Synthesis, Structure and Conformation of Partially-Modified Retro- and Retro-Inversoψ[NHCH(CF3)]Gly Peptides
作者:Alessandro Volonterio、Stefano Bellosta、Fabio Bravin、Maria Cristina Bellucci、Luca Bruché、Giorgio Colombo、Luciana Malpezzi、Stefania Mazzini、Stefano V. Meille、Massimiliano Meli、Carmen Ramírez de Arellano、Matteo Zanda
DOI:10.1002/chem.200304881
日期:2003.9.22
sp(3) bonds in the [CO-CH(2)-CH(CF(3))-NH-CH(R)-CO] module, which is biased by the stereoelectronically demanding CF(3) group and the R side chain; 2) formation of nine-membered intramolecularly hydrogen-bonded rings, which have been clearly detected both in CHCl(3) solution and in some crystal structures. The former factor seems to be more important, as turn-like conformations were found in the solid-state
psi [NHCH(CF(3))] Gly肽,部分概念修饰的逆肽(PMR)和逆反(PMRI)肽,是一类概念上新型的拟肽,已通过Aza-Michael反应合成了宽结构多样性和可变长度的肽对映体纯的α-氨基酯和对映体和几何纯的N-4,4,4-三氟巴豆酰基-恶唑烷-2-酮。已经研究了观察到的中等到良好非对映控制的基础因素。已通过溶液的MD计算支持(1)H NMR光谱研究了溶液中模型PMR-psi [NHCH(CF(3))] Gly三肽的构象,并通过X射线衍射研究了其固态。可以证明,与亲本基于丙二酰基的逆向肽相比,turn-like构象具有显着的稳定性,这可能是由于以下两个主要因素造成的:1)对[CO-CH(2)-CH(CF(3))-NH-CH(R)-CO]模块中sp(3)键的严格扭转限制,这受立体电子要求的CF(3)的偏见)基团和R侧链;2)形成的九元分子内氢键环,已经清楚地在CHCl(3)溶液