含1,3,4-噁二唑和1,3,4-噻二唑的硫醚类化合物的合成

在KOH作用下,芳甲酰肼1a～1e与CS2环化生成5-芳基-2-巯基-1,3,4-噁二唑(2a～2e);将2a～2e与氯乙酸乙酯反应,生成2-(5-芳基-1,3,4-噁二唑)硫基乙酸乙酯(3a～3e);3a～3e肼解得2-(5-苯基-1,3,4-噁二唑-2-硫基)乙酰肼(4a～4e);4a～4e与芳酰基异硫氰酸酯5a～5d反应得到双酰基氨基硫脲衍生物A1～A19;A1～A19在H2SO4催化下环合得到目标化合物B1～B19;目标化合物的结构经IR,1H NMR,MS,HRMS确证.     

噁二唑肟醚取代的均三唑水杨醛席夫碱衍生物的合成及抗菌活性

4-氨基-3-苯基-5-巯基-均.三唑(1)在无水乙酸钠作用下与β-氯苯丙酮(2)缩合得氨基三唑硫基苯丙酮(3).化合物3与盐酸羟胺肟化得羰基肟化物(4),采用氯甲基(噁)二唑(5)对化合物4的肟羟基醚化得均三唑席夫碱(噁)二唑肟醚(6a～6e).肟化物6a～6e与水杨醛缩合得到目标物席夫碱7a～7e.初步的体外抗菌实验表明,席夫碱肟醚类化合物7a～7e的活性明显高于氨基肟醚类化合物6a～6e,且对革兰氏阳性(Sa)的活性高于对革兰氏阴性菌(Ec)的.     

微波辐射下合成5-(2-甲基/三氟甲基-苯并咪唑-1-亚甲基)-3-(苯基/p-取代苯基)-2H-1'''',2'''',4''''-三唑[3,4-b]-1",3",4"-噻二嗪

分别采用微波辐射法和加热回流的常规方法,将1-氨基-2-(2-甲基/三氟甲基-苯并咪唑-1-亚甲基)-5-巯基-1,3,4-三唑与α-溴代芳基乙酮3a～3e反应,合成了一系列未见文献报道的1,2,4-三唑[3,4-b]-1',3',4'-噻二嗪类化合物4a～4e和5a～5e.微波辐射法具有反应时间短、产率高、副反应少等优点.标题化合物经元素分析,IR,1HNMR,MS确证结构.     

新型醚键连接的杂环功能基杯[4]芳烃衍生物的合成及结构

以碘化钠为催化剂,在氢氧化钠存在下2-氯乙氧基乙醇分别与2-巯基芳香杂环化合物反应制得相应的芳香杂环衍生物1a～1e.以三乙胺为缚酸剂,其与对甲苯磺酰氯反应,生成了活化羟基的衍生物2a～2e.在碳酸钾存在下,对叔丁基杯[4]芳烃分别与2a～2e反应生成醚键连接的杂环功能基杯[4]芳烃衍生物3a～3e,并通过1HNMR,13CNMR,IR,MS和元素分析的确证.同时,X射线分析确定了杯[4]芳烃3a,3b和3d的晶体结构.     

3-芳基-5-巯基-1,2,4-三唑的亲核取代反应研究

以3-芳基-5-巯基-1,2,4-三唑为原料合成了20个3-芳基-1,2,4-三唑-5-巯基乙酸乙酯(2a～e)、3-芳基-1,2,4-三唑-5-巯基乙酸(3a～e)、3-芳基-5,6-二氢噻唑并[2,3-c]均三唑(5a～e)和3-芳基-6,7-二氢均三唑并[3,4-b][1,3]噻嗪(6a～e)。研究了3a～e在微波辐射下的环化反应，合成了5个3-芳基-5-氧代-6H-噻唑[2,3-c]均三唑(4a～e)。产物经元素分析、红外、核磁共振以及质谱方法确定了结构。初步研究了代表化合物的生物活性。     

