Utilization of DmbNHNH2 in the synthesis of amino-substituted 4-((3,5-diamino-1H-pyrazol-4-yl)diazenyl)phenols

(2,4-Dimethoxybenzyl)hydrazine (DmbNHNH₂) was utilized in the synthesis of Dmb-protected 4-((3,5-diamino-1H-pyrazol-4-yl)diazenyl)phenols. This unambiguous protection of the pyrazole endocyclic nitrogen atom enabled the preparation of amino-substituted 4-((3,5-diamino-1H-pyrazol-4yl)diazenyl)phenols that were inaccessible through direct substitution. The Boc group could be selectively cleaved in the presence of the Dmb group.     

Three coordination polymers constructed from succinic acid and 1,4-bis(1H-imidazol-4-yl)benzene: synthesis,crystal structures,and properties

Three coordination polymers involving transition metals, namely [Co(suc)(1,4-bib)(H₂O)₂]_n (1), [Mn(suc)(1,4-bib)(H₂O)₂]_n (2), [Cd(suc)(1,4-bib)]_n (3) (H₂suc?=?succinic acid, 1,4-bib?=?1,4-bis(1H-imidazol-4-yl)benzene), have been synthesized under solvothermal conditions. All three compounds were characterized by single-crystal X-ray diffraction, elemental analysis, FTIR, UV–Vis spectroscopy, powder X-ray diffraction and thermogravimetric analyses. Compounds 1 and 2 show 2D metal–organic layers with the point symbol of {4⁴·6²}. The 3D framework of compound 3 displays a 4-connected dia net with the point symbol of {6⁶} topology. Magnetic susceptibility studies of compound 1 indicate weak antiferromagnetic coupling between the Co(II) centers. The adsorption experiment results show that compound 3 exhibits rapid and selective separation of congo red over methylene blue and rhodamine B.     

Spectral properties and binding study of DNA complexes with a rigid bisintercalator 1,4-bis((N-methylquinolinium-4-yl)vinyl)benzene

The DNA binding behavior of potentially bisintercalating ligand 1,4-bis((N-methyl quinolinium-4-yl)vinyl)benzene was studied by spectrophotometric titration, circular dichroism and matrix-assisted laser desorption-ionization-time-of-flight (MALDI-TOF) mass spectrometry. The formation of large DNA-ligand aggregates observed at low DNA concentration was ascribed to the interstrand cross-linking due to the bisintercalation and/or electrostatic interactions. On the other hand, a monointercalation was observed at higher DNA concentration and in the presence of higher content of NaCl. Intercalative DNA-ligand complex was featured by red shifted absorption band, modest hypochromicity and the presence of induced CD signal. MALDI-TOF mass spectra of short oligonucleotide-ligand systems revealed the formation of 1:1 complexes of the ligand with duplex and single-stranded oligonucleotides as well as a higher molecular weight species.     

Construction of two metal coordination polymers based on 1,4-terephthalate and 1,4-bis(1,2,4-triazol-1-ylmethyl)benzene

Two new metal-organic frameworks, namely, Cd(BDC)(Btx) · 0.25(H₂O) (I) and Co₃(BDC)₃(Btx)₄(H₂O)₄ (II) (H₂BDC = 1,4-terephthalate acid and Btx = 1,4-bis(1,2,4-triazol-1-ylmethyl)benzene), have been synthesized under hydrothermal conditions and characterized by elemental analysis, IR, TGA, and single crystal X-ray diffraction. Complex I exhibits a scarcely reported an eight-connected (4²⁴.6⁴) net with dinuclear cadmium clusters as secondary building units, whereas complex II displays a three-dimensional co-ordination polymer with a rare (4,6)-connected net described by the (4⁴.6²)₂(4⁸.6⁷) Schläfli symbol. In addition, the luminescence measurements reveal that complex I exhibits strong fluorescent emissions in the solid state at room temperature.     

