β-Phenylproline: the high β-turn forming propensity of proline combined with an aromatic side chain
作者:Paola Fatás、Ana I. Jiménez、M. Isabel Calaza、Carlos Cativiela
DOI:10.1039/c1ob06561k
日期:——
pyrrolidine ring is significantly affected by the presence of the aromatic substituent, which tends to occupy positions that minimize steric repulsions. As a consequence, this substituent adopts specific well-defined orientations, which are more restricted for the cis derivative. Interactions between this aromatic group and that in the adjacent phenylalanine residue may be responsible for some of the conformational
已经研究了相对于羰基而言,顺式或反式构型的带有连接至β碳的苯基取代基的脯氨酸类似物的构象倾向。已将顺式和反式(βPh)Pro的行为与顺式和反式(βPh)Pro的行为进行了比较脯氨酸在同手性和异手性二肽序列中。NMR和IR研究以及X射线衍射分析提供了证据,证明β-苯基取代基不会破坏脯氨酸占据β圈的i +1位置。吡咯烷环的褶皱受到芳族取代基的影响,芳族取代基趋于占据使空间排斥最小化的位置。结果,该取代基采用特定的明确定义的方向,该方向对于顺式衍生物更受限制。该芳香基团与相邻的苯丙氨酸残基之间的相互作用可能是所研究的不同肽之间观察到的某些构象差异的原因。