含能配合物[Zn(DAT)_6](ClO_4)_2 (DAT=1,5-二氨基四唑)的合成、晶体结构及性质

采用直接法合成了新型高氮含能配合物[Zn(DAT)6](ClO4)2(DAT=1,5-二氨基四唑),并用元素分析、傅立叶变换红外光谱对其结构进行了表征.利用缓慢蒸发溶剂法培养出其单晶,采用X射线单晶衍射仪测定其晶体结构,结果表明该晶体属于三方晶系,P3空间群,a=b=1.18398(9)nm,c=0.65700(10)nm,γ=120°,V=0.79760(15)nm3,Z=1.在目标配合物的最小不对称单元中有1个Zn2+,6个DAT分子和2个ClO-4.来自6个DAT分子的6个N原子分别与中心Zn2+配位,形成一个六配位、非中心对称的畸变八面体结构.用差示扫描量热分析、热重-微分热重分析结合红外光谱研究了标题化合物的热分解机理以及分解反应动力学参数.测定了标题配合物的感度性能,结果表明标题配合物具有一定的摩擦感度.     

Suppression of mesoscopic order by complementary interactions in supramolecular polymers

We show here that complementary interactions can suppress mesoscopic order and thus lead to a counterintuitive change in material properties. We present results for telechelic supramolecular polymers based on poly(propylene oxide) (PPO), thymine (Thy), and diaminotriazine (DAT). The self-complementary systems based on Thy exhibit lamellar order and 2D crystallization of Thy in the bulk. We show that the microphase segregation is inhibited by addition of DAT: the strong complementary Thy-DAT interaction inhibits crystallization of thymine in microdomains and lamellar structuration. As a result, the supramolecular polymer with only weakly self-complementary stickers is a solid, whereas the supramolecular polymer with strongly complementary stickers is a liquid.     

含能配合物[Zn(DAT)6](ClO4)2(DAT＝1,5-二氨基四唑)的合成、晶体结构及性质

采用直接法合成了新型高氮含能配合物[Zn(DAT)₆](ClO₄)₂(DAT＝1,5-二氨基四唑), 并用元素分析、傅立叶变换红外光谱对其结构进行了表征. 利用缓慢蒸发溶剂法培养出其单晶, 采用X射线单晶衍射仪测定其晶体结构, 结果表明该晶体属于三方晶系, 空间群, a＝b＝1.18398(9) nm, c＝0.65700(10) nm, γ＝120°, V＝0.79760(15) nm³, Z＝1. 在目标配合物的最小不对称单元中有1个Zn^2＋, 6个DAT分子和2个. 来自6个DAT分子的6个N原子分别与中心Zn^2＋配位, 形成一个六配位、非中心对称的畸变八面体结构. 用差示扫描量热分析、热重-微分热重分析结合红外光谱研究了标题化合物的热分解机理以及分解反应动力学参数. 测定了标题配合物的感度性能, 结果表明标题配合物具有一定的摩擦感度.     

Crystal Structure,Thermal Decomposition Behaviors and Sensitivity Properties of a Novel Energetic Compound [Co(DAT)6](ClO4)2

A novel energetic coordination compound [Co(DAT)₆](ClO₄)₂ has been synthesized by using 1,5‐diaminotetrazole (DAT) as a ligand and its structure has been characterized using X‐ray single crystal diffraction, elemental analysis and FT‐IR spectroscopy. The central cobalt(II) cation is coordinated by six N atoms from six DAT molecules to form a six‐coordinated and distorted octahedral structure. Di‐dimension layer structure was formed by the extensive intermolecular hydrogen bonds between DAT ligands and ClO^?₄ anions along a‐axis and b‐axis. Thermal decomposition mechanism of [Co(DAT)₆](ClO₄)₂ was investigated based on differential scanning calorimetry (DSC), thermogravimetric analysis (TGA) and Fourier transform infrared (FT‐IR) spectra. The kinetic parameters of the first exothermic process were studied by applying the Kissinger's and Ozawa‐Doyle's methods. Additionally, the sensitivities of this complex were tested. The results of all the studies show that [Co(DAT)₆](ClO₄)₂ has an extreme potential application as an energetic material.     

