Synthesis,Crystal Structure and Biological Activity of a Novel Complex:Co(L)_2(CH_3OH)_2Cl_2 (L=3-(1,2,4-Triazole-yl)-6-chloro-pyridazine)

The title compound, Co（L）2（CH3OH）2Cl2 （L = 3-（1,2,4-triazole-yl）-6-chloro-pyridazine） 1, has been synthesized and its crystal structure has been determined by X-ray analysis. Complex 1 crystallizes in the triclinic system, space group P1 with a = 6.018（3）, b = 9.832（5）, c = 9.921（5）A, a = 78.270（8）, β = 74.550（8）, γ = 83.807（8）°, V = 553.1（5）A^3, Z = 1, C14H16Cl4CoN10O2, Mr = 557.10, Dc = 1.673 g/cm^3, F（000） = 281,μ（MoKα） = 1.293 mm^-1, the final R = 0.0453 and wR = 0.1181 for 1539 observed reflections with I 〉 2σ（I）. The Co（II） ion is in a distorted centrosymmetric six-coordinate octahedral environment with two Ntriazole, two Omethanol and two Cl atoms. Via hydrogen bonds the configuration of 1 has been extended into 1D chains which are developed to 2D layers via π-π sticking action, and these layers are further extended into a 3D network by hydrogen bonds. The antibacterial activity of the title compound has been detected, and the results show that the ligands and cobalt（II） complex exhibit certain fungicidal activity against several bacteria. Furthermore, the spectral properties of the title compound have been also studied and discussed.

Theoretical Study on the Mechanism of a New Synthesis Reaction of 1,3,5-Substituted-1,2,4-triazoles by Carboxylic Acids,Amidines,and Hydrazines

The synthesis of 1,3,5-substituted-1,2,4-triazoles from α-imino-3-pyridine formic acid,acetamidine and anisole hydrazine as a model reaction in this paper and the synthesis mechanism of 1,3,5-substituted-1,2,4-triazole compounds from carboxylic acids,amidines and hydrazines have been first investigated with the B3 LYP/6-311＋＋G＊＊ method.According to the potential energy profile,it can be predicted that the course of the reaction consists of five reactions containing six elementary reactions.The α-imino-3-pyridine formic acid and acetamidine form first an intermediate product through a dehydration reaction; the intermediate product further combines with hydrogen ion to form a positive ion; the positive ion reacts with anisole hydrazine by a dehydration reaction to form another positive ion; then,followed by two isomerization reactions,the final reaction with the acetate ion（Ac-） produces the final product.The research results reveal the laws of synthesis reaction of 1,3,5-substituted-1,2,4-triazoles by the carboxylic acids,amidines,hydrazines and their derivatives on theoretical level.It provides the systemic theoretical basis for the synthesis,development and application of 1,3,5-substituted-1,2,4-triazole compounds.

Thermodynamic Study and Spectroscopic Analysis of a Charge-Transfer Complex between 3,5-Diamino-1,2,4-Triazole and 6-Methyl-1,3,5-Triazine-2,4-Diamine with Chloranilic Acid

Studying of charge-transfer (CT) and proton transfer interactions is essential due to their important role in many biological field and industrial applications. The current work will add more information’s about the nature of interaction between 3,5-diamino-1,2,4-triazole (DAT) and 6-methyl-1,3,5-triazine-2,4-diamine (MTDA) with 3,6-dichloro-2,5-dihydroxy-p-benzoquinone (chloranilic acid CLA) which was studied spectrophotometrically in Ethanol (EtOH) and Methanol (MeOH) solvents at different temperatures. The molecular composition of the formed complexes was studied by applying continuous variation and spectrophotometric titration methods and found to be 1:1 charge transfer complex for both Complex (DAT:CLA) and (MTDA:CLA) which are produced. Minimum-Maximum absorbance’s method has been applied to calculate the formation constant KCT and molecular extinction coefficient (ε);they recorded high values confirming high stability of the produced complexes. Oscillator strength (f), transition dipole moment (μ), ionization potential (IP) and dissociation energy (W) of the formed CT-complexes were also determined and evaluated;they showed solvent dependency. It is concluded that the formation constant (KCT) of the complexes is found to depend on the nature of both electron acceptor and donors and on the polarity of solvents.

