Circular dichroism of ketoprofen complexed to serum albumins: conformational selection by the protein: a novel optical purity determination technique.
Circular dichroism of ketoprofen complexed to serum albumins: conformational selection by the protein: a novel optical purity determination technique.
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酮洛芬与血清白蛋白复合的圆二色性：蛋白质的构象选择：一种新型光学纯度测定技术。
DOI：
10.1002/chir.530070610
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发表时间：
1995
期刊：
影响因子：
2
通讯作者：
M. Zandomeneghi
中科院分区：
文献类型：
--
作者：
M. Zandomeneghi
2-（3 '-苯甲酰基苯基）丙酸（酮洛芬）1与牛血清白蛋白（BSA）的络合导致苯甲酰基苯基部分的酮基n->pi* 带中的强负圆二色性。这种高CD与溶解在普通溶剂中的1-对映异构体的弱CD形成对比。此外，一些含有二苯甲酮部分的手性和非手性分子很容易与BSA络合：所有这些络合物在同一跃迁处显示出强烈的CD。为了解释观察到的上述分子的CD强度，似乎BSA络合显着移动强烈不对称，antipodic构象之间的平衡。这些构象的不对称性与苯环与羰基发色团共面的结构的不稳定性有关，分子力学计算也表明了这一点。由于蛋白质，1-对映体的科顿效应的放大可以用于以优异的精度测量1-样品的光学纯度。与BSA相反，人SA不能识别1-对映体的手性;油酸共络合修饰了这一事实以及结合的其他特征。
Complexation of 2-(3'-benzoylphenyl)propionic acid (ketoprofen), 1, to bovine serum albumin (BSA) results in an intense negative circular dichroism in the ketonic n-->pi* band of the benzoylphenyl moiety. This high CD contrasts with the weak CD of 1-enantiomers dissolved in common solvents. Furthermore, a number of chiral and achiral molecules containing the benzophenone moiety are easily complexed to BSA: all these complexes show an intense CD at the same transition. To account for the observed CD intensities of the above molecules, it appears that BSA complexation markedly shifts the equilibrium between strongly asymmetric, antipodic conformers. Dissymmetry of these conformers is connected to the instability of a structure with phenyl rings coplanar to the carbonyl chromophore, as also indicated by molecular mechanics calculations. The magnification of the Cotton effects of the 1-antipodes, due to the protein, can be used to measure the optical purity of 1-samples with excellent precision. In contrast with BSA, human SA is unable to recognize the chirality of 1-antipodes; oleic acid cocomplexation modifies this fact as well as other features of the binding.