含能配合物[Mn(DAT)6](ClO4)2的合成、晶体结构、热行为及感度性质

合成了新型含能配合物[Mn(DAT)6](ClO4)2(DAT=1,5-二氨基四唑), 用X射线单晶衍射法测定了其晶体结构. 该晶体属三方晶系, P3c1空间群, a=b=1.18435(17) nm, c=1.3081(3) nm, α=β=90°, γ=120°, V=1.5891(5) nm3, Z=2. 该配合物分子结构单元中有1个Mn2+离子、6个DAT分子和2个ClO4-离子. 由6个DAT分子中的6个N原子与中心Mn2+离子配位形成六配位、非中心对称的畸变八面体结构. 利用元素分析、差示扫描量热分析(DSC)、热重-微分热重分析(TG-DTG)等方法进行了表征, 研究了其感度性能. 研究结果表明, 该配合物对外界刺激具有很高的响应性和危险性.     

End-to-end single cyanato and thiocyanato bridged Cu(II) polymers with a new tridentate Schiff base ligand: crystal structure and magnetic properties

A new tridentate Schiff base ligand HL (L = C14H19N2O), derived from the condensation of benzoylacetone and 2-dimethylaminoethylamine in a 1:1 ratio, reacts with copper(ii) acetate and cyanate, thiocyanate or azide, to give rise to several end-to-end polymeric complexes of formulae [CuL(mu(1,3)-NCO)]n 1, [CuL(mu(1,3)-NCS)]n 2 and the complex 3 has two crystallographically independent units of formula [CuL(N3)] in the asymmetric unit cell. Complex 3 exists in dimeric form rather than as a polymeric chain. Compound 1 is the first report of a singly end-to-end cyanate bridged polymeric chain of Cu(II) with a Schiff base as a co-ligand. There are many examples of double NCS bridged polymeric chains, but fewer singly bridged ones such as compound 2. We have characterized these complexes by analytical, spectroscopic, structural and variable temperature magnetic susceptibility measurements. The coordination geometry around the Cu(II) centers is distorted square pyramidal for 1 and 2 and square planar for complex 3. The magnetic susceptibility data show slight antiferromagnetic coupling for the polymers having J values -0.19 and -0.57 cm(-1) for complexes 1 and 2 respectively. The low values of J are consistent with the equatorial-axial disposition of the bridges in the polymers.     

The functional domains of dopamine transporter for cocaine analog, CFT binding

Cocaine analogue, CFT (2beta-carbomethoxy-3beta-(4-fluorophenyl) tropane) binding to dopamine transporter (DAT) in different species is quite heterogeneous. CFT is scarcely detected in bovine DAT whereas it is conspicuous in humans. To examine the structural basis for this functional discrepancy, we analyzed transporter chimeras of these two DATs. The CFT binding activities are avid in all of the chimeric DATs of which both of the 3rd and the 6-8th transmembrane domain (TM) are composed of human DAT sequences. On the contrary, CFT binding activities were scarcely detected if either or both of two regions are replaced with bovine sequences. These findings indicate that the CFT binding absolutely requires human DAT sequences, at least, in the regions encompassing the 3rd and 6-8th transmembrane domain (TM), and that these regions might contribute to form the 3-dimensional pocket for CFT binding.     

3,6-二叠氮基-1,2,4,5-四嗪的合成及理论研究

以3,6-双(3,5-二甲基吡唑基)-1,2,4,5-四嗪为原料, 经过肼解反应和重氮化反应, 制得了3,6-二叠氮基-1,2,4,5-四嗪(DAT). 在DFT-B3LYP/6-31G*水平下求得了DAT的分子几何、IR光谱和热力学性质. 计算模拟IR光谱和实测IR光谱的对比表明DAT在固态下不发生叠氮-四唑互变异构反应. 根据IR光谱计算了DAT的热容、焓、熵等热力学参数, 也给出了这些参数和温度T之间的函数关系. 在不破坏四嗪环和叠氮基的原则下通过构建等键反应求得了DAT的精确生成热为1088 kJ•mol^—1. 爆轰性能计算表明DAT爆速D＝8.45 km•s^－1, 爆压P＝31.3 GPa, 高于TNT和HMX.     

Two Novel Nitrogen-rich Energetic Coordination Compounds M_2（DAT）_5（H_2O）_3（TNR）_2（M = Zn and Co）：Synthesis,Characterization,Thermal Properties and Sensitivity