Synthesis and plant-growth regulatory activities of novel imine derivatives containing 1H-1,2,4-triazole and thiazole rings

Eleven new imine derivatives 6 containing 1H-1,2,4-triazole and thiazole rings were synthesized by the condensation of 5-((1H- 1,2,4-triazol-1-yl)methyl)-4-tert-butylthiazol-2-amine with various substituted benzaldehydes.The structures of the title compounds were characterized by ~1H NMR,MS and elemental analysis.The plant-growth regulatory activities of these compounds were evaluated.The primary bioassay results indicated that these target compounds exhibited promising plant-growth regulatory activities.

Synthesis, Crystal Structure, Fluorescent Property and DFT Calculations of a New Zn(Ⅱ) Complex Based on 3-(2-Pyridyl)-5-(4-pyridyl)-1H-1,2,4-triazole

A new coordination compound Zn（2,4＇-bpt）2（H2O）（1） based on the versatile ligand 2,4＇-Hbpt（2,4？-Hbpt = 3-（2-pyridyl）-5-（4-pyridyl）-1H-1,2,4-triazole） was prepared by hydrothermal reactions. The structure of complex 1 has been characterized by X-ray single-crystal diffraction, elemental analysis, X-ray powder diffraction, IR spectrum analysis and thermogravimetric analysis. Single-crystal X-ray diffraction analysis indicates that the complex belongs to monoclinic system, space group C2/c with a = 23.877（3）, b = 0.7483（9）, c = 1.2492（2） A, b = 92.681（2）°, V = 2230.6（4） A^3, Z = 4, Dc = 1.572 g/cm^3, m = 1.143 mm^-1, Mr = 527.85 and F（000） = 1080. The final R = 0.0581 and wR = 0.0898 with I 〉 2s（I）. 1 is a 0D motif which is connected by hydrogen bonds to form a corrugated 1D pattern. In addition, 1 shows strong photoluminescent emissions in the solid state at room temperature which can be used as potential optical materials. Theoretical calculations based on density functional theory（DFT） were employed in order to explicate the stability and chemical reactivity of 2,4＇-Hbpt with different conformations. The results indicated that conformation I is more stable and prior to coordination in the reactions.

Two New Metal-organic Frameworks Constructed from 3,4,5-Substituted-1,2,4-Triazole Ligands

Two new complexes,[Zn（L1）2（SCN）2]·H2O（1,L1 = 3,5-dimethyl-4-p-tolyl-4H1,2,4-triazole and [Cd3（L2）6（SCN）6]（2,L2 = 3,5-dimethyl-4-phenyl-4H-1,2,4-triazole）,have been hydrothermally prepared and characterized by single-crystal X-ray diffraction,IR spectroscopy,elemental analysis and PXRD.Complex 1 crystallizes in monoclinic,space group P21 /n with a = 11.246（13）,b = 9.640（11）,c = 26.13（3）,β = 100.97（3）,V = 1108.5（3） 3,Z = 4,C24 H28 N8 OS2 Zn,Mr = 572.02,Dc = 1.366 g/cm3,μ = 1.065 mm-1,S = 0.992,F（000） = 1184,the final R = 0.0602 and wR = 0.1700 for 2925 observed reflections（I 2σ（I））.Complex 2 crystallizes in triclinic,space group P1 with a = 11.6669（3）,b = 12.0957（2）,c = 14.3674（3）,α = 105.380（3）,β = 91.020（2）,γ = 92.4100（10）o,V = 1952.30（7）3,Z = 1,C66H66N24S6Cd3,Mr = 1725.08,Dc = 1.467 g/cm3,μ = 1.025 mm-1,S = 1.037,F（000） = 870,the final R = 0.0336 and wR = 0.0946 for 7819 observed reflections（I 2σ（I））.In the title complexes,complex 1 is a mononuclear molecule where the centre Zn（II） coordinates to two 3,4,5-substituted 1,2,4-triazole ligands（L1） and two terminal SCN-anions in a tetrahedral environment while six-coordinated centre Cd（II） atoms with octahedral geometry in complex 2 are bridged by virtue of substituted 1,2,4-triazole（L2） in N1,N2-bridging mode and μ2-N,N-SCN-anions into a trinuclear molecule.

