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1.
The structure of mono- and di-ArHg-derivatives of alizarin (1,2-dihydroxy-9,10-anthraquinone) and their interactions with halide- and oxygen-containing salts are examined by vibrational and electronic spectroscopy. The interaction of solid mono- and di-ArHg-derivatives of alizarin with bromides results only in the formation of the monoanion or the ion pair, depending on the nature of the counterion. Dianions are formed in a DMSO solution with very great excess of the bromide.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 11, pp. 2019–2023, November, 1994.The work is performed within the framework of the Direction No 02-05-01 of the Ministry of Science and Technical Policy of Russian Federation. The authors are grateful to the International Science Foundation (grant MHW000) and the Russian Foundation for Basic Research (Project No. 94-03-08873) for financial support.  相似文献   

2.
The mercury derivatives of primary nitramines were proved by molecular spectroscopy and quantum-chemical calculations to be covalent compounds. The mercury atom was found to be coordinated to the amine nitrogen atom.  相似文献   

3.
The visualization of solid-state reactions of bis-O-metallated phenolphthaleins and xylenolphthaleins (M=HgC6H4OMe, AuPPh3) with bromides, which has been discovered for the first time, was studied by IR and electronic reflectance spectroscopy. The appearance of intense coloration (purple, violet, or blue) after short-term grinding of colorless or faintly colored solid samples with salts is due to their ionization with the formation of ion pairs or dianions depending on the nature of the counterion. The reaction affects only a small fraction of the molecules in the surface layers of the metallocomplexes.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 12, pp. 2115–2117, December, 1993.  相似文献   

4.
A series of divalent transition metal phosphonates containing hydrogen-bonded layers of phosphonate anions, namely [M(phen)3]·C6H5PO3·11H2O [M=Co(1), Ni(2), Cu(3)] and [Cd(phen)3]·C6H5PO3H·Cl·7H2O (4) have been synthesized, structurally characterized by single-crystal X-ray diffraction method. These compounds all crystallize in the triclinic system, space group P-1. The lattice parameters are a=12.1646(5), b=12.4155(6), c=15.4117(10) Å, α=78.216(2), β=79.735(3), γ=77.8380(3)°, V=2205.1(2) Å3, Z=2 for 1; a=12.097(2), b=12.606(3), c=15.742(3) Å, α=76.66(3), β=80.04(3), γ=77.75(3)°, V=2263.4(8) Å3, Z=2 for 2; a=12.058(2), b=12.518(3), c=15.781(3) Å, α=77.77(3), β=80.02(3), γ=77.91(3)°, V=2255.5(8) Å3, Z=2 for 3 and a=12.47680(10), b=12.6693(2), c=16.1504(3) Å, α=82.600(1), β=71.122(1), γ=77.355(1)°, V=2352.37(6) Å3, Z=2 for 4. All structures are refined by full-matrix least-squares methods [for 1, R1=0.0602 using 6458 independent reflections with I>2σ(I); for 2, R1=0.0632 using 4657 independent reflections with I>2σ(I); for 3, R1=0.0634 using 6221 independent reflections with I>2σ(I); for 4, R1=0.0400 using 7930 independent reflections with I>2σ(I)]. In the crystal structures, the phenylphosphonate anions and water molecules are hydrogen-bonded to form layers, and there exist the cationic species [M(phen)3]2+ between the adjacent layers of anions and water. Luminescence, thermal analysis as well as IR spectroscopic studies are also presented.  相似文献   

5.
The molecular and crystal structures of 4-acetamido-2,3-dimethyl-1-phenylpyrazol-5-one (1) and 4-maleylamido-2,3-dimethyl-l-phenylpyrazol-5-one (2) were studied. The molecular conformations are stabilizedvia systems of intermolecular hydrogen bonds between the amide groups and the carbonyl oxygen atoms of the pyrazolone rings. The conformation of compound 2 is additionally stabilizediva an intramolecular interaction between the carboxyl group and the amide oxygen atom. According to the IR spectral data, protonation of the compounds under study in an acetonitrile solution occurs at the carbonyl oxygen atom of the pyrazolone ring, which is also confirmed by the UV spectral data. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 7, pp. 1286–1292, July, 1999.  相似文献   

