The role of the Cl- anion as a templating agent for the synthesis of cyclopeptides was assessed through the preparation of three new homocyclolysines and other six cyclic peptides by head-to-tail lactamization. Isolated yields of products obtained by chloride-templating approach were considerably higher than those gained by a cation-promoted procedure, whereby, in some cases, only the anion-assisted synthesis yielded the desired cyclopeptides.
A Selective Electrocatalytic Cleavage of the Benzyloxycarbonyl Group from Peptides
作者:M. Antonietta Casadei、D. Pletcher
DOI:10.1055/s-1987-28191
日期:——
An electrosynthetic procedure for the cleavage of the benzyloxycarbonyl group from protected amino acids and peptides is described. It is based on the use of a high surface area palladium cathode in methanol/acetic acid and gives an excellent selectivity under very mild conditions.
Mechanism study on the Oligomerization of Amino Acids into Peptides by Phosphorus Trichloride
作者:Wenjie Zhao、Dongxin Zhao、Kui Lu
DOI:10.1080/10426500701807467
日期:2008.1.14
As treated by phosphorustrichloride, amino acids could oligomerize into polypeptides. Based on the results obtained by 31P-NMR and ESI-MS/MS, a possible reaction mechanism was proposed. The mechanism might undergo a penta-coordinated phosphorus intermediat. The activated amino acid was a five-membered cyclic penta-coordinated phosphorus intermediate. The nucleophilic attack of the amino group from