Syntheses,Structures, and Properties of Three Coordiantion Polymers： [Cd2（bpp）1.5（Hbpp）（phen）2]n, [Mn3（Htptc）2（phen）2（H2O）2]n,and {[Cu（btc）0.5（1,4-bib）]？2H2O}nSyntheses,Structures, and Properties of Three Coordiantion Polymers： [Cd2（bpp）1.5（Hbpp）（phen）2]n, [Mn3（Htptc）2（phen）2（H2O）2]n,and {[Cu（btc）0.5（1,4-bib）]？2H2O}n

Hydrothermal reactions of three aromatic polycarboxylic acids and the transitional metal cations in the presence of phen and 1,4-bib afford three new coordination polymers： [Cd2（bpp）1.5（Hbpp）（phen）2]n （1）, [Mn3（Htptc）2（phen）2（H2O）2]n （2）, and {[Cu（btc）0.5（1,4- bib）]·2H2O}n（3） （H2bpp = 2,6-bis（4＇-carboxyphenyl）-4-phenylpyridine, H4tptc = terphenyl-2,5,2＇,5＇-tetracar- boxylic acid, H4btc =biphenyl-2,2＇,4,4＇-tetracarboxylic acid, phen =1,10-phenanthroline, and 1,4-bib = 1,4-bis（1H-imidazol-1-yl）benzene）. Their structures have been determined by single- crystal X-ray diffraction analyses, elemental analyses, IR spectra, and powder X-ray diffraction （PXRD） analyses. In compound 1, the CdII cations are linked by bpp2- to form one ladder structure, based on which a 3D network is constructed with the help of non-covalent interactions. The topology of 2 is a 3D （3,4,5）-connected framework with the Point Schl？fli symbol of （42.6）2（43.62.8）（45.64.8）2. Compound 3 shows an unprecedented 3D （4,4）-connected framework with the Point Schl？fli symbol of （64.82）2（65.8）. Moreover, the luminescent property of 1 has been investigated.     

Two New Organic Supramolecular Complexes Based on 2,3,6,7-Tetrahydroxyl-9,10-dimethyl-9,10-dihydro-9,10-ethanoanthracene and 4,4′-Bipyridine or 4,4′-Bipyridinylethane

Two new organic supramolecular cocrystal complexes C18H18O4·C10H8N2(I) and C18H18O4·C12H10N2(II)(C18H18O4 = 2,3,6,7-tetrahydroxyl-9,10-dimethyl-9,10-dihydro-9,10-ethanoanthracene(LH4), C10H8N2 = 4,4'-bipyridine(bpy) and C12H10N2 = 4,4'-bipyridinylethane(bpe)) have been obtained by mixing LH4 with corresponding bpy or bpe ligand. The two complexes have been determined by X-ray crystal structure analysis, elemental analysis and IR analysis. Compound I crystallizes in the orthorhombic Pnma with a = 9.7078(4), b = 22.4974(10), c = 20.6272(9) V = 4505.0(3)3, Mr = 454.51, Dc. = 1.340 g·cm-3, μ = 0.09 mm-1, F(000) = 1920, Z = 8, R = 0.0503 and wR = 0.1360. Compound II crystallizes in monoclinic C2/c with a = 29.944(6), b = 9.820(2), c = 22.643(5) , V = 5048.4(18)3, Mr = 480.54, Dc. = 1.265 g cm–3, μ = 0.084 mm–1, F(000) = 2032, Z = 8, R = 0.0548 and wR = 0.1600. X-ray single-crystal structure analysis shows that two-dimensional(2D) layer supramolecular structures are formed through hydrogen bonds and π-π interactions in the two complexes. IR analysis also indicates that there are only associated hydroxyl groups in the two complexes.     

Lithium-lithium tetrachloroaluminate reference electrode in thionyl chloride

Three in situ techniques for charging current compensation (c.c.c.) in d.c. polarography are described. These methods envisage the superposition of an a.c. ripple and analogue processing of the response to yield a quantity proportional to the d.c. charging current. The theory of these procedures outlined in this paper, enables one to approach c.c.c. without any reliance on trial and error. Details of the appropriate circuitry and supporting experimental verification of the theory are also presented.     