Catalytic Kinetic on the Thermal Decomposition of Ammonium Perchlorate with a New Energetic Complex Based on 3,5-Bis(3-pyridyl)-1H-1,2,4-triazole

A new energetic complex,[Co（3,3？-Hbpt）（Htm）]·H_2O（1,3,3？-Hbpt = 3,5-bis（3-pyridyl）-1H-1,2,4-triazole and H_3tm = trimesic acid）,has been synthesized by hydrothermal reactions and characterized by single-crystal X-ray diffraction,elementary analysis,IR spectroscopy,thermogravimetric analysis and X-ray powder diffraction. Single-crystal X-ray diffraction indicates that the complex belongs to triclinic system,space group P 1 with a = 10.0911（1）,b = 10.2573（1）,c = 10.6393（1） ？,α = 103.793（2）,β = 101.041（2）,γ = 107.918（3）o,V = 974.9（2） ？~3,Z = 2,D_c = 1.732 g·cm-3,μ = 0.941 mm^（-1）,M_r = 508.31,F（000） = 518,the final R = 0.0523 and wR = 0.0935 with I 〉 2σ（I）. In the title complex,Co（Ⅱ） ions are connected by Htm2-anions generating 1D ladder-like chains which are linked by 3,3？-Hbpt to form 1D cages. In addition,the thermal decomposition of ammonium perchlorate（AP） with complex 1 was explored by differential scanning calorimetry（DSC）. AP is completely decomposed in a shorter time in the presence of complex 1,and the decomposition heat of the mixture is 2.531 kJ·g^（-1）,significantly higher than that of pure AP. By Kissinger＇s method,the ratio of Ea/ln（A） is 11.05 for the mixture,which indicates that complex 1 shows good catalytic activity toward the AP decomposition.

Syntheses, Structures, and Luminescence Properties of Two New Open-framework Zinc Phosphites Based on 1,2,4-Triazole Derivatives

With 1,2,4-triazole derivatives as structure directing agents, two new openframework zinc phosphites, [Zn（atrz）（HPO3）]n（1） and [Zn（dmatrz）（HPO3）]n（2）（atrz = 4-amino-1,2,4-triazole, dmatrz = 4-amino-3,5-dimethyl-1,2,4-triazole） have been synthesized and characterized by elemental analysis, IR spectroscopy, thermogravimetric analysis, powder and single-crystal X-ray diffractions. Both compounds are isostructure and crystallize in the P21/c space group of monoclinic system. Compound 1： a = 9.629（1）, b = 7.384（1）, c = 10.274（1） A, β = 110.729（3）°, V = 683.26（2） A^3, Z = 4, Mr = 229.44, Dc = 2.230 g/cm^3, F（000） = 456, S = 1.10, μ = 3.79 mm^（–1）, R = 0.0181 and w R = 0.0466 for 1121 observed reflections（（40） 〉 2s（（40）））. Compound 2： a = 10.786（2）, b = 8.921（1）, c = 9.749（1） A, β = 107.3°, V = 895.6（3） A^3, Z = 4, Mr = 257.49, Dc = 1.910 g/cm^3, F（000） = 520, S = 1.00, μ = 2.90 mm^（–1）, R = 0.018 and wR = 0.051 for 1581 observed reflections（（40） 〉 2s（（40）））. Both compounds are built up into 4.8-net 2D open-frameworks of vertex-linked Zn O4 and HPO3 units（3.57 × 4.53 A^2 for 1 and 4.43 × 5.90 A^2 for 2）. The structures consist of left-, right-handed helical chains that are connected through oxygen atoms to form an undulated 2D sheet stack, which can be topologically regarded as 4.8~2 nets. Solid-state luminescence properties and thermo gravimetric analyses of these two compounds were investigated, respectively.

