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1.
Guan-Ping Yu Wen-Zhao Bi Guo-Dong Si Ya-Xun Yang Haji Akber Aisa Liang-Zhong Xu 《Structural chemistry》2009,20(4):569-576
A series of 1-[(1,3,4-thiadiazol-2-yl)methyl]-1H-1,2,4-triazole derivatives were prepared and evaluated for their antifungal
activities. The chemical structures of these compounds were determined by means of elemental analyses, 1H NMR, and X-ray crystallography. Quantitative structure–activity relationship (QSAR) studies were performed on these compounds
using physicochemical parameters as independent parameters and antifungal activity as a dependent parameter, where antifungal
activity correlated best (r > 0.9) with hydrophobic parameters (π) and indicator (H). Moreover, the results are interpreted on the basis of a multiple regression model. The model has been internally and externally
validated. Furthermore, the domain of applicability which indicates the area of reliable predictions is defined. 相似文献
2.
Abstract
Based on the polydentate ligand 3,5-bis(3-pyridyl)-1H-1,2,4-triazole (3,3′-Hbpt), three coordination compounds [Zn(3,3′-Hbpt)(ip)]·2H2O (1), [Zn(3,3′-Hbpt)(5-NO2-ip)]·H2O (2), and [Zn(3,3′-Hbpt)2(H2pm)(H2O)2]·2H2O (3) have been hydrothermally constructed with H2ip, 5-NO2-H2ip and H4pm as auxiliary ligands (H2ip = isophthalic acid, 5-NO2-H2ip = 5-NO2-isophthalic acid, H4pm = pyromellitic acid). Structural analysis reveals that Zn(II) ions serve as four-coordinated, five-coordinated, and six-coordinated connectors in 1–3, respectively, while 3,3′-Hbpt adopts μ-Npy and Npy coordination modes in two typical conformations in these target coordination compounds. Dependently the applied ligand, compounds 1–3 exhibit either 1D channel, cage or chain structures, respectively. In addition, the luminescence properties of 1–3 have been investigated in the solid state at room temperature. 相似文献3.
Rambabu Sirgamalla Ashok Kommakula Sonyanaik Banoth Ravi Dharavath Kurumanna Adem Madhu Palithepu 《合成通讯》2018,48(8):954-962
A new series of 1,8-bis(4-((5-phenyl-1,3,4-oxadiazol-2-yl) methoxy)-substituted aryl) naphthalene-1,8-dicarboxamide derivatives (6a–j) were synthesized in the presence of POCl3 and obtained good yields. All the synthesized novel compounds were characterized by IR, 1H NMR, 13C NMR, HRMS spectroscopic data and elemental analysis. All the synthesized compounds evaluated for their antibacterial and antifungal activities. The antibacterial activity screened against Gram-positive bacteria Staphylococcus aureus and Gram-negative bacteria Escherichia coli and used standard reference drug ciprofloxacin. The antifungal activity screened against two pathogenic fungal strains Aspergillus niger and Candida albicans used a reference standard drug Voriconazole. All these compounds (6a–j) demonstrate good antibacterial and antifungal activity. Among them, compounds 6h and 6c show highest antibacterial and antifungal activity. 相似文献
4.
Four compounds have been synthesized and characterized by1H NMR spectroscopy and elemental analyses, among which 1-(4,5-dihydro-3-phenyl-pyrazol-1-yl)-2-(1H-1,2,4-triazol-1-yl)ethanone 3a was further confirmed by X-ray crystallographic analysis. The biological activities of these compounds were tested, with the result that they displayed moderate fungicidal activities. In addition, a MO calculations using density functional theory (DFT) at B3LYP/6-31G* level have also been carried out, and the structure–activity relationships for these compounds are discussed. 相似文献
5.