Zur nomenklatur der phane—II

The new term “Phanes” has been clearly defined and a nomenclature system tentatively developed. This system is comprehensible and of general application and at the same time relatively simple. The notations “nucleus”, “bridge”, “number of bridge members” and “number of ring members” are defined. In order to get a definite characterisation of the phanes which contain a carbocyclic nucleus, a carbocyclic and heterocyclic bridge the following terms: “carbophanes”, “carba-phanes” and “hetera-phanes” have been newly introduced. The prefix “hetera-” has been proposed as a general expression and as a representative term for the syllables “aza-”, “oxa-”, “thia-” and so on. The so called “a-nomenclature” is clearly called “hetera-nomenclature”. The new expressions “heteralogous” and “substitulogous” are explained. As the various examples will show, the “Phane-Nomenclature” can also be applied to the naming of complicated metallocenophanes.     

USE OF A pH-STAT DILUTION TO DETERMINE CRITICAL MICELLE CONCENTRATIONS AND COUNTERION CONCENTRATIONS OF IONIC MICELLES1

The use of a pH-stat to determine the critical micelle concentration (c.m.c.) of ionic micellar solutions is described. Counterion is released with the dilution of an ionic micellar solution at all concentrations above the c.m.c. The titration of the released counterion permits the evaluation of the c.m.c. and the associated amount of counterion for any concentration above the c.m.c. The diluent is the same medium in which the micelle is dissolved. Thus any ionic strength, ion composition, or pH may be used. Examples of the method to determine the c.m.c. of promethazine hydrochloride in water and of tetracaine hydrochloride in 0.128 N NaCl as a function of pH are given. Also the c.m.c of promethazine hydrochloride - Tween 80 mixtures was examined as a function of mole fraction.     

Synthesis,Crystal Structure,and Topology Analysis of One Novel Interpenetrated 2D Cobalt Coordination Polymer, {[Co(HTCB)(4,4'-btb)]·H_2O}_n

One novel cobalt coordination polymer, {[Co(HTCB)(4,4'-btb)]·H2O}n(1, H3TCB= 1,3,5-tris(4-carboxyphenyl)benzene, 4,4'-btb = 4,4'-bis(1,2,4-triazol-3-yl)biphenyl), has been synthesized and characterized by elemental analysis, IR, powder X-ray diffraction(PXRD), and thermogravimetric(TG) analyses. X-ray diffraction analysis reveals that complex 1 is a 2D 2-fold interpenetrated {44,62}-sql [Co(HTCB)(4,4'-btb)] sheet based on the 1D [Co(HTCB)]n chains and1 D [Co(4,4'-btb)]n chains. The crystal of 1 crystallizes in triclinic, space group P 1 with a =9.529(12), b = 13.914(16), c = 14.906(17), V = 1903(4) 3, Z = 2, C45H34N6CoO7, Mr = 829.71,Dc = 1.448 g/cm3, F(000) = 858 and μ(MoKα) = 0.514 mm-1. The final R = 0.0655 and wR = 0.1136 for 6603 observed reflections with I 2σ(I) and R = 0.1136 and wR = 0.1747 for all data.     

Solvothermal Synthesis of a 3D Luminescent Cadmium-organic Framework with msw Topological Net