Synthesis, Crystal Structure and Antibacterial Activities of 3-[3-Methyl-(2-thienyl)methyl- enehydrazinocarbonyl]-(1H)-1,2,4-triazole

The title compound, C9H9N5OS, was synthesized by the reaction of 3-（1H）-1,2,4 -triazole hydrazine with 3-methyl-2-thiophenecarboxaldehyde in ethanol. The single crystal structure has been determined by X-ray diffraction analysis. The crystal belongs to monoclinic system, space group P2 1/n with a = 9.5550（10）, b = 11.9847（12）, c = 10.1074（11） A,β= 112.995（2）° V= 1065.47（19） A^3, Z = 4,μ = 0.290 mm^-1, Mr= 235.27, Dc = 1.467 g/cm^3 and F（000） = 488. The structure was solved by direct methods and refined to R = 0.0449. The crystal structure involves intermolecular hydrogen bonds of N-H…O and N-H…N as well as intramolecular hydrogen bond of N-H…N. Its biological activity has also been determined showing this type of compounds has certain antibacterial activity.

Synthesis and Crystal Structure of Picrates of 3,5-Diamino-1,2,4-triazole

The title compound C2N5H6＋C6N3O7H2-was synthesized by the reaction of 3,5-diamino-1,2,4-triazole and picric acid in the mixture of ethanol and water solution.Single crystals suitable for X-ray measurement were obtained at room temperature.The structure was characterized by elemental analysis and IR and determined by X-ray diffraction analysis.Crystallographic data：C8N8H8O7,Mr = 328.22,monoclinic,space group C2/c with a = 22.815（2）,b = 4.8086（5）,c = 22.564（2）,β = 93.976（2）°,V = 2469.6（4）3,Dc = 1.766 g/cm3,Z = 8,μ = 0.156 mm-1,F（000） = 1344,the final R= 0.0309,wR= 0.0864.

Synthesis and Crystal Structure of N′-(4-fluorobenzylidene)-2-(1H-1,2,4-triazole-1-yl)acetohydrazide

N′-（4-fluorobenzylidene）-2-（ 1H-1,2,4-triasole-1-yl） acetohydrazide was synthesized by the reaction of 4-flu- orobenzaldehyde with 2-（ 1H-1,2,4-triazole-1-yl） acetohydrazide. The structure was confirmed via elemental analysis, MS, ^1H NMR, IR, and X-ray diffraction. It crystallized in a monoclinic system with space group P2 （ 1 ）, α = 0.4905（1） nm, b =0. 8160（2） nm, c = 1.4105（3） nm, β =93. 33（3）°, Z=2, V=0.5636（2） nm^3, Do =1.457 Mg/m^3,μ =0. 112 mm^-1 , F（000） =256, and final R1 =0. 0685. Several intermolecular hydrogen-bond interactions existed in the crystal structure, facilitating the stabilization of the compound.

Synthesis, Crystal Structure and Biological Activity of 4-Amino-2,4-dihydro-5-((3,5-dimethyl-1H-pyrazol-1-yl)methyl)-3H-1,2,4-triazole-3-thione Schiff Base

The target compound 1,2,4-triazole Schiff base containing pyrazole ring was synthesized by 4-amino-2,4-dihydro-5-（（3,5-dimethyl- lH-pyrazol-1-yl）methyl）-3H-1,2,4-triazole-3-thione and 3,4,5-trimethoxy benzaldehyde.The structure was confirmed by IR,~1H NMR,H RMS,elemental analysis and single-crystal X-ray diffraction.The crystal belongs to the triclinic system,space group P1 with a = 7.8772（17）,b = 8.2986（18）,c = 15.392（3） A,α= 93.360（4）,β= 94.609（4）,γ= 93.584（4）°,C（18）H（22）N6O3S,Mr= 402.47,V= 998.9（4） A^3,Z= 2,F（000） = 422,Dc =1.335 g/cm^3,μ= 0.194 mm^（-1）,the final R = 0.0533 and wR = 0.1329 for 3517 observed reflections with I 2σ（I）.The preliminary bioassay results indicate that the target compound has good fungicidal activity against Gibberlla nicotiancola in EC50 value and F.O.f.sp.niveum in EC（95） value.

