College of Chemistry, Xiangtan University, Xiangtan, 411105, People's Republic of China.
Academic Affairs Office, Xiangtan University, Xiangtan, 411105, People's Republic of China.
J Biol Inorg Chem. 2023 Aug;28(5):509-517. doi: 10.1007/s00775-023-02004-2. Epub 2023 Jul 15.
Two chiral ruthenium(II) polypyridyl complexes, Λ-[Ru(bpy)(dppx)] (bpy = 2,2'-bipyridine, dppx = 7,8-dimethyldipyridophenazine; Λ-1) and Δ-[Ru(bpy)(dppx)] (Δ-1) have been synthesized and characterized in this work. Interactions of Λ-1 and Δ-1 with the RNA triplex poly(U)⋅poly(A)*poly(U) have been investigated by various biophysical techniques. Spectrophotometric titrations and viscosity measurements suggested that enantiomers Λ-1 and Δ-1 bind with the triplex through intercalation, while the binding strengths of the two enantiomers toward the triplex differed only slightly from each other. Fluorescence titrations showed that although enantiomers Λ-1 and Δ-1 exhibited molecular "light switch" effects toward the triplex, the effect of Δ-1 was more marked. Furthermore, Furthermore, thermal denaturation showed that the two enantiomers have significantly different stabilizing effects on the triplex. The obtained results indicate that the racemic complex [Ru(bpy)(dppx)] is similar to a non-specific metallointercalator for the triplex investigated in this study, and chiralities of Ru(II) polypyridine complexes have an important influence on the binding and stabilizing effects of enantiomers toward the triplex. Two chiral ruthenium(II) polypyridyl complexes, Λ-[Ru(bpy)(dppx)] (bpy = 2,2'-bipyridine, dppx = 7,8-dimethyldipyridophenazine; Λ-1) and Δ-[Ru(bpy)(dppx)] (Δ-1) have been synthesized and characterized in this work. Interactions of Λ-1 and Δ-1 with the RNA triplex poly(U)⋅poly(A)*poly(U) have been investigated by various biophysical techniques. The obtained results indicate that the racemic complex [Ru(bpy)(dppx)] is similar as a non-specific metallointercalator for the triplex investigated in this study, and chiralities of Ru(II) polypyridine complexes have an important influence on the binding and stabilizing effects of enantiomers toward the triplex.
本文合成并表征了两种手性钌（II）多吡啶配合物，Λ-[Ru(bpy)(dppx)]（bpy=2,2'-联吡啶，dppx=7,8-二甲基二吡啶并[3,2-a:2',3'-c]吩嗪；Λ-1）和Δ-[Ru(bpy)(dppx)]（Δ-1）。通过各种生物物理技术研究了 Λ-1 和 Δ-1 与 RNA 三聚体 poly(U)⋅poly(A)*poly(U)的相互作用。分光光度滴定和粘度测量表明，对映异构体 Λ-1 和 Δ-1 通过嵌入与三聚体结合，而两种对映异构体与三聚体的结合强度彼此略有不同。荧光滴定表明，尽管对映异构体 Λ-1 和 Δ-1 对三聚体表现出分子“光开关”效应，但 Δ-1 的效果更为明显。此外，热变性表明，两种对映异构体对三聚体具有显著不同的稳定作用。实验结果表明，外消旋配合物[Ru(bpy)(dppx)]类似于本研究中所研究的三聚体的非特异性金属嵌入剂，并且 Ru(II)多吡啶配合物的手性对映异构体与三聚体的结合和稳定作用有重要影响。
