Organylbis-(1-silatranylmethyl)amines

Russian Journal of General Chemistry -     

Crystal and molecular structure of N-(1-silatranylmethyl)phthalimide

By X-ray diffraction the crystal and molecular structure of N-(1-silatranylmethyl)phthalimide (SMP) is determined. The coordination polyhedron of the silicon atom in SMP, as in all silatranes, is a trigonal bipyramide; the phthalimide cycle is planar. The data presented indicate that the silatranylmethyl group almost does not affect the geometry of the phthalimide moiety.     

Crystal and molecular structure of N-(1-silatranylmethyl)benzimidazole

The crystal and molecular structure of N-(1-silatranylmethyl)benzimidazole was established by X-ray diffraction. The coordination polyhedron of the silicon atom in this molecule is a trigonal bipyramid. The bond lengths and angles of the N-(1-silatranylmethyl)benzimidazole (SMBI) molecule are compared with the corresponding values for other derivatives of this heterocycle. The silatranylmethyl group, having a high electron-donor inductive effect, does not increase the total aromaticity of the SMBI molecule.     

光谱法研究黄曲霉毒素B1与人血清白蛋白的结合反应

黄曲霉毒素B1(AFB1)是目前发现的致癌能力最强的真菌毒素,严重危害人畜健康.人血清白蛋白(Human serum albumin,HSA)在结合、运输内源性和外源性等小分子物质方面具有重要的生理功能.研究AFB1与HSA的相互作用机理和作用过程,在分子毒理学上具有重要意义.本研究模拟在人体血液pH条件(pH7.4,离子强度0.1 mol/L),通过荧光淬灭、3D荧光法和圆二色谱(Circular dichroism,CD)等光谱方法研究AFB1与人血清蛋白的相互作用.结果表明,AFB1与HSA的内源荧光淬灭属于静态淬灭,AFB1-HSA在298,303,308和313 K4个温度条件下,结合常数均为104数量级,结合位点都约为l.根据Van't Hoff方程,AFB1-HSA体系是熵增焓减的自发过程,分子间主要作用力为疏水作用和氢键.基于F(o)rster's能量转移,得知AFB1与HSA结合距离为3.31 nm.竞争结合实验表明,AFB1结合在HSA的siteI位点上,靠近色氨酸Trp-214.通过3D荧光分析,AFB1的结合作用导致了HSA氨基酸残基微环境和二级构象发生变化.圆二色谱的分析结果表明,二者的结合使得HSA的α-螺旋含量增加.     

吡虫啉与牛血红蛋白相互作用的光谱研究

利用紫外可见光谱和荧光光谱研究了在生理pH值条件下农药吡虫啉与牛血红蛋白(BHb)的相互作用。实验结果表明:吡虫啉分子与BHb发生反应生成复合物,导致BHb内源荧光的猝灭,该猝灭属于静态猝灭。测定了不同温度下该反应的表观结合常数、结合位点数及结合热力学参数,热力学参数的变化表明上述作用过程是一个熵增加、自由能降低的自发分子间作用过程,吡虫啉与BHb之间以静电和疏水作用力为主;并用同步荧光光谱法探讨了吡虫啉对BHb构象的影响。     

Molecular Spectroscopic Study on the Interaction between Heparin and Neutral Red

The interaction between heparin and neutral red was investigated by molecular spectroscopic methods. The change of all spectra suggested that positively charged neutral red had interacted with negatively charged heparin. The study of influence factors indicated that electrostatic force and hydrophobic bond might be involved in the interaction. The total binding number per disaccharide unit and intrinsic binding constant were obtained using Scatchard model.     

噻嗪酮与牛血清白蛋白相互作用的光谱法研究

用荧光光谱和紫外光谱,在模拟生理条件下研究噻嗪酮与牛血清白蛋白(BSA)的相互作用.研究发现,噻嗪酮与牛血清白蛋白的猝灭机制为静态猝灭;298 K、303 K和308 K时的结合常数分别1.80×103、1.54×103和1.05×103L·moL-1,结合位点数n近似为1;由热力学参数推测噻嗪酮与牛血清白蛋白间结合力...     