Synthesis and Crystal Structure Analysis of 4-Dibenzaldehydeamino-4H-1,2,4-triazole Diacetate

The new title compound 4-dibenzaldehydeamino-4H-1,2,4-triazole diacetate （C16H18N8O4,Mr = 386.38） has been prepared and its crystal structure was determined by single- crystal X-ray diffraction. The crystal is of monoclinic,space group P21/n with a = 8.1371（17）,b = 7.1237（12）,c = 16.325 （2）A,β = 100.366（2）°,V = 930.9（3） A^3,Z = 2,Dc = 1.378,F（000） = 404,μ = 0.104 mm^-1,MoKa radiation （λ = 0.71073 ）,R = 0.0307 and wR = 0.1196 for 4632 observed reflections with I 〉 2σ（I）. X-ray diffraction analysis reveals that the molecule is not flat and the crystal structure is stabilized mainly by van der Waals interactions.

Synthesis and Crystal Structure of Ag_2(admtrz)_2(CF_3CO_2)_2(admtrz=4-amino-3,5-dimethyl-1,2,4-triazole)

The title compound (Ag2F6O4N8C12H16, Mr = 666.07) was synthesized and its crystal structure was determined by single-crystal X-ray diffraction method. It crystallizes in orthorhombic, space group Fddd with cell parameters: a = 12.2718(1), b = 23.3229(1), c = 29.1918(1) ? V = 8355.10(8) 3, Z = 16, Dc = 2.118 g/cm3, F(000) = 5184 and m = 1.966 mm-1. The structure was solved by direct methods and refined by full-matrix least-squares methods. The final R = 0.0624 and Rw = 0.1699 for 1584 observed reflections with I ≥ 2.0s(I). The molecular structure consists of two trigonal silver atoms bridged by double triazole ligands. The distance between the two silver atoms Ag(1)…Ag(1A) is 3.475(2) ?

Solid Phase Synthesis of 3,4,5-Trisubstituted-1,2,4-Triazoles Derivatives from the Resin-Bound Acylhydrazines

An extension of our methodology on solid-phase synthesis of 3,4,5-trisubstituted-1,2,4-triazoles under mild conditions has been developed. Firstly, the resin-bound acylhydrazine is reacted with orthoesters to provide resin-bound 1,3,4-oxadiazoles. Secondly, condensation of 1,3,4-oxadiazoles resin with the corresponding arylamines hydrochloride to form the the resin-bound triazoles. 3,4,5-Trisubstituted-1,2,4-triazoles derivatives were obtained from resin-bound acylhydrazines in several steps providing 78% - 87% overall yields and excellent purity. The advantages of this method include straightforward operation and high yield and purity of the products.

Crystal Structure and Thermal Behavior of a Novel Cocrystal Consisting of 3,3’-Dinitrimino-5,5’-Bis(1H-1,2,4-triazole),H_(2)O and(CH3)_(2)SO

A typical nitroimine bistriazole（DNABT） was synthesized with high yield（90.4%） by nitration reaction from DABT in HNO3 and NH4NO3. Furthermore, a novel cocrystal（1） consisting of DNABT, H2O and DMSO in a 1：2：2 molar ratio was analysized on the crystal structure. Cocrystal 1 crystallizes in the triclinic system, space group P1 with a = 6.3124（18）, b = 8.233（2）, c = 9.775（3） A, β = 98.326（4）°, V = 481.59（74）A^3, Z = 2, Dc = 1.55 g/cm^3, F（000） = 234, μ = 0.337 mm^-1, S = 1.078, the final R = 0.0609 and w R = 0.2743. Additionally, the crystal structure is built up by four strong and seven weak hydrogen bonds. And the hydrogen bond network contributes to the stability of DNABT molecule. Typical TGA and DSC curves indicate the cocrystal 1 includes one endothermic and one exothermic decomposition processes, and the peak temperature at each process is 164.0 and 245.0 ℃. The nonisothermal decomposition kinetics analysis was performed by means of the Kissinger and Ozawa methods. The apparent activation energy（Ea） and pre-exponential factor（A） of the two decompositions are 96.0 kJ·mol^-1, 108.1 s^-1 and 215.8 kJ·mol^-1, 1018.9 s^-1, respectively.

