α-(2-噻唑基脲基)膦酸二苯酯的合成

报道了一种简便的合成取代脲基膦酸酯的通用的新方法。在二氯甲烷中,三乙胺为缚酸剂的条件下,α-氨基膦酸二苯酯与三聚光气反应形成α-异氰酸基膦酸酯2,2不经分离,直接与2-氨基(苯并)噻唑加成得到α-(2-噻唑基脲基)膦酸二苯酯3,产率55.0%-88.9%。     

Molecular Modeling on the Complexation of Cyclobis(paraquat-p-phenylene) with Tetrathiafulvalenes

PM3, HF/3-21g*, and B3LYP/6-31g* calculations on the inclusion complexation of cyclobis(paraquat-p-phenylene) with tetrathiafulvalenes show that ab initio methods are much more reliable in the modeling. The results, in agreement with the experimental observations, indicate that instead of the extended -surface, the better electron-donor property of the pyrrolo-annelated tetrathiafulvalene makes it a better substrate than tetrathiafulvalene.     

Hypercoordinated compounds of gold(I)

Mono- and binuclear gold(I) derivatives ofortho-substituted diphenyl ether, C₆H₅OC₆H₄AuPPh₃ and O(C₆H₄)₂(AuPPh₃)₂, were prepared by the reaction of the 2,2'-dilithium derivative of diphenyl ether with ClAuPPh₃. X-Ray structural study has shown that these compounds contain secondary intramolecular bonds between the gold and oxygen atoms. The interaction of C₆H₅OC₆H₄AuPPh₃ with (AuPPh₃)BF₄ affords the [C₆H₅OC₆H₄(AuPPh₃)₂]BF₄ cationic complex. The latter reacts with PPh₃ to give the starting C₆H₅OC₆H₄AuPPh₃ complex.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 4, pp. 729–736, April, 1994.The authors wish to thank A. L. Blyumenfel'd for recording³¹P NMR spectra, D. V. Zagorevskii and K. V. Kazakov who obtained mass spectra, and Yu.L. Slovokhotov who carried out the EXSAFS study.The study described in the present paper was partly supported by the International Scientific Fund, grant N Ch. 002479.     

PdCl_2-Mn(OAc)_2催化苯酚氧化羰基化合成碳酸二苯酯

碳酸二苯酯 ( DPC)是重要的有机碳酸酯 ,它可用于合成许多有机化合物、医药、农药、高分子材料等 [1] .最近日本 Ashia公司与意大利Enichem公司联合开发了双酚 A与 DPC经熔融聚合法制备聚碳酸酯的非光气法新工艺 [2 ] ,使得聚碳酸酯生产工艺朝“绿色化清洁生产”方向取得突破性进展 ,也使得 DPC的合成成为研究的热点 .合成 DPC的方法有光气法、酯交换法及氧化羰基化法 ,其中 ,氧化羰基化法更是引人注目 [1,3 ] ,它是用苯酚与 CO、O2 反应一步合成 DPC的方法 ,具有工艺简单 ,原料易得等优点 ,且避免了使用剧毒的光气 ,是一条“绿色…     

Molecular mechanics calculations on carbonyl compounds. III. Cycloketones

Molecular mechanics (MM4) calculations were carried out on cycloketones for ring sizes ranging from 4 to 11 carbon atoms. The MM4 relative energies for the various conformations of the cycloketones were compared to density functional theory (DFT) calculations (B3LYP/6‐31G*), which were also carried out in this work. For small ring sizes (n=4–6), calculated molecular geometries, dipole moments, moments of inertia, and vibrational spectra were compared to experimental data. The axial–equatorial energy differences in methyl‐substituted cyclohexanones were also calculated by MM4 and compared to ab initio, DFT, and experimental results. The results of the MM4 studies on cycloketones showed significant improvement from those of MM3 calculations performed in parallel with the MM4 calculations. © 2001 John Wiley & Sons, Inc. J Comput Chem 22: 1451–1475, 2001     

阿托伐他汀钙与β-环糊精相互作用的研究及应用

采用线性扫描伏安法和循环伏安法并结合紫外分光光度法研究了新型抗血脂紊乱药物阿托伐他汀钙(AC)与β-环糊精(-βCD)的相互作用.探讨了-βCD对AC的峰电流及AC对-βCD吸附峰电流的影响,测得在0.06mol/LKH2PO4-Na2HPO4(pH=7.17)缓冲溶液中,AC与-βCD包结比为1:1,用电流法测得包结物的形成常数为9.09×104L/mol.根据碱性介质条件下β-CD分子与AC形成包结物而使β-CD吸附峰电流减小的特性,建立了一种利用β-CD间接测定AC的伏安方法.     

