Characterization of “Mini-Nucleotides” as P2X Receptor Agonists in Rat Cardiomyocyte Cultures. An Integrated Synthetic, Biochemical, and Theoretical Study
作者:Bilha Fischer、Revital Yefidoff、Dan T. Major、Irit Rutman-Halili、Valadimir Shneyvays、Tova Zinman、Kenneth A. Jacobson、Asher Shainberg
DOI:10.1021/jm990085i
日期:1999.7.1
The design and synthesis of "mini-nucleotides", based on a xanthine-alkyl phosphate scaffold, are described. The physiological effects of the new compounds were evaluated in rat cardiac cell culture regarding Ca(2+) elevation and contractility. The results indicate biochemical and physiological profiles similar to those of ATP, although at higher concentrations. The biological target molecules of these
描述了基于黄嘌呤-烷基磷酸支架的“小核苷酸”的设计和合成。在大鼠心肌细胞培养物中评估了新化合物对 Ca(2+) 升高和收缩力的生理作用。结果表明,生化和生理特征与 ATP 相似,但浓度较高。通过使用选择性P2-R和A(1)-R拮抗剂以及P2-R亚型选择性激动剂来鉴定这些“小核苷酸”的生物学靶分子。根据这些结果以及在不含 Ca(2+) 的培养基中进行的实验(其中未观察到 [Ca(2+)](i) 升高),我们得出结论,类似物可能与 P2X 受体亚型发生相互作用,这导致 Ca(2+) 内流。在量子力学水平的简化模型上进行了分析黄嘌呤烷基磷酸酯系列内的电子效应的理论计算。计算出的偶极矩向量、静电势图和体积参数对合成衍生物的活性或不活性提出了解释,并预测了活性激动剂的假定结合位点环境。黄嘌呤-烷基磷酸类似物被证明是激活 P2X-R 亚型的选择性试剂,而 ATP 则激活心肌细胞中的所有 P2-R 亚型。因此,这些类似物可以作为针对
Microflowers formed by complexation-driven self-assembly between palladium(<scp>ii</scp>) and bis-theophyllines: immortal catalyst for C–C cross-coupling reactions
作者:Katsuya Kaikake、Naoki Jou、Go Shitara、Ren-Hua Jin
DOI:10.1039/d1ra06177a
日期:——
quantitatively the reaction of aryl bromides and phenylboronic acid in aqueousmedia at room temperature. It was found that the reaction proceeds better in an air atmosphere than in nitrogen gas even though the Pd(II) species employed was lowered to 0.001 mol% in the substance. Very interestingly, the microflowers could be recycled 20 times without deactivation in the C–C couplingreaction between bromobenzene
With the aim to improve the design of metal complexes as stabilizers of noncanonical DNA secondary structures, namely, G-quadruplexes (G4s), a series of cyclic dinuclear Au(I) N-heterocyclic carbene complexes based on xanthine and benzimidazole ligands has been synthesized and characterized by various methods, including X-ray diffraction. Fluorescence resonance energy transfer (FRET) and CD DNA melting
为了改进作为非经典 DNA 二级结构稳定剂的金属配合物的设计,即 G-四链体 (G4s),合成了一系列基于黄嘌呤和苯并咪唑配体的环状双核 Au(I) N-杂环卡宾配合物并通过各种方法表征,包括 X 射线衍射。荧光共振能量转移 (FRET) 和 CD DNA 熔解分析揭示了化合物对具有不同生理相关拓扑结构的 G4 的稳定特性。初始结构-活性关系已经确定,并将黄嘌呤衍生物家族识别为对 G4 比双链 DNA 更具选择性的那些。最活跃的黄嘌呤衍生物(具有丙基接头)与启动子序列cKIT1的结合模式和自由能景观已被元动力学研究。原子模拟证明 Au(I) 化合物与顶部 G4 四分体非共价相互作用。Au(I) 复合物/DNA 吉布斯结合自由能的理论结果通过 FRET DNA 熔解分析进行了实验验证。这些化合物还在体外测试了它们在人类癌细胞中的抗增殖特性,显示出通常适中的活性。这项研究提供了对 Au(I)