A new cadmium-organic framework, [Cd2（TBDC）2（DMF）2（H2O）]n （1）, was synthesized by solvothermal reaction of rigid carboxylate ligand 2,3,5,6-tetramethyl-l,4-ben- zenedicarboxylate （H2TBDC） and cadmium nitrate and characterized by elemental analysis, infrared spectrum, thermal analysis, PXRD, single-crystal X-ray diffraction and photoluminescence in the solid state. Compound 1 crystallizes in orthorhombic, space group Pca21 with a = 21.487（6）, b = 7.790（2）, c = 20.666（6） A, C30H40Cd2N2O11, Mr = 829.44, V= 3459.3（16） A3, Z = 4, Dc = 1.593 g.cm-3,μ = 1.29 mm-1, F（000） = 1672, 2.7〈θ〈27.2°, λ（MoKa） = 0.71073 A, T= 293（2） K, the final R = 0.026, wR = 0.0548 and S = 1.027. X-ray diffraction analysis reveals that complex 1 possesses a 3D framework and exhibits rnsw net. Thus, the solid-state luminescent spectrum of 1 displays that the emission of cadmium（lI） complex shows a peak at 317 nm upon 250 nm excitation at room temperature.     

Pros and cons of σ -aromaticity

A discussion of σ-aromaticity requires a distinction between σ-conjugation, σ-electron delocalization, and σ-bond delocalization, all of which can be considered as prerequisites of σ-aromatic character. All molecules with three or more atoms encounter σ-conjugative interactions. Also, all σ-electrons are delocalized if the term delocalization is taken in its quantum theoretical meaning. However, σ-conjugation and σ-electron delocalization do not necessarily imply σ-bond delocalization. - One can distinguish between three different modes of σ-delocalization: ribbon delocalization in acyclic molecules and larger rings, surface delocalization in small rings, and volume delocalization in cage compounds. Surface delocalization of σ-electrons is found to lead to σ-bond delocalization. An example is cyclopropane. Bonding in cyclopropane can only be described in terms of nonclassical 2-electron 3-center and 4-electron 3-center bonds. Application of the criteria used to define π-aromaticity reveals that the properties of cyclopropane are in line with these criteria and that the term σ-aromaticity cannot be rejected on the grounds that aromaticity is restricted to π-electrons. The pros and cons of using the term σ-aromaticity in chemical discussions are presented.     

Calibration of conductance cells at various temperatures

Precise conductance measurements on aqueous potassium chloride solutions at 0, 10, 18, and 25°C have been made under various conditions over a concentration range 10^?4?2 mole-dm^?3, yielding the conductance equations $$\begin{gathered} 25^\circ C:\Lambda = 149.873 - 95.01\sqrt c + 38.48c log c + 183.1c - 176.4c^{3/2} \hfill \\ 18^\circ C:\Lambda = 129.497 - 80.38\sqrt c + 32.87c log c + 154.3c - 143.0c^{3/2} \hfill \\ 10^\circ C:\Lambda = 107.359 - 64.98\sqrt c + 27.07c log c + 125.4c - 110.3c^{3/2} \hfill \\ 0^\circ C:\Lambda = 81.700 - 47.80\sqrt c + 20.60c log c + 93.8c - 79.3c^{3/2} \hfill \\ \end{gathered} $$ which are proposed for calibration of conductance cells.     

Facile Synthesis and Crystal Structures of New Ammonium Sulfonates （CA-DNBS and TEA-TMBS）

The title compounds, C12HIoN307SCI （I） and C15H27NO3S （II）, crystallize in the monoclinic system, space group P21/c with a = 7.3995（1）, b = 27.8489（6）, c = 9.8246（2）/, fl = 131.349（1）, V = 1519.82（5） A3, Z = 4, F（000） = 768, Rint = 0.033 and S = 1.03 for I, and in the orthorhombic system, space group Pbca with a = 8.6227（1）, b = 16.1480（4）, c = 23.8774（6）/, V= 3324.67（12） A3, Z = 8, F（000） = 1312, Rint = 0.024 and S = 1.04 for II. We have devised a convenient procedure for the synthesis of fused organic salts resulting from 1：1 proton-transfer, using an amine and a derivative ofbenzenesulfonic acid. The synthesized salts have a number of applications ranging from their consumption as eco-friendly solvents and catalysts in organic syntheses, to being used as efficient precursors for the production of sulfa drugs. Structures of compounds 3-chloroanilinium 2,4-dinitrobenzenesulfonate （CA-DNBS） and triethylaminium 2,4,6-trimethylbenzenesulfonate （TEA-TMBS） were determined by single-crystal X-ray diffraction studies and infrared spectroscopy.     