Molecular Recognition of Bridged Bis （β－cyclodextrin） s Linked by Phenylenediseleno Tether on the Primary or Secondary Side with Fluorescent Dyes

A novel β‐cyclodextrin dimer, 2, 2′‐o‐phenylenediseleno‐bridged bis (β‐cyclodextrin) (2), has been synthesized by reaction of mono‐[2‐O‐(p‐tolylsulfonyl)]‐β‐cyclodextrin and poly(o‐phenylenediselenide). The complexation stability constants (K₂) and Gibbs free energy changes (‐ΔG°) of dimer 2 with four fluorescence dyes, that is, ammonium 8‐anilino‐1‐naphthalenesulfonate (ANS), sodium 6‐(p‐toluidino)‐2‐naphthalenesulfonate (TNS), Acridine Red (AR) and Rhodamine B (RhB) have been determined in aqueous phosphate buffer solution (pH = 7.2, 0.1 mol‐L^?1) at 25 °C by means of fluorescence spectroscopy. Using the present results and the previously reported corresponding data of β‐cyclodextrin (1) and 6, 6′‐o‐phenylenediseleno‐bridged bis (β‐cyclodextrin) (3), binding ability and molecular selectivity are compared, indicating that the bis (β‐cyclodextrin)s 2 and 3 possess much higher binding ability toward these dye molecules than parent β‐cyclodextrin 1, but the complex stability constant for 2 linked from the primary side is larger than that of 3 linked from the secondary side, which is attributed to the more effective cooperative binding of two hydrophobic cavities of host 3 and the size/shape‐fit relationship between host and guest. The binding constant (K₂,) upon inclusion complexation of host 3 and AR is enhanced by factor of 27.3 as compared with that of 1. The 2D ¹H NOESY spectrum of host 2 and RhB is performed to confirm the binding mode and explain the relative weak binding ability of 2.     

Selective Pseudo-Rotaxane Type Complex Formation of Zinc(II) (t-butylatedtetraphenyl) porphyrin-Viologen Linked Compounds with tri-O-methyl-β-Cyclodextrin

Inclusion complexation behavior of 2,3,6−tri-O-methyl-β-cyclodextrin (TM-β-CD) with zinc(II) 5,10,15-tri-(4-t-butyl-phenyl)-20-(4-(n-alkyloxy)phenylporphyrin covalently linked with violgen by a polymethylene chain (Zn-t- bu-PC _n V²⁺; n=4, 6, 8, 10 and 12) was investigated by means of ¹H NMR, UV/Vis absorption spectroscopies in acetonitrile-water (1:1, v/v). The ¹H NMR spectra indicated that Zn-t-bu-PC _n V²⁺ presumably existed as a mixture of a dimer and a monomer in high concentration (>1×10⁻³ mol dm⁻³), and the dimer was degraded by the complex formation with TM-β-CD. The ¹H NMR spectra of these compounds as a function of [TM-β-CD] showed the selective formation of 1:1 (=Zn-t-bu-PC _n V²⁺: TM-β-CD) pseudo-rotaxane type complexes. The chemical modification by t-butyl groups on porphyrin showed a good protective effect on inclusion of benzene groups into the TM-β-CD cavity. These rotaxane formation constants (K) were determined by titration studies using UV/Vis absorption spectroscopy. These complex formation constants were somewhat affected by the spacer methylene chain between the porphyrin and viologen. The value of K for Zn-t-bu-PC₄V²⁺·TM-β-CD is 1.0×10³ M⁻¹ which is the smallest whereas those for Zn-t-bu-PC _n V²⁺·TM-β-CD (n=8, 10, 12) were similar (1.0×10⁴ M⁻¹).     