High dimensional coordination polymers based on transition metals, 1,2,4,5-benzenetetracarboxylate anion and 1,3-bis(4-pyridyl)propane nitrogen ligand

The reaction between 1,2,4,5-benzenetetracarboxylic acid (H₄BT) and transition metal ions Mn⁺², Co⁺² and Cu⁺² in the presence of the N-donor co-ligand 1,3-bis(4-pyridyl) propane (BPP) has afforded three new coordination polymers named, {[Mn₄(BT)₂(BPP)₆(H₂O)₆]·4H₂O}_nMnBTBPP, {[Co₂(BT)(BPP)₂(H₂O)₆]·2H₂O}_nCoBTBPP and {[Cu₂(BT)(BPP)₂(H₂O)]·6H₂O}_nCuBTBPP. They were characterized by a combination of analytical, spectroscopic and crystallographic methods. According to the thermal analysis results all the compounds present coordinated and lattice water molecules in the structures. In compounds MnBTBPP and CoBTBPP, the metal centers exhibit octahedral geometry while in compound CuBTBPP, the Cu⁺² ions adopt square-planar and square-pyramidal geometries. In all cases, both BPP and BT ligands are coordinated to the metal sites in the bridging mode extending the polymeric networks. The BT ligand carboxylate groups act in a monodentate coordination mode as indicated by the Raman spectra data through the Δν [ν_asym(COO) − ν_sym(COO)] value.     

Syntheses and structures of three new coordination polymers with the flexible 1,2-bis(1,2,4-triazol-1-yl)ethane ligand

Three new coordination polymers {[Ni(bte)₂(NCO)₂](H₂O)} _n (1), {[Ni(bte)₂(N₃)₂](H₂O)} _n (2) and {[Ag(bte)₂](NO₃)} _n (3) (bte?=?1,2-bis(1,2,4-triazol-1-yl)ethane) were synthesized and characterized by X-ray crystallography, IR and thermogravimetric analysis. The coordination geometry of the Ni(II) atom is distorted octahedral, coordinated equatorially by four nitrogen atoms from four triazole rings of four symmetry-related bte ligands, and axially by two nitrogen atoms from two isocyanate anions in 1 and azide anions in 2, respectively. The structures of 1 and 2 are both polymeric, with 18-membered spiro-fused rings and each 18-membered ring involving two inversion-related bte molecules. The coordination geometry of the Ag(I) atom in 3 is distorted tetrahedral, formed by four nitrogen atoms from four triazole rings of four symmetry-related bte ligands. Each bte ligand links two Ag(I) atoms and forms a two-dimensional undulated (4,4) network in 3.     

Two coordination polymers based on mixed 1,4-bis(benzimidazo-1-yl)benzene and O-donor linker ligands: syntheses,crystal structures and properties

Transition Metal Chemistry - Two coordination polymers based on 1,4-bis(benzimidazo-1-ly)benzene (L) and O-donor linking co-ligands, namely {[ZnL(mipa)(H2O)]}n (1) and {[Cd2L2(sdba)Cl2]}n (2)...     

[4+2]-Cycloaddition of 3,6-bis(3,5-dimethyl-4-R-pyrazol-1-yl)-1,2,4,5-tetrazines with alkenes

A number of 1,4-dihydropyridazines and pyridazines were prepared by the Diels-Alder reaction with an inverse electron demand from cyclic heterodiene systems, 3,6-bis(3,5-dimethyl-4-R-pyrazol-1-yl)-1,2,4,5-tetrazines, and some enamines as well as from 4-vinylpyridine, butyl vinyl ether, phenylacetylene, and acrylamide. The reaction of 3,6-bis(3,5-dimethylpyrazol-1-yl)-1,2,4,5-tetrazine with styrene afforded 4,5-dihydropyridazine, which was readily oxidized by atmospheric oxygen to form the corresponding pyridazine. Electron-withdrawing substituents (Br or Cl) in the pyrazole rings accelerate [4+2]-cycloaddition. When heated, 1,4-dihydropyridazines, which were synthesized from tetrazines and enamines, eliminated amine to give pyridazines. The reactivities of tetrazines were evaluated by quantum-chemical methods. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 2, pp. 354–360, February, 2000.     