2-巯基苯并咪唑及其类似物互变异构的理论研究

采用B3LYP/6-311G**方法, 计算了2-巯基苯并咪唑及其类似物(2-巯基苯并噁唑、2-巯基苯并噻唑、2-羟基苯并咪唑、2-羟基苯并噁唑、2-羟基苯并噻唑以及2-巯基咪唑、2-巯基噁唑、2-巯基噻唑、2-羟基咪唑、2-羟基噁唑、2-羟基噻唑)的(硫)醇式与(硫)酮式结构进行质子迁移的3种可能途径: (a)分子内质子迁移; (b)水助质子迁移; (c)甲醇助质子迁移．结果表明, 途经b和c所需要的活化能较小, 氢键在降低反应活化能方面起重要作用．采用PCM方法研究了反应体系的溶剂化效应．结果表明孤立分子、一水合物和一甲醇合物的最稳定异构体相同, 都为(硫)酮式, 与气相结论一致．溶剂化效应对异构化能垒的影响较小.     

2-(4-β-D-吡喃阿洛糖苷-苯基)-4-芳基-2,3-二氢-1,5-苯并硫氮杂的合成及镇静活性的研究

以豆腐果苷为原料,与4-取代苯乙酮发生Claisen-Schimidt反应,得到一系列E-4-β-D-吡喃阿洛糖苷-苯乙烯基-4-取代苯酮衍生物1a～1e,再将1a～1e与邻氨基苯硫酚发生1,4-Michael反应,得到2-(4-β-D-吡喃阿洛糖苷-苯基)-4-芳基-2,3-二氢-1,5-苯并硫氮杂衍生物2a～2e,以上化合物均未见文献报道,其结构经1H NMR,IR,MS加以确证,并对2a～2e进行了药理活性筛选.结果表明,部分化合物具有良好的镇静活性.其中,化合物2a(200mg·kg-1),2b(200mg·kg-1),2c(200mg·kg-1),2d(200mg·kg-1),2e(200mg·kg-1)与豆腐果苷相比较具有更强的活性.     

2-(4-β-D-吡喃阿洛糖苷-苯基)-4-芳基-2,3-二氢-1,5-苯并硫氮杂革的合成及镇静活性的研究

以豆腐果苷为原料,与4-取代苯乙酮发生Claisen-Schimidt反应,得到一系列E-4-β-D-吡喃阿洛糖苷-苯乙烯基-4-取代苯酮衍生物1a～1e,再将1a～1e与邻氨基苯硫酚发生1,4-Michael反应,得到2-(4-β-D-吡喃阿洛糖苷-苯基)-4-芳基-2,3-二氢-1,5-苯并硫氮杂革衍生物2a～2e,以上化合物均未见文献报道,其结构经1H NMR,IR,MS加以确证,并对2a～2e进行了药理活性筛选.结果表明,部分化合物具有良好的镇静活性.其中,化合物2a(200 mg·kg-1),2b(200 mg·kg-1),2c(200 mg·kg-1),2d(200 mg·kg-1),2e(200 mg·kg-1)与豆腐果苷相比较具有更强的活性.     

丝光沸石催化愈创木酚选择性烷基化反应的研究

本文研究了氢型丝光沸石催化愈创木酚(1)与莰烯(2)的选择性烷基化反应. 该烷基化反应产物萜基愈创木酚(3～6)中含5-异莰基愈创木酚(3a)25.0%, 经氢化, 氢解得萜基环己醇混合物, 含人造檀香主要成份反式-3-异莰基环己醇(7a)23.0%. 通过IR, ^1H NMR 和MS鉴定了烷基化产物色谱图中的5个主要化合物.     

2-(4-β-D-吡喃阿洛糖苷-苯基)-4-芳基-2,3-二氢-1,5-苯并硫氮杂的合成及镇静活性的研究

以豆腐果苷为原料,与4-取代苯乙酮发生Claisen-Schimidt反应,得到一系列E-4-β-D-吡喃阿洛糖苷-苯乙烯基-4-取代苯酮衍生物1a～1e,再将1a～1e与邻氨基苯硫酚发生1,4-Michael反应,得到2-(4-β-D-吡喃阿洛糖苷-苯基)-4-芳基-2,3-二氢-1,5-苯并硫氮杂革衍生物2a～2e,以上化合物均未见文献报道,其结构经1H NMR,IR,MS加以确证,并对2a～2e进行了药理活性筛选.结果表明,部分化合物具有良好的镇静活性.其中,化合物2a(200 mg·kg-1),2b(200 mg·kg-1),2c(200 mg·kg-1),2d(200 mg·kg-1),2e(200 mg·kg-1)与豆腐果苷相比较具有更强的活性.     