Two Cobalt（II） Complexes Derived from the Hydrolysis Product of Di-Schiff Base Ligand N,N＇-Bis-（1-benzimidazo-2-yl-ethylidene）-ethane-1,2-diamine： Preparation,Characterization and Crystal Structure of the 6-Coordinate Species [CoL2]X·H2O （X =

The reactions of Co（C1O4）2·6H2O and Co（NO3）2.6H2O with the di-Schiff base ligand N,N＇-bis-（1-benzimidazo-2-yl-ethylidene）-ethane-1,2-diamine （LA） in ethanol have been investigated. The reactions of LA with excess amount of cobalt salts yield the six-coordinate complexes [CoL2]（ClO4）E·H2O 1 and [CoL2]（NO3）E·H2O 2 as isolatable products （L= N-（1- benzimidazo-2-yl-ethylidene）-ethane-1,2-diamine）, where L is a tri-dentate mono-Schiff base ligand, resulting from the hydrolysis of the precursor di-Schiff base LA. Both complexes were characterized by X-ray crystallography. Crystal data for complex 1： monoclinic, space group P21/c, a = 11.9214（10）, b = 23.5828（17）, c = 14.0387（12）A, β = 135.219（4）°, C22H30Cl2CoN8O9, Mr = 680.37, V = 2780.1（4） A^3 ,Z = 4, Dc = 1.625 g/cm^3,μ（MoKa） = 0.876 mm^-1, F（000） = 1404, the final R = 0.0725 and wR = 0.1530 for 5726 observed reflections （I 〉 2σ（I））. Crystal data for complex 2： monoclinic, space group P21/c, a = 18.2162（16）, b = 10.0610（6）, c = 18.593（2）A, β = 130.099（3）°, C22H30CoN10O7, Mr = 605.49, V = 2606.5（4） A3 Z = 4, Dc = 1.543 g/cm^3,μ（MoKa） = 0.722 mm^-1, F（000） = 1260, the final R = 0.0619 and wR = 0.1429 for 5194 observed reflections （I 〉 2σ（I））. X-ray diffraction analysis reveals that each cobalt atom in the two complexes is chelated by six nitrogen atoms from two tridentate iigands L, exhibiting a slightly distorted octahedral coordination sphere. In both complexes, the strong hydrogen-bonding interactions between the lattice waters and N-H groups of the ligands result in 1D chains which are further connected by ClO4^- （or NO3^-） groups to form a 3D framework. In complex 2, the strong π-π interactions increase the stability of the structure.     

Through-bond and through-space interactions : The electronic spectrum of barrelene

The first theoretical calculations that reproduce the observed UV spectrum of bairelene are reported. Absorptions above 200 nm are assigned as π →σ^* while the first excitation that is essentially π → π^* is predicted at ca 180 nm. These results are interpreted in terms of through-space π - π interaction, which splits the π-levels, and through-bond interaction, which mixes σ into the π, and fills in the gap between the antibonding π-orbitals. The latter interaction is such that the σ-framework, in each of the three bridges, couples the ethylenic moieties that are based on the other two.     

Syntheses,Crystal Structures,and Properties of a New Lead(Ⅱ) Complex Involving Holo-and Hemidirected Coordination Spheres with 3,5,6-Tris(2-pyridyl)-1,2,4-triazine Ligand

[Pb(TPT)(μ-I)2PbI2(μ-I)2Pb(TPT)] 1(TPT is the abbreviation of 3,5,6-tris(2-pyridyl)-1,2,4-triazine ligand) has been synthesized and characterized by elemental analysis, IR, 1HNMR spectroscopy and studied by thermal and electrochemical properties as well as X-ray crystallography. The single-crystal X-ray data show two different kinds of Pb2+ ions in 1 with coordination numbers of six, Pb1 = PbI6, and five, Pb2 = PbN3I2, with holodirected and hemidirected coordination spheres, respectively. The supramolecular features in 1 are negotiated through the weak but directional Pb···I, C–H···N and C–H···I interactions and aromatic π-π stacking interactions.     

