Transition State Analogy of Phosphonic Acid Peptide Inhibitors of Pepsin
摘要:
A series of 11 phosphonate peptide analogs, RO(2)C-Xaa-Yaa-Phe-(PO2--O)-Phe O-(3-(4-pyridyl)propyl ester), were synthesized and evaluated as inhibitors of the aspartic peptidase pepsin. For the inhibitors with Gly or Ala at the P-2 position, the K-i values correlate with the K-m/k(cat) values of the corresponding substrates, demonstrating that these analogs mimic the transition state in the way the P-2-P-4 residues bind. Deviations from the correlation for the other inhibitor/substrate pairs imply a different binding orientation as a result of N-substitution at P-2 (Pro), contamination with the more potent diastereomer (D-Ala), or a change in rate-limiting step for turnover (lie).
Peptide synthesis using the four-component condensation (Ugi reaction)
作者:Michinori Waki、Johannes Meienhofer
DOI:10.1021/ja00460a039
日期:1977.8
permit solution synthesis’ of homogeneous peptides with up to 50 amino acid residues2 but condensation of peptides of this size to obtain proteins with over 100 residues has not yet progressed beyond the pioneering stage. The remarkable ribonuclease S-protein synthesis by Hirschmann et al.3 remains to be as yet the only preparation of a peptide of over 100 residues. This synthesis underscored the problem