Silver(I) complexation of linked 2,2'-dipyridylamine derivatives. Synthetic, solvent extraction, membrane transport and X-ray structural studies

Synthesis of the 2,2'-dipyridylamine derivatives di-2-pyridylaminomethylbenzene 1, 1,2-bis(di-2-pyridylaminomethyl)benzene 2, 1,3-bis(di-2-pyridylaminomethyl)benzene 3, 2,6-bis(di-2-pyridylaminomethyl)pyridine 4, 1,4-bis(di-2-pyridylaminomethyl)benzene 5, and 1,3,5-tris(di-2-pyridylaminomethyl)benzene 6 are reported together with the single-crystal X-ray structures of 2, 3, and 5. Reaction of individual salts of the type AgX (where X = NO(3)(-), PF(6)(-), ClO(4)(-), or BF(4)(-)) with the above ligands has led to the isolation of thirteen Ag(I) complexes, nine of which have also been characterised by X-ray diffraction. In part, the inherent flexibility of the respective ligands has resulted in the adoption of a range of coordination arrangements. A series of liquid-liquid (H(2)O/CHCl(3)) extraction experiments of Ag(I) with varying concentrations of 1-6 in the organic phase have been undertaken, with the counter ion in the aqueous phase being respectively picrate, perchlorate and nitrate. In general, extraction efficiencies for a given ionophore followed the Hofmeister order of picrate > perchlorate > nitrate; in each case the tris-dpa derivative 6 acting as the most efficient extractant of the six systems investigated. Competitive seven-metal bulk membrane transport experiments (H(2)O/CHCl(3)/H(2)O) employing the above ligands as the ionophore in the organic phase and equimolar concentrations of Co(II), Ni(II), Zn(II), Cu(II), Cd(II), Pb(II) and Ag(I) in the aqueous source phase were also undertaken, with transport occurring against a pH gradient. Under the conditions employed 1 and 5 yielded negligible transport of any of the metals present in the source phase while sole transport selectivity for Ag(I) was observed for 2-4 and 6.     

Synthesis and complexing properties of [2.n](2,6)pyridinocrownophanes

[2.n](2,6)Pyridinocrownophanes (3a-e) were efficiently prepared by intramolecular [2 + 2] photocycloaddition of vinylpyridine derivatives under irradiation using a 400-W high-pressure mercury lamp through a Pyrex filter. They were of cis-configuration with respect to the cyclobutane ring, which was proven by the specific methine proton NMR resonances at delta 3.98-4.08. From ESI-MS analysis 3a-e were found to form 1:1 complexes with Ag+ cation. In a liquid-liquid extraction, 3 showed the highest affinity toward Ag+ cation among several heavy metal nitrates. In this series, 3c possessing four ethereal oxygen atoms was found to show the highest Ag+ affinity, according to the liquid-liquid extraction and determination of stability constant with the cation. The photoreactivity of precursor vinylpyridines is discussed by the predictor gamma(r(c)) proposed by Caldwell.     

New Tripodal Ligands Containing Aza-Thioethers as Selective Extractants for Silver(I)

A new series of tripodal receptors bearing imine and thioether units, have been synthesized in high yields by simple condensation method. The binding properties of these ligands towards alkali, alkaline earth and transition metal ions have been established by extraction and transport experiments. These podands have highest extraction and transport rate for Ag(I). The complexation of Ag(I) with the receptors has been established using ¹H-and ¹³C-NMR spectroscopy.This revised version was published online in July 2005 with a corrected issue number.     