Syntheses and structures of three new coordination polymers with the flexible 1,4- bis (imidazol-1-yl)butane ligand

Three new coordination polymers [Co(bimb)₂(NCS)₂] _n (1), {[Co(bimb)₂(dca)₂]?·?CH₃CN} _n (2) and [Cu(bimb)₂(NO₃)₂] _n (3) (bimb?=?1,4-bis(imidazol-1-yl)butane, dca?=?dicyanamide) were synthesized and characterized. In 1, each Co(II) links two Co(II)'s by double bimb ligands and extends to form a one-dimensional chain containing the Co₂(bimb)₂ 22-membered metallocycle. 2 and 3 are two-dimensional (4, 4) networks linked by bimb bridges. The conformations of the bimb ligands in 1, 2 and 3 are analyzed.     

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)N_6O_3S,M_r= 402.47,V= 998.9(4) A~3,Z= 2,F(000) = 422,D_c =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,crystal structure and fungicidal activity of 1-(4-chlorophenyl)-2-(5-((3,5-dimethyl-1H-pyrazol-1-yl)methyl)-4-phenyl-4H-1,2,4-triazol-3-ylthio)ethanone

A novel bis-heterocyclic compound was synthesized and characterized. The crystal structure of the title compound (C₂₂H₂₀ClN₅OS, Mr = 437.94) has been determined by single-crystal X-ray diffraction. The crystal is of triclinic, space group P-1 with a = 8.646 (2), b = 9.148 (3), c = 14.540 (4) Å, α = 94.422 (4), β = 98.500 (4), γ = 102.823 (4)°, V = 1101.8 (5) Å³, Z = 2, F(000) = 312, Dc = 1.320 g/cm³, μ = 0.2900 mm^?1, the final R ₁ = 0.041000 and wR ₂ = 0.1160 for 2675 observed reflections with I > 2σ(I). A total of 5623 reflections were collected, of which 3866 were independent (R _int = 0.019000). The fungicidal activity of title compound was determined, the results showed the title compound displayed moderate fungicidal activity against G. zeae Petch, Phytophthora infestans (Mont.) de Bary, Botryosphaeria berengeriana f. sp. piricola (Nose) koganezawa et Sakuma, Fusarium oxysporum f.sp. cucumerinum, and Cercospora arachidicola.     

Novel coordination polymers with 1,4-di(benzimidazole-1-yl)benzene modulated by an anion: Syntheses, structures and properties

Three novel coordination polymers, {[Co(L)(SO₄)(H₂O)](CH₃OH)}_∞ (1), {[Cd(L)₂(SiF₆)](H₂O)}_∞ (2) and [Zn(L)(NO₃)₂]_∞ (3), synthesized from 1,4-di(benzimidazole-1-yl)benzene (L), have been characterized by infrared spectroscopy, elemental analysis and single crystal X-ray diffraction. Compounds 1–3 exhibit different structures. Complex 1 has a 3-D diamond network containing 1-D Co^II chains connected by SO ₄ ^2? · anions; 2 has a 3-D-Po framework with 1-D porous channels along the c axis; and 3 has a 1-D zig-zag chain structure with a 2-D supramolecular network based on π-π interactions. The magnetic properties of 1 and the solid state fluorescence spectra of 2 and 3 have also been explored.     

Synthesis,Dimeric Crystal Structure,and Fungicidal Activity of 1-(4-Methylphenyl)-2-(5-((3,5-dimethyl-1H-pyrazol-1-yl)methyl)-4-phenyl-4H-1,2,4-triazol-3-ylthio)ethanone

Abstract

A new triazole compound, C₄₆H₄₆N₁₀O₂S₂, has been synthesized, and the crystal structure was determined by a single crystal X-ray diffraction study. The fungicidal activity of the title compound was determined, and the results showed that it displays moderate fungicidal activity.

Supplemental materials are available for this article. Go to the publisher's online edition of Phosphorus, Sulfur, and Silicon and the Related Elements to view the free supplemental file.

