112142-83-3Relevant academic research and scientific papers
The Azirine/Oxazolone Method in Peptide Chemistry: Synthesis of Tripeptide Models
Wipf, Peter,Heimgartner, Heinz
, p. 140 - 154 (2007/10/02)
Tripeptides 5, containing an α,α-disubstituted α-amino acid and ethyl p-aminobenzoate, were synthesized in high yield by application of the azirine/oxazolone method (Table 2).In this versatile approach for the incorporation of disubstituted residues into the peptide chain, N-protected peptides or amino acids are coupled with 2,2-dialkyl-3-amino-2H-azirines and, after the selective hydrolysis of the newly formed C-terminal amid bond, further condensed with amino components via in situ generated oxazole-5(4H)-ones in the presence of additives (Scheme 1).A comparison with conventional procedures clearly demonstrates the advantages of this new method that works equally well with β-branched, cyclic, or acyclic disubstituted amino acids.
Selective Amide Cleavage in Peptides Containing α,α-Disubstituted α-Amino Acids
Wipf, Peter,Heimgartner, Heinz
, p. 354 - 368 (2007/10/02)
A new synthesis of dipeptides with terminal α,α-disubstituted α-amino acids, using 2,2-disubstituted 3-amino-2H-azirines 1 as amino-acid equivalents, is demonstrated.The reaction of 1 with N-protected amino acids leads to the corresponding dipeptide amide