Synthesis and molecular structure of cobalt(II) complex with 1-(1-silatranylmethyl)-1,2,4-triazole

Reaction of cobalt chloride with 1-(1-silatranylmethyl)-1,2,4-triazole in benzene afforded complex CoCl₂·2L (L = 1-(1-silatranylmethyl)-1,2,4-triazole). It was isolated as the solvate [CoCl₂·2L]·CH₂Cl₂ (1) by recrystallization from dichloromethane and structurally characterized by single-crystal X-ray diffraction. It crystallizes in the monoclinic space group P2₁/m with a = 6.798(2) E, b = 20.326(5) E, c = 11.005(3) E, and Z = 4. The cobalt atom is in slightly distorted square-planar environment, coordinated to two nitrogen atoms from two ligands and two chloride ions.     

光谱法研究埃洛石纳米管与溶菌酶间的相互作用

以溶菌酶作为模型蛋白,主要利用光谱法研究了埃洛石纳米管与溶菌酶之间的相互作用。荧光光谱结果表明向溶菌酶体系中加入埃洛石纳米管会出现荧光猝灭现象,猝灭机理符合静态猝灭规律。共振光散射强度的增加可能与埃洛石纳米管-溶菌酶复合物的形成而导致的分子尺寸的增加有关,这与紫外-可见吸收光谱的变化和静态猝灭机理相一致。同步荧光光谱分析表明两者之间的相互作用可能发生在色氨酸所处位置附近,作用过程使溶菌酶的二级结构发生变化,分子链错误折叠,加入浓度为100mg/L和200mg/L的埃洛石纳米管时,通过圆二色谱数据计算出分别导致α-螺旋的含量降低3.28%和6.89%。     

Spectroscopic and Molecular Docking Study of the Interaction between Neutral Re(I) Tetrazolate Complexes and Bovine Serum Albumin

Re(I) complexes have potential in biomedical sciences as imaging agents, diagnostics and therapeutics. Thus, it is crucial to understand how Re(I) complexes interact with carrier proteins, like serum albumins. Here, two neutral Re(I) complexes were used (fac-[Re(CO)₃(1,10-phenanthroline)L], in which L is either 4-cyanophenyltetrazolate (1) or 4-methoxycarbonylphenyltetrazole ester (2) , to study the interactions with bovine serum albumin (BSA). Spectroscopic measurements, calculations of thermodynamic and Förster resonance energy transfer parameters, as well as molecular modelling, were performed to study differential binding between BSA and complex 1 and 2 . Induced-fit docking combined with quantum-polarised ligand docking were employed in what is believed to be a first for a Re(I) complex as a ligand for BSA. Our findings provide a basis for other molecular interaction studies and suggest that subtle functional group alterations at the terminal region of the Re(I) complex have a significant impact on the ability of this class of compounds to interact with BSA.     

中草药功能因子山柰酚与DNA相互作用的研究

在生理酸度条件下(pH=7.4),运用紫外-可见、粘度、DNA熔点效应及以中性红(NR)为荧光探针的同步荧光等实验手段研究了山柰酚与DNA的相互作用.结果表明:加入DNA后,山柰酚的吸收光谱呈现减色和红移现象;山柰酚的加入使得DNA-NR同步荧光强度猝灭,表明山柰酚对NR与DNA的结合为竞争性抑制;山柰酚的加入使得DNA的粘度增大,热变性温度升高.由上述实验现象推断山柰酚与DNA之间发生了嵌插作用.计算了25、32和39 ℃下,山柰酚与DNA相互作用的结合常数K和结合位点数n分别为3.87×103 L·mol-1、0.85,6.71×103 L·mol-1、0.92和9.73×103 L·mol-1、0.92.由求得的热力学参数推断山柰酚与DNA结合的驱动力主要是疏水作用力.     