Aromatic Multicarboxylate Ligands Tuned One-and Three-dimensional Zn(Ⅱ) Coordination Polymers Based on 3-(1H-pyrazol-4-yl)-5-(pyridin-3-yl)-1,2,4-triazole

Two aromatic multicarboxylate ligands tuned Zn(Ⅱ) coordination polymers, namely, {[Zn0.5(H2L)(tp)0.5(H2O)]H2O}n(1) and {[Zn2(HL)(btc)(H2O)]H2O}n(2)(H2L = 3-(1 Hpyrazol-4-yl)-5-(pyridin-3-yl)-1,2,4-triazole, H2tp = terephthalic acid;H3 btc = 1,3,5-benzenetricarboxylic) have been synthesized. Their structures were characterized by single-crystal X-ray diffraction analysis, elemental analyses and infrared spectra. Compound 1 possesses a one-dimensional chain structure and is finally extended into a three-dimensional supramolecular architecture though hydrogen bonding interactions. Compound 2 shows a three-dimensional framework. Meanwhile, compounds 1 and 2 exhibit luminescent emission in the solid, and can be investigated as potential luminescent materials.

Synthesis, Crystal Structure, Antibacterial Activities and Theoretical Computation of 3-(2-Hydroxybenzly)-4-(4-isopropylbenzyl- ideneamino)-(1H)-1,2,4-triazole-5-thione

The title compound C18H18N4OS has been synthesized by the reaction of 3-（2-hydroxy- benzyl）-4-amino-（1H）-1,2,4-triazole-5-thione with 4-isopropylbenzaldehyde in ethanol and characterized by IR, ^1H NMR spectra and elemental analysis. Its structure was determined by X-ray diffraction analysis. The crystal belongs to monoclinic, space group P21/c with a = 11.605（2）, b = 7.401（1）, c = 20.339（2） A, β= 103.05（2）°, V= 1701.8（4） A^3, Z = 4, Mr = 338.42,μ = 0.202 mm^-1, Dc = 1.321 g/cm^3 and F（000） = 712. The structure was solved by direct methods and refined to R = 0.0428 and wR = 0.1069. Due to the intramolecular O-H…N hydrogen bond and π-π stacking interactions between the benzene （C（1）～C（6）） and triazole rings, the two planes are essentially coplanar. Their biological activities have been measured, showing this type of compound has certain antibacterial activity for Staphylococous aureus and Bacillus subtilis. Based on the quantum chemistry calculation at the RHF/6-31G level, the frontier orbitals and electrostatic potential of the title compound were also discussed.

Structure and Biological Activities of 2-(1,3-Dithiolan-2-ylidene)-1-phenyl-2-(1,2,4-triazol-1-yl)ethanone

In order to find leading compounds with an excellent fungicidal activity, the title compound 2-（ 1,3-dithiolan-2- yl-idene）-1-phenyl-2-（ 1,2,4-tfiazol-1-yl） ethanone was synthesized according to the biological isosterism and its structure was confirmed by means of IR, MS, ^1 H NMR and elemental analysis. The single crystal structure of the title compound was determined by X-ray diffraction. The preliminary biological test shows that the synthesized compound exhibits some biological activities.

Studies on Acylthiosemicarbazides and Related Heterocycles(ⅪⅤ)——Synthesis and Bactericidal Activity of 1-(5-(3-Pyridyl)-2H-Tetrazol-2-ylacetyl) -4-Arylthiosemicarbazides and 3- (5- (3-Pyridyl)-2H-Tetrazol-2-ylmethyl)-4-Aryl-1,2 ,4-Triazole-5-Thiones

Introduction In the preceding paper it was described that various 1-acyl-4-substituted thiosemicarbazides and their derivatives exhibited a broad spectrum of antibacterial activities. Kothari pointed out that some heterocycles linked with tetrazole and 1,2,4-triazole can be used as antiinflammatory agent. We have also demonstrated that both 3-(5-a- naphthyl)-2H-tetrazol-2-ylmethyl)-4-aryl-1,2,4-triazole-5-thiones and 3-(3-pyridyl)-