GRAPHICAL ABSTRACT      

1-芳基亚甲基-2-(6-(3,5-二甲基-1H-吡唑-1-基)-1,2,4,5-四嗪-3-基)肼的合成及抗菌活性

以水合肼和硝酸胍为原料,经过环合、氧化和肼化,得到3-(3,5-二甲基-1H-吡唑-1-基)-6-肼基-1,2,4,5-四嗪(4),以此为原料和不同芳香醛发生腙化反应,得到系列1-芳基亚甲基-2-(6-(3,5-二甲基-1H-吡唑-1-基)-1,2,4,5-四嗪-3-基)肼(5),产物经元素分析、1H NMR、IR和MS表征。所合成的系列化合物抗菌活性测试表明,它们对大肠杆菌、金黄色葡萄球菌、枯草杆菌等3种细菌表现出一定程度的抑制活性。     

Synthesis and isomerism of 2-(3,5-diaryl-1H-pyrazol-4-yl)-1H-benzimidazoles

2-(3,5-Diaryl-1H-pyrazol-4-yl)-1H-benzimidazoles have been obtained by the cyclocondensation of 2-phenacyl-1H-benzimidazoles with 4-nitro- and 4-methoxybenzoylhydrazines. The reaction mechanism and the isomerism of the obtained products are discussed. According to the data of ¹H NMR spectroscopy the stabilized isomer is that in which the electron-withdrawing aryl substituent is located in position 3 and the electron-donating substituent in position 5 of the pyrazole ring.     

Cu(II) complexes with 4,6-bis(3,5-dimethyl-1 H -pyrazole-1-yl)pyrimidine, 4-(3,5-dimethyl-1 H -pyrazole-1-yl)-6-(3,5-diphenyl-1 H -pyrazole-1-yl)pyrimidine: Synthesis and catalytic activity in ethylene polymerization reaction

The Cu(II) complexes with 4,6-bis(3,5-dimethyl-1H-pyrazole-1-yl)pyrimidine (L¹) and 4-(3,5-dimethyl-1H-pyrazole-1-yl)-6-(3,5-diphenyl-1H-pyrazole-1-yl)pyrimidine (L²) of the composition Cu₂L¹Br₄ and Cu₂L²A₄ (A = Cl, Br), respectively, were synthesized and studied by IR and magnetochemical methods. The molecular structure of the complexes is likely to be binuclear. In the presence of cocatalysts methylaluminoxane and triisobutylaluminium, the title complexes exhibit catalytic activity in the ethylene polymerization reaction. Original Russian Text ? M.B. Bushuev, V.P. Krivopalov, N.V. Semikolenova, Yu.G. Shvedenkov, L.A. Sheludyakova, G.G. Moskalenko, L.G. Lavrenova, V. A. Zakharov, S.V. Larionov, 2007, published in Koordinatsionnaya Khimiya, 2007, Vol. 33, No. 8, pp. 612–617.     

Syntheses and characterizations of five coordination polymers constructed by 3,5-bis(pyridin-3-ylmethoxy)benzoic acid ligand

Five coordination polymers, namely [Cd(L3)₂]·H₂O (1), [Zn(L3)₂] (2), [Co(L3)₂] (3), [Ni(L3)₂] (4) and [Cu₂(L3)₂]·3H₂O (5), where L3 = 3,5-bis(pyridin-3-ylmethoxy)benzoic acid, have been synthesized under hydrothermal conditions. Their structures have been determined by single-crystal X-ray diffraction analyses and further characterized by elemental analyses, IR spectra, and thermogravimetric (TG) analyses. Compound 1 is a binodal (3,4)-connected net with (6³)(6⁶) topology. Compounds 2–4 are isostructural and described by the uninodal (4,4)-connected net with (4⁴ · 6²) Schläfli symbol. The structure of 5 is a 2D binodal (6,3) net. In addition, the luminescent properties of compounds 1 and 2 have been studied in the solid state at room temperature.     

Electron ionization mass spectrometric study of 1,4-dihydro-4-substituted 2,6-dimethyl-3,5-bis(alkoxycarbonyl)pyridines

Using the accurate masses obtained from a time-of-flight instrument and the tandem mass spectrometric (MS/MS) data from an ion trap instrument, electron ionization mass spectra of a series of 1,4-dihydro-4-substituted 2,6-dimethyl-3,5-bis(alkoxycarbonyl)pyridines are reported and rationalized. Two sets of fragmentation pathways are proposed. One involves the formation of fragment ions containing the 1,4-dihydropyridine structure, and the other of ions containing a pyridine ring.