Two novel energetic coordination compounds Zn2(DAT)5(H2O)3(TNR)2 and Co2(DAT)5(H2O)3(TNR)2 were synthesized and their structures were characterized by elemental analysis and FT-IR spectroscopy.The crystal structures were determined by single-crystal X-ray diffraction.The results reveal that the compounds have similar molecular structures and the crystals belong to the triclinic system,space group P with a = 11.491(3),b = 13.564(3),c = 15.496(3) ,V = 2180.4(8) 3,C17H28 Zn2N36O19,Mr = 1203.02 g·mol-1,Dc = 1.832 g·cm-3,μ(MoKα) = 1.221 mm-1,F(000) = 1223,Z = 2,R = 0.0596 and wR = 0.1514 for 11289 observed reflections(I > 2σ(I)) for Zn2(DAT)5(H2O)3(TNR)2 and a = 11.5291(13),b = 13.4894(15),c = 15.4852(17) ,V = 2164.8(4) 3,C17H28Co2N36O19,Mr = 1190.14 g·mol-1,Dc = 1.826 g·cm-3,μ(MoKα) = 0.888 mm-1,F(000) = 1211,Z = 2,R = 0.0576 and wR = 0.1431 for 11218 observed reflections(I > 2σ(I)) for Co2(DAT)5(H2O)3(TNR)2,respectively.The thermal decomposition characteristics of the com-pounds were investigated using differential scanning calorimetry and thermal gravimetry-diffediffer-rential thermal gravimetry.The results of thermal decomposition processes were similar for the two compounds.Both undergo four-step decomposition after the loss of coordinated H2O molecules.The final solid residues for the two DAT complexes were the corresponding metal oxides.The kinetic parameter of the first exothermic process of the compounds was studied by applying the Kissinger and Ozawa-Doyle methods.The thermodynamic parameters of the activation could be calculated.Sensitivity tests revealed that Co2(DAT)5(H2O)3(TNR)2 was more sensitive than Zn2(DAT)5(H2O)3(TNR)2.     

Modular Construction of Porous Hydrogen-Bonded Molecular Materials from Melams

Ordered materials with predictable structures and properties can be made by a modular approach, using molecules designed to interact with neighbors and hold them in predetermined positions. Incorporating 4,6-diamino-1,3,5-triazin-2-yl (DAT) groups in modules is an effective way to direct assembly because each DAT group can form multiple N−H⋅⋅⋅N hydrogen bonds according to established patterns. We have found that modules with high densities of N(DAT)₂ groups can be made by base-induced double triazinylations of readily available amines. The resulting modules can form structures held together by remarkably large numbers of hydrogen bonds per molecule. Even simple modules with only 1–3 N(DAT)₂ groups and fewer than 70 non-hydrogen atoms can crystallize to form highly open networks in which each molecule engages in over 20 N−H⋅⋅⋅N hydrogen bonds, and more than 70 % of the volume is available for accommodating guests. In favorable cases, guests can be removed to create rigorously porous crystalline solids analogous to zeolites and metal–organic frameworks.     

Modeling of bovine type-I collagen fibrils: interaction with pickling and retanning agents

Bovine Type I collagen was investigated, building on a large scale computer model of a collagen fibril in water, and focusing on two stages of the leather manufacturing process. The effects of different salts (NaCl, CaCl(2), and Na(2)SO(4)) on the swelling behavior of collagen at low pH (the pickling process) were studied. The salts suppress the swelling of the fibrils at low pH and we find specific stabilizing influences for CaCl(2) and Na(2)SO(4), due to weak Ca(2+)/Cl(-) and strong SO(4) (2-)/lysine/arginine interactions, respectively. Using state-of-the-art sampling techniques, such as the metadynamics algorithm, to allow an efficient exploration of configuration space, we were able to investigate the effect of polyacrylate and poly(methyl acrylate) - two polymeric retanning agents - on the fibril. Both polymers interact with the ammonium groups on the surface, but polyacrylate shows significantly stronger interactions. We suggest that it is this stronger interaction that contributes to the reduced suitability of PAA as a tanning agent.     

Polymer complexes. LVIII. Structures of supramolecular assemblies of vanadium with chelating groups

Oxovanadium(IV) polymer complexes of formulation {[(VO)L](2)}(n) (1) and [(VO)LB](n) (2-4), where H(2)L is tridentate and dianionic ligand (allylazorhodanine) and B is planar heterocyclic and aliphatic base have been prepared and characterized by elemental analyses, IR, (1)H NMR, electronic spin resonance spectra, magnetic susceptibility measurements, molar conductance and thermal studies. The molecular structure shows the presence of a vanadyl group in six-coordinate VNO(3)/VN(3)O(3) coordination geometry. The N,N-donor heterocyclic and aliphatic bas displays a chelating mode of binding with an N-donor site trans to the vanadyl oxo-group. In all polymeric complexes (1-4) the ligand coordinates through oxygen of phenolic/enolic and azodye nitrogen. The molar conductivity data show them to be non-electrolytes. All the polymer complexes are ESR active due to the presence of an unpaired electron. The calculated bonding parameters indicate that in-plane σ bonding is more covalent than in-plane π bonding. From the electronic, magnetic and ESR spectral data suggest that all the oxovanadium(IV) polymer complexes have distorted octahedral geometry. The thermal decomposition process of the polymeric complexes involves three decomposition steps.     