The conformational behavior of 1,2-difluoroethane (1), 1,2-dichloroethane (2), 1,2-dibromoethane (3), and 1,2-diiodoethane (4) have been analyzed by means of complete basis set CBS-QB3, hybrid-density functional theory (B3LYP/Def2-TZVPP) based methods
and natural bond orbital (NBO) interpretation. Both methods showed the expected greater stability of the gauche conformation
of compound 1 compared to its anti conformation. Contrary to compound 1, the anti conformations of compounds 2–4 are more stable than their gauche conformation. The stability of the anti conformation compared to the gauche conformation
increases from compound 1 to compound 4. The NBO analysis of donor–acceptor (σ → σ*) interactions showed that the generalized anomeric effect (GAE) is in favor of
the gauche conformation of compound 1. Contrary to compound 1, GAE is in favor of the anti conformations of compounds 2–4. The GAE values calculated (i.e., GAEanti − GAEgauche) increase from compound 1 to compound 4. On the other hand, the calculated dipole moment values for the gauche conformations decrease from compound 1 to compound 4. In the conflict between the GAE and dipole moments, the former succeeded in accounting for the increase of the anti conformation
stability from compound 1 to compound 4. There is a direct correlation between the calculated GAE, ∆[r
c–c(G) − r
c–c(A)] and ∆[r
c–x(A) − r
c–x(G)] parameters. The correlations between the GAE, bond orders, total steric exchange energies (TSEEs), ΔG
Anti–Gauche, ΔG
‡(Gauche → Gauche′, C
2v), ΔG
‡(Anti → Gauche, C
2), dipole–dipole interactions, structural parameters, and conformational behaviors of compounds 1–4 have been investigated. 相似文献
6.
Christina Zalaru Mino R. Caira Florea Dumitrascu Constantin Draghici Elena Cristea 《Structural chemistry》2009,20(3):377-385
Five new pyrazole acetanilides were synthesized by N-alkylation of pyrazole and its derivatives with 4′-propionyl-2-iodoacetanilide. Compounds 1–5 were characterized by 1H NMR, 13C NMR, IR, UV–Vis, MS, and elemental analysis. X-ray structures of representative compounds 1, 3, and 5 established their conformations and solid-state hydrogen bonding preferences. Acute toxicity, local anesthetic, and antiarrhythmic
activities were assessed for compounds 1–5 using established protocols. Lower potencies and lower acute toxicities were recorded relative to lidocaine. Enhanced anesthetic
activity of compound 3 was attributed to the presence of the propionyl group in the molecule.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
7.
Rodrigo A. de Souza Antonio E. Mauro Adelino V. G. Netto Gislaine A. da Cunha Eduardo T. de Almeida 《Journal of Thermal Analysis and Calorimetry》2011,106(2):375-378
Palladium(II) coordination compounds of general formula trans-[PdX2(isn)2], X = Cl− (1), N3
− (2), SCN− (3), NCO− (4), isn = isonicotinamide; were synthesized and characterized in solid state by elemental analysis, infrared spectroscopy,
and simultaneous TG–DTA. TG experiments reveal that the compounds 1–4 undergo thermal decomposition in three or four stages, yielding Pd0 as final residue, according to calculus and identification by X-ray powder diffraction. 相似文献
8.
Sumitava Khan Subhasis Roy Kishalay Bhar Partha Mitra Alexandra M. Z. Slawin Barindra Kumar Ghosh 《Transition Metal Chemistry》2011,36(1):99-106
Two hexacoordinated mononuclear Co(III) compounds of the type cis-[Co(L)(N3)2] X [1, X = ClO4; 2, X = PF6; L = N,N′-(bis(pyridine-2-yl)benzylidine)-1,4-butanediamine] have been synthesized and characterized by physicochemical and spectroscopic
methods. The crystal structures of complexes 1 and 2 both have distorted octahedral geometry with two terminal azides in mutual cis orientations. In the crystalline state, two
mononuclear units of 1 are associated by weak C–H…π interactions to produce a dimeric unit, which packs through C–H…O hydrogen bonds and π…π interactions
leading to a 2-D continuum. The mononuclear units in 2 are engaged in weak cooperative intermolecular C–H…π interactions and multiple C–H…F hydrogen bonds giving rise to a 3-D
network structure. These diamagnetic compounds are redox active and show luminescence in DMF solutions. 相似文献
9.