Interaction mechanisms between poly(amido‐amine) and nano‐silicon dioxide

To gain insight into the attachment of ?Si⁺ (SC) and ?SiO^? (SOA) ions (regarded as guests) to the lowest generation, ? NH₂‐terminated poly(amidoamine) (PAMAM) dendrimers (regarded as host) in the gas phase, density functional theory is used to investigate the structures and energetics of the complexes with B3LYP/6‐31+G (d) and HF/6‐31G basis sets. The initial parameters are obtained through the initial optimizations at the HF level using the most basic STO‐3G basis set. Various initial configurations of the ions bound to PAMAM are tested, and four stable conformers are found, i.e., types A to D. Types 1A and 2C are the most stable due to the chemical bond formations of Si? N° and Si? O, respectively. For type B, SC coordination to amide O sites occurs via electrostatic induction. For type D, SOA coordination to amide hydrogen and amine hydrogen sites occurs via hydrogen bond interaction. Spatial hindrance, electrostatic induction force, and hydrogen‐bond interaction play important roles in the complexation process. © 2013 Wiley Periodicals, Inc. This article was published online on 5 July 2012. An error was subsequently identified. This notice is included in the online and print version to indicate that both have been corrected on 3 August 2012.     

光谱法研究根皮苷与人血清白蛋白相互作用

在模拟生理条件下,采用荧光光谱、紫外光谱和同步荧光光谱法研究了根皮苷(Phlorizin)与人血清白蛋白(HSA)的相互作用。结果表明:根皮苷能使HSA发生内源荧光猝灭,属静态猝灭。在293、303 K和313 K下,根皮苷与HSA的结合常数分别为3.163 5×105、1.774 8×105、1.193 5×105L.mol-1,结合位点数n近似为1;热力学分析表明根皮苷与HSA间的结合力为氢键及范德华力;根据Frster非辐射能量转移理论求得二者结合距离为3.97 nm;同步荧光光谱表明根皮苷主要与HSA中的色氨酸残基发生相互作用,改变色氨酸周围的局部构象;金属离子的介入会影响根皮苷与HSA的结合能力。     

甘草酸二铵与牛血清白蛋白相互作用的光谱

在模拟人体生理条件下,用常规荧光光谱和紫外－可见吸收光谱研究甘草酸二铵和牛血清白蛋白的相互作用机制,并利用同步荧光光谱和三维荧光光谱研究了药物对牛血清白蛋白构象的影响。研究表明,甘草酸二铵对牛血清白蛋白具有荧光猝灭作用,且为单一的动态猝灭过程。根据Stern-Volmer方程求出了两者相互作用的动态猝灭常数,并根据Förster非辐射能量转移理论确定了药物与蛋白的结合距离。     

Crystal structure of silicon organic compounds. I. Triphenyl-(1-silatranylmethyl) phosphonium iodide

For Communication 60 see [1].     

Spectroscopic Study of the Interaction between New Fluorescent Dyes with Nucleic Acids

Considerableefforthasbeencofltinuingtofocusonthedevelopmentofnewfluorescentdyestorecognizenucleicacids'-'.Althoughdansylisawell-knownsensitivehydrophobicprobewhichhasbeenwidelyutilizedasafluorescentprobeforthestudyofproteins,yetlittleefforthasbeenfocusedontheexploringdansylamidederivativeswhichmayhavespecificeffectsonnucleicacids.Sincethebindingaffinityofsuchfluorophorestopolynucleotideswasgreatlyaffectedbytheirsidechainsubstitutions,inthisworkseveralnewdansylderivativeswithspecificbindingtonu…     

表柔比星-铜体系与DNA作用的光谱和电化学法研究

表柔比星是临床上广泛用于治疗增殖很快的肿瘤. 应用紫外、荧光、黏度、循环伏安等方法研究了表柔比星及表柔比星-Cu^2＋体系与DNA的作用. 结果发现: 在pH＝7.4时, 表柔比星可与Cu^2＋形成稳定体系. 加入DNA后表柔比星-Cu^2＋体系的紫外吸收明显降低; Scatchard图表明表柔比星-Cu^2＋体系对溴化乙锭(EB)与DNA的结合为竞争性抑制; 同时此体系可使DNA-EB体系荧光偏振度增大; 使DNA的热变性温度(t_m)上升; 黏度增大; 循环伏安法表明DNA的加入使得表柔比星及表柔比星-Cu^2＋体系的式量电位正移; 凝胶电泳表明表柔比星-Cu^2＋体系对pBR322 DNA有非常好的水解切割活性. 综合以上结果得出: 表柔比星及表柔比星-Cu^2＋体系与DNA之间均为嵌插作用; 表柔比星-Cu^2＋体系具有更好的水解切割活性. 这些结果可为合理改善药效、降低抗癌药物毒性和设计新药提供依据.