Coordination chemistry of the solvated AgI and AuI ions in liquid and aqueous ammonia, trialkyl and triphenyl phosphite, and tri-n-butylphosphine solutions

The coordination chemistry of solvated Ag(I) and Au(I) ions has been studied in some of the most strong electron-pair donor solvents, liquid and aqueous ammonia, and the P donor solvents triethyl, tri-n-butyl, and triphenyl phosphite and tri-n-butylphosphine. The solvated Ag(I) ions have been characterized in solution by means of extended X-ray absorption fine structure (EXAFS), Raman, and (107)Ag NMR spectroscopy and the solid solvates by means of thermogravimetry and EXAFS and Raman spectroscopy. The Ag(I) ion is two- and three-coordinated in aqueous and liquid ammonia solutions with mean Ag-N bond distances of 2.15(1) and 2.26(1) A, respectively. The crystal structure of [Ag(NH3)3]ClO4.0.47 NH3 (1) reveals a regular trigonal-coplanar coordination around the Ag(I) ion with Ag-N bond distances of 2.263(6) A and a Ag...Ag distance of 3.278(2) A separating the complexes. The decomposition products of 1 have been analyzed, and one of them, [Ag(NH3)2]ClO4, has been structurally characterized by means of EXAFS, showing [Ag(NH3)2] units connected into chains by double O bridges from perchlorate ions; the Ag...Ag distance is 3.01(1) A. The linear bisamminegold(I) complex, [Au(NH3)2]+, is predominant in both liquid and aqueous ammonia solutions, as well as in solid [Au(NH3)2]BF4, with Au-N bond distances of 2.022(5), 2.025(5), and 2.026(7) A, respectively. The solvated Ag(I) ions are three-coordinated, most probably in triangular fashion, in the P donor solvents with mean Ag-P bond distances of 2.48-2.53 A. The Au(I) ions are three-coordinated in triethyl phosphite and tri-n-butylphosphine solutions with mean Au-P bond distances of 2.37(1) and 2.40(1) A, respectively.     

Selective transport of Ag(Ⅰ) ion across a bulk liquid and polymer membranes incorporated with di-N-benzylated O_3N_2 donor macrocycles

<正>The selective bulk liquid membrane and polymer membrane transports of Ag(Ⅰ) from an aqueous solution containing seven metal cations,Co(Ⅱ),Ni(Ⅱ),Cu(Ⅱ),Zn(Ⅱ),Ag(Ⅰ),Cd(Ⅱ) and Pb(Ⅱ),was studied.The source phases contained equimolar concentrations of the above-mentioned cations,with the source and receiving phases being buffered at pH 5.0 and 3.0,respectively. Ag(Ⅰ) ion transport occurred with a good efficiency from the aqueous source phases across the bulk liquid membrane and polymer membrane(derived from cellulose triacetate) containing ligand 1 as the ionophores,into the aqueous receiving phases.Clear transport selectivity for Ag(Ⅰ) was observed using ligand 1.There was no selectivity for the cations using ligand 2 in the both bulk liquid membrane and polymer membrane transports.     

Synthesis of [1]Benzopyrano[3,4-c][2]benzazepine-6, 8, 13(7H)-triones

Hitherto unknown [1] benzopyrano [3,4-c] [2] benzazepine-6,8,13(7H)-triones (4a-e) have been synthesized by the intramolecular cyclodehydration of N-(2-oxo-2H-1-benzopyran-3-yl) phthalamic acids (3a-e) obtained by the reaction of 3-amino coumarins (1a-e) with phthalic anhydride (2)     

Aminolysis of Y-substituted phenyl X-substituted cinnamates and benzoates: effect of modification of the nonleaving group from benzoyl to cinnamoyl