6.
The reaction of 2,4,7-trinitro-9,10-phenanthrenequinone with CuCl in aqueous dimethylformamide or dimethyl sulfoxide at room temperature, followed by acidification, gave a stable red complex of 2,4,7-trinitro-9,10-dihydroxyphenanthrene with a solvent molecule. On heating in a polar aprotic solvent in the presence of CuCl or other metal salt, 2,4,7-trinitro-9,10-phenanthrenequinone underwent benzilic acid rearrangement with formation of 2,4,7-trinitrofluorenone. The nitration of 9,10-sulfuryldioxyphenanthrene and subsequent decomposition of cyclic sulfates afforded previously unknown 1,3,6-trinitro- and 1,8-dinitro-9,10-phenanthrenequinones.  相似文献   

7.
Phenanthrenequinone monoxime and its mono-, di-, and trinitro derivatives were synthesized. The acidity constants and their variation with the number and position of nitro groups were determined. The electronic and IR spectra of the nitro compounds were studied. The bands in the electronic spectra were assigned based on quantum-chemical calculations in the Pariser—Parr—Pople approximation. Correlations between the pK a values and some calculated characteristics of the compounds under study were found. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 6, pp. 1106–1110, June, 1999.  相似文献   

8.
9.
The structural and electronic properties of hydroxyanthraquinone derivatives in rhubarb, namely, chrysophanol, emodin, physcion, aloe‐emodin, rhein, and their radicals were investigated at density functional level. The bifurcated hydrogen bond property of the studied structures was investigated using the atoms in molecules theory. It turned out that the presence of the dihydroxy functionality increases the radical stability through hydrogen bonds formation and favors hydrogen atom abstraction. Bond dissociation energy and ionization potential were also determined to know if the radical scavenging activity of these compounds proceeds via an H‐atom or an electron‐transfer mechanism. © 2010 Wiley Periodicals, Inc. Int J Quantum Chem, 2011  相似文献   

10.
9,10-Diphenylanthracene (DPA), a well-studied organic chromophore (Phi(fl) = 0.98) that exhibits electroluminescence, has been covalently bound through 2-(ethylthio)ethylamido linkers to the carboxylic acid groups of short, soluble single-walled carbon nanotubes (sSWNTs) of 1 microm average length, and the resulting DPA-functionalised sSWNT (DPA- sSWNT) macromolecular adducts (4.6 wt % DPA content) characterised by solution (1)H NMR, Raman and IR spectroscopy and thermogravimetric analysis. Comparison of the quenching of DPA fluorescence (steady-state and time-resolved) and of the transient optical spectra of sSWNTs and DPA-sSWNTs show that the covalent linkage boosts the interaction between the DPA and the sSWNT units. DPA-sSWNTs exhibit emission in the near-IR region from 1100-1400 nm with an enhanced quantum yield (Phi = 5.7x10(-3)) compared with sSWNTs (Phi = 3.9x10(-3)).  相似文献   

11.
Preparation of the following new SF5-perfluoroalkyl benzene derivatives, m-SF5CF2CF2C6H4X (X=NO2, NH2, OH, I, NHCOCH3, SO2Cl, SO3H, SO3K) has been achieved. The new compounds were characterized by their respective IR, NMR and HRMS or elemental analysis.  相似文献   

12.
金属富勒烯具有表面积大(2 nm2)、整体电中性、金属离子的解离常数Kd为0等独特的性质, 在医学上具有重要的应用价值[1~7]. 要将其用于生物体系, 需引入亲水基团. 水溶性Gd@C82(OH)x已被证实是一种比临床上应用的GdDTPA更好的核磁成像造影剂(其弛豫率比GdDTPA高20倍[7]), 并有望用作放射性示踪剂和放射性药物等, 且在生物体内外具有稳定性[2~6], 是生物医学上很有吸引力的材料. 本文在高效合成、分离纯化 Gd@C82的基础上合成了其多羟基衍生物、多取代氨基酸衍生物和多取代氨基磺酸衍生物, 并作了初步分析.  相似文献   

13.
合成了大黄素类蒽醌衍生物1,4-二甲基-6,8-二甲氧基-9,10-蒽醌(1)并应用紫外光谱、荧光光谱、圆二色谱等方法研究了其与牛血清白蛋白(BSA)和小牛胸腺DNA(ct-DNA)的相互作用.荧光光谱结果表明,化合物1与BSA的相互作用主要以静态猝灭方式使BSA的内源性荧光发生猝灭;圆二色谱表明,化合物1通过疏水作用及形成氢键破坏了α-螺旋结构,导致BSA分子中的α-螺旋含量下降.在pH 7.4时固定DNA的浓度,加入化合物1后,紫外光谱的最大吸收峰发生红移且吸光度加大.荧光光谱表明,化合物1与DNA-4S green NC的结合为竞争性抑制,并可使溶液体系荧光猝灭;圆二色谱表明,随着化合物1的加入,DNA碱基间作用能迅速减弱,表明化合物1与DNA之间为嵌插作用.此外,MTT方法的结果表明,化合物1对结肠癌细胞株HCT116增殖有明显的抑制作用.  相似文献   

