Faculty of Chemistry, Jagiellonian University, Gronostajowa 2, Krakow 30-387, Poland.
Jagiellonian Centre for Experimental Therapeutics (JCET), Jagiellonian University, Bobrzynskiego 14, Krakow 30-348, Poland.
J Phys Chem Lett. 2020 Jul 2;11(13):5037-5043. doi: 10.1021/acs.jpclett.0c01218. Epub 2020 Jun 16.
In this work, cobalamins with different upper axial substituents and a cobalamin derivative with a ring modification were studied using chiroptical spectroscopies, in particular resonance Raman optical activity (RROA), to shed light on the influence of structural modifications on RROA spectra in these strongly chiral systems in resonance with multiple excited states at 532 nm excitation. We have demonstrated that for these unique systems RROA possesses augmented structural specificity, surpassing resonance Raman spectroscopy and enabling at the same time measurement of cobalamins at fairy low concentrations of ∼10 mol dm. The enhanced structural specificity of RROA is a result of bisignate spectra due to resonance via more than one electronic state. The observation of increased structural capability of RROA for cobalamins opens a new perspective for studying chiral properties of other biological systems incorporating d-metal ions.
在这项工作中，使用手性光谱学，特别是共振拉曼圆二色性（RROA），研究了具有不同上轴向取代基的钴胺素和具有环修饰的钴胺素衍生物，以阐明结构修饰对这些在 532nm 激发下与多个激发态共振的强手性体系中 RROA 光谱的影响。我们已经证明，对于这些独特的体系，RROA 具有增强的结构特异性，超过了共振拉曼光谱，同时能够以低至约 10mol dm 的浓度测量钴胺素。RROA 的增强结构特异性是由于通过不止一个电子态共振产生的双信号光谱的结果。RROA 对钴胺素的结构能力的增加的观察为研究包含 d 金属离子的其他生物体系的手性性质开辟了新的视角。