Reactions of Haloarenes with Thiolate Anions in Tetraglyme: Competition between electron transfer and SNAr mechanisms

The reaction of the bromo-substituted naphthalene 1 with the alkanethiolate anions 2a–b and arenethiolate 2c in tetraglyme gave the corresponding 1-naphythyl thio-ethers 3a–c . Thio-ethers 3a–c were oxidized to the corresponding sulfones 4a–c with m- chloroperoxybenzoic acid. The reaction of the dichloro-substituted anthracene 5a with 2b gave the disubstutution product 6a. The reaction of 9-bromoanthracene 5c with the alkanethiolate 2b gave 6b , whereas the reaction of 5c with the arenethiolate 2c gave a mixture of substitution product 6c and anthracene 7. The observation of the formation of both 6c and 7 is explained by the competition between substitution (S_nAr) and electron-transfer (ET) mechanisms. Consistent with this interpretation, the reaction of the monochloro-substituted 5b , which has a higher-energy σ^* orbital, with 2c gave 6c without the formation of 7. Zn/KOH in tetraglyme was shown to reduce the aryl halides 5b–c and thio-ether 6c to 7 .     

Investigation of the Interaction between Isoflavonoids and Bovine Serum Albumin by Fluorescence Spectroscopy

The interactions of bovine serum albumin （BSA） with three structurally related isoflavonoids, genistein, puerarin and daidzein, were studied under physiological conditions by fluorescence spectroscopic technique. The quenching mechanism of these compounds with BSA was suggested as static quenching and the binding constants were determined at different temperatures based on the fluorescence quenching results. The transfer efficiency of energy and distance between the acceptor and BSA were investigated on the basis of the mechanism of the Forster energy transference. According to the thermodynamic parameters it has been suggested that the acting force be mainly hydrophobic force. The comparison of binding potency of the three isoflavonoids to BSA showed that the substitution by 5-OH and 8-Glc could enhance the binding affinity. All these obtained in the work can make us better understand the mode of the action and pharmacological activities of the isoflavonoids.     

Bond length and local energy density property connections for non-transition-metal oxide-bonded interactions

For a variety of molecules and earth materials, the theoretical local kinetic energy density, G(r(c)), increases and the local potential energy density, V(r(c)), decreases as the M-O bond lengths (M = first- and second-row metal atoms bonded to O) decrease and the electron density, rho(r(c)), accumulates at the bond critical points, r(c). Despite the claim that the local kinetic energy density per electronic charge, G(r(c))/rho(r(c)), classifies bonded interactions as shared interactions when less than unity and closed-shell when greater, the ratio was found to increase from 0.5 to 2.5 au as the local electronic energy density, H(r(c)) = G(r(c)) + V(r(c)), decreases and becomes progressively more negative. The ratio appears to be a measure of the character of a given M-O bonded interaction, the greater the ratio, the larger the value of rho(r(c)), the smaller the coordination number of the M atom and the more shared the bonded interaction. H(r(c))/rho(r(c)) versus G(r(c))/rho(r(c)) scatter diagrams categorize the M-O bonded interactions into domains with the local electronic energy density per electron charge, H(r(c))/rho(r(c)), tending to decrease as the electronegativity differences for the bonded pairs of atoms decrease. The values of G(r(c)) and V(r(c)), estimated with a gradient-corrected electron gas theory expression and the local virial theorem, are in good agreement with theoretical values, particularly for the bonded interactions involving second-row M atoms. The agreement is poorer for shared C-O and N-O bonded interactions.     