14.
Three water-soluble metallofullerene derivatives have been synthesized.IRand XPSanalysis indicate that they have average compositions of Gd@C82(OH)22, Gd@C82(OH)6(NHCH2CH2SO3H)8and Gd@C82(OH)5(NHCH2COOH)9, respectively.They are particularly interesting in medical application.  相似文献   

15.
Vertical ionization energies (IE) of aryl and carbonyl derivatives of diazomethane have been determined by photoelectron spectroscopy. The types of the highest occupied molecular orbitals (HOMO) in these molecules are identified.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 2, pp. 325–328, February, 1993.  相似文献   

16.
Interaction of R n M-derivatives of 4-nitrophenol and thiophenol (R n M= PhHG, PPh3Au, Ph3Sn, Ph4Sb) with a set of inorganic and organic anions (Cl, Br, I, CN, [PhOCO], [4-NO2C6H4OCO]) was studied by IR and electronic spectroscopy in solvents with different polarities and coordinating properties (C6H6, CH2Cl2, DMSO). The dependence of the character of the interaction with the anions on the nature of the metal atom and heteroatom, the type of anions and the nature of the media was analyzed. Such interaction leads to ion-molecular complexes, and also to dissociation of the X-M bond (X = O, S, M = Au, Hg. Sb) with formation of the (4-NO2C6H4X) anion even in weakly polar media. Only in the case of 4-NO2C6H4OSnPh3 does the reaction stop at the stage of complex formation. In other cases the role of complex formation with anions is less than with neutral coordinating reagents.Translated fromIzvestiya Akademii Nauk, Seriya Khimicheskaya, No. 7, pp. 1838–1841, July, 1996.  相似文献   

17.
18.
Stone-Wales旋转是富勒烯异构化的基本方式,了解其特征和规律对于理解富勒烯和富勒烯衍生物的形成至关重要.本文采用密度泛函理论方法系统研究了富勒烯和富勒烯衍生物的Stone-Wales旋转.结果显示,富勒烯异构体趋向于从高B55键(两个五元环共用的边)结构向低B55结构转化,满足独立五元环原则的结构或具有低B55键数的异构体在热力学上更为有利.相反,对于富勒烯衍生物,具有更多B55的异构体不仅在热力学上更有利,而且从动力学角度讲,从满足独立五元环原则的结构向不满足的结构的转变比相反过程更容易.这些结果可以解释目前的相关实验事实,暗示了富勒烯衍生物可能是先衍生化后异构化而形成.  相似文献   

19.
The interaction of acetamidine and phenylamidine with peri-R-ethynyl-9,10-anthraquinones in refluxing n-butanol leads to the formation of cascade transformations products: addition/elimination/cyclization―2-R-7H-dibenzo[de,h]quinolin-7-ones and(or) 2-R-3-aroyl-7H-dibenzo[de,h]quinolin-7-ones. The anti-inflammatory and antitumor properties of the new 2-R-7H-dibenzo[de,h]quinolin-7-ones were investigated in vivo, in vitro, and in silico. The synthesized compounds exhibit high anti-inflammatory activity at dose 20 mg/kg (intraperitoneal injection) in the models of exudative (histamine-induced) and immunogenic (concanavalin A-induced) inflammation. Molecular docking data demonstrate that quinolinones can potentially intercalate into DNA similarly to the antitumor drug doxorubicin.  相似文献   

20.
Aroylpyruvic acids and their methyl esters react witho-aminophenyldiphenylmethanol to form 4-aryl-2-[2-(1-hydroxydiphenylmethyl)phenylamino]-4-oxobut-2-enoic acids and their esters. The α-enamino acids obtained undergo intramolecular heterocyclization in the presence of Ac2O to affort substituted 4,5-dihydrobenzo[e][1,4]oxazepin-3(1H)-ones. The reaction of 5-arylfuran-2,3-diones witho-aminophenyldiphenylmethanol leads to products of decyclization, 2-(1-hydroxydiphenylmethyl)phenylamides of 4-aryl-2-hydroxy-4-oxobut-2-enoic acid, which upon heating in AcOH or Ac2O yield 3-aroylacetyl-1,1-diphenyl-1H-benzo[d][1,3]oxazines. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 11, pp. 2317–2319, November, 1998.  相似文献   

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