Liviu V. Costea Vasile N. Bercean Valentin Badea Klaus Gerdes Ulrich Jordis 《Monatshefte für Chemie / Chemical Monthly》2006,137(6):737-744
Summary. 1H-3-Methyl-4-ethoxycarbonyl-5-(benzylidenehydrazino)pyrazoles are key intermediates in obtaining various heterocyclic systems
including pyrazolotriazoles. We present the voltammetric behavior of these compounds in nonaqueous media, with the following
para substituents grafted on the benzene ring: –N(CH3)2, –OH, –OCH3, –F, –Cl, –CF3, –NO2, as well as of the novel compounds with –Br, –I, and –SCH3 in the para position, in order to elucidate the influence of the various substituents on the mechanism of anodic oxidation. 相似文献
10.
Ji-Bo Liu Hao-Hong Li Zhi-Rong Chen Jun-Bo Li Xiao-Bo Chen Chang-Cang Huang 《Journal of Cluster Science》2009,20(3):515-523
Abstract A 1-D hybrid copper(I) halides, [(phen)Cu3I3]
n
(phen = 1,10-phenanthroline)(1) with novel D6R (double six-membered rings) Cu6I6 cores, was synthesized by solvothermal reaction and characterized by single-crystal X-ray diffraction. In 1, nitrogen atoms from phen replace two I of CuI4 tetrahedron to give distorted tetrahedral geometries (CuI2N2), then CuI2N2 tetrahedron shares corners via μ3-I to generate an extended 1-D zigzag chain. Two zigzag chains combines with one 1-D (Cu4I4)
n
chain containing D6R cores via μ3-I-Cu (from cores) bonds to form the infinite 1-D ribbonlike polymer along the a-axis. Furthermore, the title compound is stabilized by conspicuous C–H···I hydrogen bonds, π–π and d10–d10 metallic interactions. Experimental and theoretical optical property investigation indicates that 1 possesses semiconductor property. DFT calculation was executed to probe the electronic structure of 1. To our interest, phen act as a property control species with its π* electrons appear in the forbidden band.
Graphical Abstract A hybrid copper(I) halides [(phen)Cu3I3]
n
containing D6R cores was structurally determined, which was stabilized by conspicuous C–H···I hydrogen bonds, π–π and d10–d10 metallic interactions and possesses semiconductor property. DFT calculation indicate phen act as a property control species
with its π* electrons appear in the forbidden band.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
11.
Soraia Meghdadi Mehdi Amirnasr Mohammad H. Habibi Ahmad Amiri Fatemeh Ahmadi Keiko Kihara Takayoshi Suzuki Hamid Reza Bijanzadeh 《Transition Metal Chemistry》2008,33(7):879-886
The structure, spectroscopic, and electrochemical properties of [Co{(BA)2pn}(L)2]ClO4 complexes, where (BA)2pn = N,N′-bis(benzoylacetone)-1,3-propylenediimine dianion and the two ancillary ligands (L) are pyridine, py (1), and 4-methylpyridine, 4-Mepy (2), have been investigated. These complexes have been characterized by elemental analyses, IR, UV–Vis and 1H-NMR spectroscopy. The crystal structure of [Co{(BA)2pn}(py)2]ClO4 (1) has been determined by X-ray diffraction. The coordination geometry around cobalt(III) is best described as a distorted
octahedron. The electrochemical reduction of these complexes at a glassy carbon electrode in acetonitrile solution indicates
that the first reduction process corresponding to CoIII–CoII is electrochemically irreversible, which is accompanied by the dissociation of the axial N(py)–cobalt bonds. This process
becomes quasi-reversible upon the addition of excess py ligands. The second reduction step of CoII/I shows reversible behavior and is not influenced by the nature of the axial ligands.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
12.
Ming-Li Liu Jian-Min Dou Da-Cheng Li Da-Qi Wang Jian-Zhong Cui 《Transition Metal Chemistry》2012,37(1):117-124
The thiosemicarbazide and hydrazide Cu(II) complexes, [Cu3L21(py)4Cl2] (1), [Cu(HL2)py] (2) and [Cu(HL3)py] (3), (H2L1 = 1-picolinoylthiosemicarbazide, H3L2 = N′-(2-hydroxybenzylidene)-3-hydroxy-2-naphthohydrazide, H3L3 = 2-hydroxy-N′-((2-hydroxy-naphthalen-1-yl)methylene)benzohydrazide) have been prepared and characterized through physicochemical and spectroscopic
methods as well as X-ray crystallography. Complex 1 has a centrosymmetric structure with –N–N– bridged Cu3 skeleton. Neighboring molecules are linked into a 3D supermolecular framework by π–π stacking interactions, N–H···Cl and
C–H···Cl hydrogen bonds. Complexes 2 and 3 have similar planar structures but different dimers formed by concomitant Cu···N and Cu···O interactions, respectively. Solvent
accessible voids with a volume of 391 ?3 are included in the structure of complex 2, indicating that this complex is a potential host candidate. Thermogravimetric analysis shows that the three complexes are
stable up to 100 °C. 相似文献
13.
