O,N-Acyl Transfer via Cyclic Intermediates of Nine and Twelve Members. Models for Extensions of the Amine Capture Strategy for Peptide Synthesis
Kemp, D. S.,Kerkman, Daniel J.,Leung, See-Lap,Hanson, Gunnar
, p. 490 - 498 (2007/10/02)
Rate constants are reported for intramolecular O,N-acyl-transfer reactions of 2-amino-N-benzyl-N-acetamides,2-amino-N-benzyl-N-(4-acetoxy-5-xanthyl)methylene>acetamide, ethyl N-(2-acetoxybenzyl)-2-aminoacetate, methyl N--2-aminoacetate and their alanine and valine analogues in acetonitrile, Me2SO, and other solvents.Synthesis of these substrates is described, and a novel two-step synthesis is reported of 4-hydroxy-5-formylxanthene from 2,3-diacetoxybenzaldehyde and 2-(isopropoxymethylene)cyclohexanon in 29percent yield.Facile intramolecular acyl transfer via cyclic intermediates of 9 and 12 members is described, and steric and solvent effects on rates of acyl transfer are reported for these processes and compared with those for other intra- and intermolecular acyl-transfer reactions.The significance of these results for amide formation by amine capture is discussed.