A kinetic study is reported for reactions of Y-substituted phenyl X-substituted cinnamates (1a-e and 3a-g) and benzoates (2a-e and 4a-g) with a series of alicyclic secondary amines in 80 mol % H2O/20 mol % DMSO at 25.0 +/- 0.1 degrees C. Reactions of 2,4-dinitrophenyl X-substituted cinnamates (1a-e) and benzoates (2a-e) with amines result in linear Yukawa-Tsuno plots. The rho(X) values are much smaller for the reactions of 1a-e than for those of 2a-e. A distance effect and the nature of the reaction mechanism (i.e., a concerted mechanism for 1a-e) have been suggested to be responsible for the small rho(X) values. The Br?nsted-type plots for the reactions of 2,4-dinitrophenyl X-substituted cinnamates (1a, 1c, and 1e) with amines are curved with a decreasing betanuc value from 0.65 to 0.3-0.4. The reactions of Y-substituted phenyl cinnamates (3a-g) with morpholine also result in a curved Br?nsted plot, while the corresponding reactions of Y-substituted phenyl benzoates (4a-e) exhibit a linear Br?nsted plot. It has been concluded that the curved Br?nsted plots found for the reactions of the cinnamates (1a, 1c, 1e, and 3a-g) are not due to a change in the rate-determining step (RDS) but due to a normal Hammond effect for a concerted mechanism, that is, an earlier transition state (TS) for a more reactive amine or substrate.     

Au(I)...Ag(I) metallophilic interactions between anionic units: theoretical studies on a AuAg4 square pyramidal arrangement

We have studied theoretically the organometallic compound (NBu4)2[Au(3,5-C6F3Cl2)2Ag4(CF3CO2)5], whose dianionic part displays a AuAg4 square pyramidal arrangement based on closed-shell Au(I)...Ag(I) interactions between two monoanionic fragments. DFT/B3LYP, ab initio Hartree-Fock (HF), and second-order M?ller Plesset perturbation theory (MP2) calculations have been carried out for simplified model systems. Model system [AuPh2]-...[Ag4(CO2H)5]- (C1) has been chosen from DFT results as an appropriate model for the study of the interactions. The four Au(I)...Ag(I) interactions and two additional C...Ag(I) interactions are observed when dispersion-type interactions are considered in the level of theory (MP2) displaying a metallophilic attraction between two anionic units. The study of model C2 (similar to C1 but with minimized C...Ag(I) interactions) permits the study of the Au(I)...Ag(I) interactions separately, which confirms the existence of stabilizing Au(I)...Ag(I) interactions around 13 kJ.mol(-1) each.     

Rational ligand design for metal ion recognition. Synthesis of a N-benzylated N2S3-donor macrocycle for enhanced silver(I) discrimination

Four previously documented ligand design strategies for achieving Ag(I) discrimination have been applied to the design of a new N-benzylated N2S3-donor macrocycle; the latter shows high selectivity for Ag(I) over Co(II), Ni(II), Cu(II), Zn(II), Cd(II) and Pb(II) in log K and bulk membrane transport studies.     

Coupled transport of Ag(I) ions through triethanolamine–cyclohexanone-based supported liquid membranes

Facilitated transport of silver(I) ions in acidic medium, across a supported liquid membrane (SLM) by using triethanolamine (TEA) as carrier, dissolved in cyclohexanone, has been investigated. The parameters studied are HNO₃ concentration variation in the feed, pH of the feed solution, carrier concentration in the membrane phase, silver(I) ions concentration in the feed phase and KCN concentration in the stripping phase. Increase in H⁺ concentration by increasing HNO₃ concentration from 0.5 to 1 M results into an increase in silver ions flux but a decrease in flux has been found beyond 1 M HNO₃ concentration in the feed, providing a maximum flux of 3.21 × 10⁻⁷ mol/m² s at 1 M HNO₃. Increase in TEA concentration inside the membrane enhances flux with its maximum value at 2.25 M TEA. Further increase in the concentration of TEA leads to a decreased rate of transport due to the increase in viscosity of membrane liquid. The optimum conditions for Ag(I) ions transport are 1 M HNO₃ (feed), 2.25 M TEA (membrane) and 1.5 M KCN in the stripping phase. It has been observed that Ag(I) flux across the membrane tends to increase with increase in Ag(I) ions concentration in the feed phase. Applying the studied conditions to silver plating waste solutions, Ag ions have been removed up to 99% in a time interval of 5 h.