M. N. Khimich F. E. Gostev I. V. Shelaev O. M. Sarkisov E. A. Birgen B. M. Bolotin B. M. Uzhinov 《High Energy Chemistry》2010,44(6):482-491
Femtosecond dynamics of processes in the excited state of 2-(2-aminophenyl)-4H-3,1-benzoxazin-4-ones has been studied by femtosecond
absorption spectroscopy. The rate constants of intramolecular photoinduced proton transfer (IPPT) have been determined for
the N-substituted derivatives (0.7–11 ps−1). The IPPT rate constant depends on the inductive constant of the substituent and the potential barrier height, which was
calculated by a quantum-chemical method (TDDFT). The multiexponential character of the kinetics of photoinduced absorption
by the compounds with a low inductive constant of the N-substituent in the spectral region of the S1 → SN absorption and the stimulated emission of the IPPT product is explained by the rapid (∼10 ps−1) relaxation process preceding the IPPT. 相似文献
14.
Zhuo Wang Yong Heng Xing Chun Guang Wang Xiao Qing Zeng Mao Fa Ge Shu Yun Niu 《Transition Metal Chemistry》2009,34(6):655-661
A series of lanthanide–transition metal (Ln–M) complexes, namely, {[Ln2Cu(pydc)4(H2O)3]·H2O}
n
(Ln = Tb, Eu, Sm or Gd) (H2pydc = 2,5-pyridinedicarboxylic acid) have been synthesized hydrothermally by self-assembly of the lanthanide ions, copper(II)
ions and 2,5-pyridinedicarboxylic acid. All the complexes were characterized by physicochemical and spectroscopic methods;
in addition, structural analyses revealed that all four complexes crystallized in monoclinic space group P21
/c. The molecular structure contains both Cu and Ln atoms, with pydc ligands bridging the four coordinate Cu(II) centers and
eight coordinate lanthanide centers to form a 3-D net structure. Hence, copper is oxidized from Cu(I) to Cu(II) during the
preparation. In addition, the thermogravimetric analysis of 1 is discussed. Contrary to expectations, compounds 1–3 show no photoluminescent properties.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
15.
Dong-Yu Lv Zhu-Qing Gao Jin-Zhong Gu Jian-Zhao Liu Wei Dou 《Transition Metal Chemistry》2011,36(3):275-281
Two Mn(II) coordination polymers, namely [Mn(bpda)]
n
(1) and [Mn(bpda)(bpy)0.5]
n
(2) (H2bpda = 1,1′-biphenyl-3,3′-dicarboxylic acid and bpy = 4,4′-bipyridine), have been synthesized from H2bpdc, bpy, and MnSO4·2H2O under hydrothermal conditions. The complexes were characterized by physicochemical and spectroscopic methods, as well as
by X-ray crystallography. Compound 1 possesses a 3D structure consisting of carboxylate-bridged edge-sharing Mn–O–Mn double chains. Compound 2 features a 3D open structure with a dinuclear Mn(II) secondary building unit. Magnetic susceptibility measurements of compounds
1 and 2 exhibit antiferromagnetic interactions between the nearest Mn(II), with J = –11.3 cm−1 and g = 2.12 for 1, and J = –13.5 cm−1 and g = 2.12 for 2. 相似文献
16.