Synthesis,Anti‐Microbial,and Cytotoxic Activities Evaluation of Some New Pyrido[2,3‐d]Pyrimidines

Novel pyridine derivatives 1d and 7 , pyrido[2,3‐d]pyrimidine derivatives 2a , 2b , 2c , 2d , 3a , 3b , 3c , 3d , 4a , 4b , 4c , 4d , 5a , 5b , 5c , 5d , 6a , 6b , 6c , 6d , 8a , 8b , and 9a , 9b were synthesized and screened for their anti‐microbial and cytotoxic activities. Compounds 2b , 2c , 3b , 3c , 5b , 5c , 6b , 6c , and 7 showed excellent anti‐microbial activities against all the tested bacteria and fungi compared to the reference drugs. Furthermore, they exhibited high safety profile in cytotoxicity test except 2c and 3c . The structures of the newly synthesized compounds were confirmed by spectral data and elemental analysis.     

Synthesis,Crystal Structure and Biological Activity of Diethyl 1,4-dihydro-2,6-dimethyl-4-（4-methyl-1,2,3-thiadi azol-5-yl） pyridine-3,5-dicarboxylate

The title compound diethyl 1,4-dihydro-2,6-dimethyl-4-(4-methyl-1,2,3-thiadiazol-5-yl) pyridine-3,5-dicarboxylate(C16H21N3O4S, Mr = 351.42) was prepared by the Hantszch reaction with 4-methyl-1,2,3-thiadiazole-5-formaldehyde, ethyl acetoacetate and ammonium acetate in the presence of aluminum chloride in alcohol, and its structure was characterized by IR spectra, 1H-NMR, EA, and single-crystal X-ray diffraction. The crystal of the title compound belongs to monoclinic system, space group P21/n with a = 11.300(2), b = 12.771(3), c = 12.826(3) ?, β = 96.55(3)o, V = 1839.0(6) ?3, Z = 4, Dc = 1.296 g/cm3, μ(MoKa) = 0.71073 mm-1, F(000) = 744, R = 0.0981 and wR = 0.1994. X-ray diffraction result shows that the torsion angles of N(1)–C(2)– C(3)–C(4) and C(2)–C(3)–C(4)–C(8) are 178.9(3)° and –130.3(3)°, respectively. All rings in the title compound are non-planar. The bioassay results indicate that the title compound has good fungicidal activity, good antivirus activity against tobacco mosaic virus and certain extent of insecticidal activity against Mythimna separata.     

New beta-lactam antibiotics. Functionalisation of the cephem 3-position with sulfur or nitrogen bearing substituents (author's transl)]

New β-lactam antibiotics. Functionalisation of the cephem 3-position with sulfur or nitrogen bearing substituents The tosylate sulfoxides or mesylates derived from the 3-hydroxy-ceph-3-em esters 1a, b reacted with thiols to give 3-thioethers which were converted into the microbiologically active acids 7a, c, 8a, c 9c, and 13c by known procedures. The 3-methylsulfonyl-derivative 17c was prepared from 6b. The synthesis of the 3-acylamino-ceph-3-em-4-carboxylic acids 23c and 24c is reported.     

Laser Flash Photolysis on Electron Transfer Reactions between 1,8-Dihydroxyanthraquinone with Adenine and Cytosine

Electron transfer （ET） reactions between 1,8-dihydroxyanthraquinone （DHAQ） and two DNA bases, adenine （A） and cytosine （C）, have been investigated in CH3CN/H20 solution with nanosecond time-resolved laser flash photolysis. After irradiation at 355 nm, the triplet DHAQ is produced via intersystem crossing and reacts with two nucleobases. ET processes for both reactions have been definitely identified, in which two bases play a significant role of electron donor. Based on the measured decay dynamics of various intermediates and the corresponding quenching rates, an initial ET process followed by a secondary proton-transfer reaction is suggested for both the overall reactions. By plotting the observed quenching rate against the concentration of two DNA bases, the bimolecular quenching rate constants are determined as 9.0-10s L/（mol.s） for the 3DHAQ＊＋C reaction and 3.3x10^8 L/（mol.s） for the 3DHAQ＊＋A reaction, respectively.