Spin crossover in polymeric and heterometallic FeII species containing polytopic dipyridylamino-substituted-triazine ligands

We report the synthesis and characterisation of the new polytopic ligands, ddta (N,N-di(pyridin-2-yl)-4,6-di(1,4,7,10-tetraoxa-13-azacyclopentadecan-13-yl)-1,3,5-triazin-2-amine) and tptd (N(2),N(2),N(4),N(4)-tetra(pyridin-2-yl)-6-(1,4,7,10-tetraoxa-13-azacyclopentadecan-13-yl)-1,3,5-triazine-2,4-diamine). Each contains N-donor dipyridylamino binding sites as well as separate and distinct mono-aza-15-crown-5 binding sites. The ligand ddta has been used to synthesise the polymeric heterometallic SCO compound trans-[Fe(II)(NCS)(2)(ddta)(2)Na(2)](ClO(4))(2)·4CH(3)CH(2)CH(2)OH, 1, and tptd has been used to synthesise the polymeric SCO compound trans-[Fe(II)(NCS)(2)(tptd)]·CH(3)OH, 2, and the dinuclear compound cis-[(Fe(II))(2)(NCS)(4)(tptd)(2)], 3. Magnetic susceptibility measurements show that 1 and a desolvated sample of 2 each undergo a gradual, one-step spin transition with T(?) values of ~240 K and ~110 K, respectively. The paucity of inter-chain intermolecular interactions, as well as the flexible, covalent bridges between Fe(II) spin crossover sites, are likely to contribute to the gradual nature of the spin transition observed in each case. Variable temperature powder X-ray diffraction studies on 1 show the anisotropic behaviour of the unit cell parameters, where c and the b-c plane are most affected by structural changes occurring as the temperature is lowered.     

PREPARATION AND MAGNETIC PROPERTIES OF POLYMERIC COMPLEXES CONTAINING 1,10-PHENANTHROLINE

A series of polymeric complexes were prepared from Fe~(2 ),Co~(2 ) or Ni~(2 ) and poly(Schiff base)(DAPcIPA), which was obtained by polycondensation of 5,6-diamino-1,10-phenanthroline(DAP)with isophthalaldehyde(IPA).The structures of the polymer and the polymeric complexes were characterized by IR,~1H-NMR and elemental analysis.The magnetic behavior of these complexes was measured as a function of magnetic field strength(0-3.98×10~6 A/m)at 5 K and as a function of temperature(5-300 K)at a magnetic field strength of 2.39×10~6 A/m.Experimental results show that DAPcIPA-Ni~(2 ),DAPcIPA-Co~(2 ) are soft ferromagnets while DAPcIPA-Fe~(2 ) exhibits features of an antiferromagnet.     

Development of asymmetric 6FDA-2,6DAT hollow fiber membranes for CO2/CH4 separation: Part 2. Suppression of plasticization

We have studied the CO₂-induced plasticization phenomenon of asymmetric poly(2,6-toluene-2,2-bis(3,4-dicarboxyphenyl) hexafluoropropane diimide) (6FDA-2,6 DAT) hollow fiber membranes for CO₂/CH₄ applications. Several processing and thermal approaches have been investigated to study their effectiveness to enhance anti-plasticization characteristics. Experimental results indicate that hollow fiber membranes spun at different shear rates and take-up rates cannot effectively suppress the CO₂ induced plasticization. Thermally treated 6FDA-2,6 DAT hollow fiber membranes show significant reduction in CO₂-induced plasticization. Wide-angle XRD spectra reveal no visible change in d-space after thermal treatment, while solubility data imply no cross-links occurred. Scanning electron microscopy (SEM) pictures illustrate heat treatment results in more compact selective-skin layer and substructure, thus strengthening the anti-plasticization characteristics of hollow fibers. By considering the degree of plasticization, dense-layer thickness, and heat treatment temperature, an optimal temperature of 250 °C (for 5 min) is identified for the heat treatment of 6FDA-2,6 DAT hollow fiber membranes. NMR spectra suggest the cause of forming a highly densified skin after heat treatment is mainly due to chain relaxation and enhanced nodule interaction at elevated temperatures.     