Udai P. Singh Vaibhave Aggarwal Sujata Kashyap Shailesh Upreti 《Transition Metal Chemistry》2009,34(5):513-520
[TpPh,MeNi(Cl)PzPh,MeH] (1) has been synthesized by the reaction of hydrotris(3-phenyl-5-methyl-pyrazol-1-yl) borate [TpPh,Me], NiCl2 · 6H2O and 3-phenyl-5-methyl-pyrazole [PzPh,MeH]. The reaction of 1 with variously substituted sodium p–X–benzoates resulted in the formation of complexes of the type [TpPh,MeNi(p–X–OBz)PzPh,MeH] (X = H for 2, F for 3, Cl for 4, NO2 for 5, Me for 6, OMe for 7, OH for 8, CHO for 9 and CN for 10). Single crystal X-ray studies suggest that all these complexes have a five-coordinate metal center and the benzoate groups
are monodentate in a square pyramidal geometry. The X-ray studies also reveal that the uncoordinated oxygen atom of the benzoate
forms intramolecular hydrogen-bonds with the NH group of the coordinated pyrazole. The substituents present on the benzoate
ring are involved in different types of intermolecular interactions and the complexes exhibit different crystal packing. Complexes
2–10 were tested for superoxide dismutase activity.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
17.
Habibe Tezcan Hülya ?en?z Nesrin Tokay 《Monatshefte für Chemie / Chemical Monthly》2012,287(11):579-588
Abstract
1-[(NO2, COOH)-substituted phenyl]-3,5-diphenylformazans were synthesized. The compounds were characterized by infrared (IR), ultraviolet–visible (UV–vis), 1H nuclear magnetic resonance (NMR), 13C NMR spectra, elemental analysis, and cyclic voltammetry. From the UV–vis spectra of substituted formazans it was seen that λ max values were shorter than the λ max value of unsubstituted formazan. It was observed that the shift values were dependent on the type and position of the substituents. A correlation between Hammett substituent coefficients and λ max values was obtained. The oxidation peak potentials of substituted formazans were found more anodic than that of unsubstituted formazan. The oxidation mechanism was a single step for the NO2-substituted formazans, and two steps for COOH-substituted formazans. 相似文献18.
Jian-Yong Zhang Yan-Qin Wang Hui-Qi Peng Ai-Ling Cheng En-Qing Gao 《Structural chemistry》2008,19(3):535-539
A new coordination polymer with interesting supramolecular architecture, [Zn(4-tzbz)]
n
(1) (4-tzbz = 4-(tetrazol-5-yl)benzoate), has been synthesized and characterized structurally. In this compound, the zinc(II)
ions are connected by the tetrazole ring in the μ2-1,4 bridging mode and the carboxylate group in the μ2-1,3 syn-anti bridging mode to generate 2D (4,4) sheets, and the adjacent sheets are linked further by the benzene rings to give the 3D
metal–organic framework with a 3,4-connected (83)(84122) topology. This compound in the solid state exhibits photoluminescence assignable to intraligand transitions, and, in particular,
the emission at 400 nm is significantly intensified due to the coordination of the ligand to Zn. 相似文献
19.
A new series of 1-((1-(1H-benzo[d]imidazol-2-yl)ethylidene)amino)-6-((arylidene)amino)-2-oxo-4-phenyl-1,2-dihydropyridine-3,5-dicarbonitriles (4a–o) have been synthesized for the development of antimicrobial agents. Newly synthesized compounds were evaluated for their in vitro antibacterial activity against Gram-positive bacteria (Pseudomonas aeruginosa, Streptococcus pyogenes), Gram-negative bacteria (Escherichia coli, Staphylococcus aureus), and antifungal activity (Candida albicans, Aspergillus niger, Aspergillus clavatus). These compounds were characterized by infrared, 1H NMR, 13C NMR, and mass spectra. The synthesized compounds 4b, 4e, 4 h, and 4k showed potent antimicrobial activity against tested microorganisms. 相似文献
20.
Two-dimensional complexes of [Cd(cpoa)(o-pbim)]
n
(1) and {[Cd3(cpoa)3(o-pbim)2] · 2H2O}
n
(2) (cpoa2− = 4-carboxyphenoxy acetate, o-pbim = 2-(2-pyridyl)benzimidazole) are synthesized under hydrothermal condition. Single crystal
X-ray diffraction analysis shows that complex 1 contains a mono-nuclear unit, whereas complex 2 contains a trinuclear unit. The structural difference of 1 and 2 can be attributed to the various coordination modes of asymmetrically semi-flexible cpoa2− ligand. The luminescent properties of these two compounds are also investigated. 相似文献