Molecular mechanics calculations on carbonyl compounds. IV. Heats of formation

Molecular mechanics (MM4) calculations on the heats of formation of aldehydes and ketones were carried out for a total of 59 compounds (10 aldehydes and 49 ketones). Optimization of the heat of formation parameters was obtained by a least squares fit to the experimentally known heats of formation. With the optimized MM4 heat of formation parameters, the MM4 calculated heats of formation showed significant improvement over those of MM3. The standard and weighted root mean square deviations for the MM4 values were 0.35 and 0.31 kcal mol^?1, respectively, whereas for the MM3 values they were 0.42 and 0.39 kcal mol^?1, respectively. © 2001 John Wiley & Sons, Inc. J Comput Chem 22: 1476–1483, 2001     

Experimental (NMR) and Theoretical (MD Simulations) Studies on the Conformational Preference of Three Cycloalkanols when Included in β-Cyclodextrin

The inclusion complexes between three cycloalkanols (cyclopentanol, cyclohexanol and cycloheptanol) and β-cyclodextrin (β-CD) have been studied by NMR experiments, and by molecular dynamics (MD) simulations. Complexes present medium to small association constants. All experimental data show the equatorial conformer as the most stable after complexation because no changes were detected in the coupling constants of the H1 protons. Intermolecular ROE experiments suggest that while cyclopentanol is deeply included into the β-CD cavity, cyclohexanol and cycloheptanol occupy mainly the wider entrance. The MD simulations agree with the experimental data (equatorial conformers are always the most stable), and average geometries coincide with those deduced from the ROE experiments.     

Experimental and Molecular Mechanical Studies of Complexation of Some 2H- and 3H- Indole Derivatives with Aqueous β-Cyclodextrin

Phase solubility diagrams (PSDs) at 25 ^∘C and molecular mechanical (MM) modeling were used to study the aqueous complexation of some 2H- and 3H-indole derivatives with β-cyclodextrin (β-CD). Among the 3H-indole derivatives investigated in this work, indole-3H-butyric acid forms the most stable 1:1 complex of the B _s -type PSD, whereas shorter chain derivatives form soluble 1:1 complexes (A _L -type PSDs) with their stability increasing as the chain length increases. Indole-2 carboxylic acid forms highly stable 1:1 and 1:2 complexes, with the lower-order complex reaching saturation first (B _s -type PSD). MM modeling indicates that the stability of the complex is highly correlated with the flexibility of the 3H-indole hydrocarbon chain, which yields a better geometrical fit within the β-CD cavity resulting from different hydrophilic interactions. These interactions are represented in the H-bonding of the carboxyl group with the primary hydroxyl group network that is situated at the narrow rim of the cavity, and also by a favorable interaction of the aromatic ring with the hydroxyl group network at the other rim.     

Factors Contributing to Solubility Synergism of Some Basic Drugs with β-Cyclodextrin in Ternary Molecular Complexes

Ternary complexes exploiting solubility synergism (SSn) between basic drugs and β-cyclodextrin (β-CD) in the presence of an organic hydoxy acid have been reported to provide the pharmaceutical technology with highly soluble ternary complexes, even with the least soluble β-CD. In this work, phase solubility techniques were used to study factors affecting SSn in aqueous solution, which may help in understanding the mechanism involved in ternary complex formation in solution, under equilibrium conditions. The equilibrium solubility of both β-CD and each of 8 structurally unrelated drugs were measured in tandem in the presence of different acid types at low and high pHs, and at different time intervals over a period of 1–40 days. The results indicate that SSn is evident regardless of acid type (organic and inorganic) at low pH, but the extent of SSn is acid type dependant and is limited by the drug salt solubility product constant (pK _sp). Among different drugs, no apparent trend exists between drug salt solubility and the extent of SSn, but lowering drug salt solubility by increasing pH depresses SSn. The results also reveal no apparent trend between the magnitude of the complex formation constant (K _ij) and SSn. For example, drugs of low K _ij values such as astemizole, cisapride and sildenafil do not show any SSn, yet ketotifen and pizotifen, which also have low K _ij values, exhibit substantial SSn. However, the solublizing power of β-CD represented by the slope of phase solubility diagram can be used as a marker for SSn (slopes exceeding 0.4 induce SSn).     