Full-field photonic biosensors based on tunable bio-doped sol-gel glasses

A full-field generic photonic biosensor approach, which relies on a bio-doped polymeric strip waveguide configuration, is described. We show the potential of tailor-made hybrid polymeric materials prepared by sol-gel technology for the fabrication of ultra-compact biosensor devices, where both the transducer and the recognition elements are merged into one single microstructure. Such devices were fabricated by micromolding in capillaries (MIMIC) soft lithographic technique. In contrast to evanescent field sensors, the sensor response does not only rely on the interaction of the evanescent wave with the recognition element, but on the interaction of the whole field, thus enabling a reduction of the sensor dimensions and/or a decrease of its limit of detection (LOD). The potential of this generic approach was demonstrated by developing a biosensor for the detection of H(2)O(2) using horseradish peroxidase (HRP) as the doping agent. Solutions containing 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic) acid (ABTS) and different concentrations of H(2)O(2) were dispensed over the waveguide and the green-coloured cation radical ABTS*(+) product was mainly obtained inside the photonic structure, resulting in a maximum absorption increase of 2.5 a.u. at a set working wavelength of 670 nm over the H(2)O(2) concentration range studied. The sensor exhibited a sensitivity of (3.1+/-0.2) x 10(3) a.u./mol L(-1) and a limit of detection (LOD) of 4.4 x 10(-5) mol L(-1) H(2)O(2). These results anticipate that full-field waveguide microstructures based on bio-doped sol-gel polymers will enable the fabrication of cost-effective photonic biosensors. Moreover, the ease of fabrication by a soft lithography technique and the use of such polymeric materials are fully compatible with their integration in compact automatic analysis systems.     

13C, 25Mg and 11B solid-state NMR study of a fire retarded ethylene-vinyl acetate copolymer

Flame retardance of ethylene-vinyl acetate copolymer (EVA) can be achieved using magnesium hydroxide (Mg(OH)₂) incorporated in the polymeric matrix. The adduct of small amount of zinc borate as synergistic agent in the formulation increases the fire-proofing properties. Multinuclei solid-state NMR appears as a powerful means to characterise materials before and after combustion. We show that endothermic dehydration, water vapour evolved and formation of a glassy coating provide the flame retardancy of interest to the polymeric matrix.     

A flow cytometry-based dopamine transporter binding assay using antagonist-conjugated quantum dots

Here we present the development and validation of a flow cytometry-based dopamine transporter (DAT) binding assay that uses antagonist-conjugated quantum dots (QDs). We anticipate that our QD-based assay is of immediate value to the high throughput screening of novel DAT modulators.     

Synthesis and Characterization of a Novel Energetic Complex [Cd(DAT)6](NO3)2 (DAT = 1,5‐diamino‐tetrazole) with High Nitrogen Content

The novel high nitrogen‐containing energetic complex [Cd(DAT)₆](NO₃)₂ was synthesized by reaction of Cd(NO₃)₂·6H₂O with 1,5‐diamino‐tetrazole (DAT). It was characterized by elemental analysis, FT‐IR spectroscopy and single‐crystal X‐ray diffraction analysis. The central Cd²⁺ ion is coordinated by six nitrogen atoms from six DAT ligand molecules to form a hexacoordinate distorted octahedral compound. The [Cd(DAT)₆](NO₃)₂ molecules are linked together through two types of hydrogen bonds thus forming a stable three‐dimensional net structure. The thermal decomposition mechanism of [Cd(DAT)₆](NO₃)₂ was investigated by DSC and TG/DTG analyses and FT‐IR spectroscopy. The kinetic parameters of the exothermic process were studied by using Kissinger’s and Ozawa–Doyle’s methods.     

Thermo/pH Dual Responsive Mixed‐Shell Polymeric Micelles Based on the Complementary Multiple Hydrogen Bonds for Drug Delivery

Thermo/pH dual responsive mixed‐shell polymeric micelles based on multiple hydrogen bonding were prepared by self‐assembly of diaminotriazine‐terminated poly(?‐caprolactone) (DAT‐PCL), uracil‐terminated methoxy poly(ethylene glycol) (MPEG‐U), and uracil‐terminated poly(N‐vinylcaprolactam) (PNVCL‐U) at room temperature. PCL acted as the core and MPEG/PNVCL as the mixed shell. Increasing the temperature, PNVCL collapsed and enclosed the PCL core, while MPEG penetrated through the PNVCL shell, thereby leading to the formation of MPEG channels on the micelles surface. The low cytotoxicity of the mixed micelles was confirmed by an MTT assay against BGC‐823 cells. Studies on the in vitro drug release showed that a much faster release rate was observed at pH 5.0 compared to physiological pH, owing to the dissociation of hydrogen bonds. Therefore, the mixed‐shell polymeric micelles would be very promising candidates in drug delivery systems.