Molecular Modifications and Control of Processes to Facilitate the Synergistic Degradation of Polybrominated Diphenyl Ethers in Soil by Plants and Microorganisms Based on Queuing Scoring Method

In this paper, a combination of modification of the source and regulation of the process was used to control the degradation of PBDEs by plants and microorganisms. First, the key proteins that can degrade PBDEs in plants and microorganisms were searched in the PDB (Protein Data Bank), and a molecular docking method was used to characterize the binding ability of PBDEs to two key proteins. Next, the synergistic binding ability of PBDEs to the two key proteins was evaluated based on the queuing integral method. Based on this, three groups of three-dimensional quantitative structure-activity relationship (3D-QSAR) models of plant-microbial synergistic degradation were constructed. A total of 30 PBDE derivatives were designed using BDE-3 as the template molecule. Among them, the effect on the synergistic degradation of six PBDE derivatives, including BDE-3-4, was significantly improved (increased by more than 20%) and the environment-friendly and functional evaluation parameters were improved. Subsequently, studies on the synergistic degradation of PBDEs and their derivatives by plants and microorganisms, based on the molecular docking method, found that the addition of lipophilic groups by modification is beneficial to enhance the efficiency of synergistic degradation of PBDEs by plants and microorganisms. Further, while docking PBDEs, the number of amino acids was increased and the binding bond length was decreased compared to the template molecules, i.e., PBDE derivatives could be naturally degraded more efficiently. Finally, molecular dynamics simulation by the Taguchi orthogonal experiment and a full factorial experimental design were used to simulate the effects of various regulatory schemes on the synergistic degradation of PBDEs by plants and microorganisms. It was found that optimal regulation occurred when the appropriate amount of carbon dioxide was supplied to the plant and microbial systems. This paper aims to provide theoretical support for enhancing the synergistic degradation of PBDEs by plants and microorganisms in e-waste dismantling sites and their surrounding polluted areas, as well as, realize the research and development of green alternatives to PBDE flame retardants.     

多面体碳烷的分子轨道方法研究

利用INDO自洽场方法和Edmiston-Ruedenberg定域化方法,计算了多面体碳烷C_2nH_2n(n=2,3,4,5和10)及其骨架C_2n,讨论了它们的电子结构、稳定性和化学键性质。     

Antimicrobial activity of organotin(IV) compounds: a review

A comprehensive review on antimicrobial activity of organotin(IV) compounds is presented. Copyright © 2008 John Wiley & Sons, Ltd.     

Synthesis of A novel Bridged Bis(β-cyclodextrin)s Possessing Phenanthroline Tether and Its Molecular Binding Ability with Dyes

A novel β-cyclodextrin dimer bearing 2,9-diformyl-1,10-phenanthroline tether 4 has been synthesized and its inclusion complexation behavior with two triangular model substrates (RhB and BG) has been investigated through fluorescence and ultraviolet spectrometry.The result obtained indicated that novel bridged bis(β-cyclodextrin)s could significantly cnhance the original molccular binding ability of native β-cyclodextrin by cooperative binding of two hydrophobic cavities.     

Formation of a PIII−C(sp2) bond by addition of diphenyl(trimethylsilyl)phosphine to activated acetylenes

Diphenyl(trimethylsilyl)phosphine reacts with alkoxy(alkyl)acetylenes to give mixtures of addition products, (2-alkoxy-2-trimethylsilylalkenyl)diphenylphosphines and (2-alkoxyalkenyl)diphenylphosphines. The reaction is sensitive to the solvent; in MeCN, it gives only nonsilylated products. (1-Alkoxyethenyl)diphenylphosphines were obtained as the main products upon the reaction of Ph₂PSiMe₃ with terminal alkoxyalkynes, irrespective of the reaction conditions. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 9, pp. 1792–1796, September, 1998.     

含苯并噻唑杂环的α-氨基膦酸二苯酯的合成及生物活性

α氨基膦酸作为氨基酸的含磷类似物,具有广泛的除草［１］、杀菌［２］和植物生长调节活性［３］．最近的研究表明,某些α氨基膦酸衍生物还具有较好的抗植物病毒活性［４,５］．在研究植物病毒抑制剂的过程中,我们发现含苯并噻唑杂环的α氨基膦酸二乙酯类化合物...     

Study on Triplex DNA by Use of Molecular “Light Switch“ Complex of Ru(phen)2(dppx)^2

A new method for the study of triplex DNA is established according the fluorescence enhancement of molecular “Light Switch“ complex of Ru(phen)2(dppx)^2 when it intercalate into triplex DNA.Because the fluorescence intensity of Ru(phen)2(dppx)^2 bonded to triplex DNA is in ths case higher than that bonded to duplex DNA in certain range of DNA concentration,the method is much more sensitive than other methods reported previously.