An X-ray and DFT Computational Study on 1-（Naphthalene-2-yl）-2-（1H-pyrazol-1-yl） ethanone O-butyl Oxime

The title compound, 1-(naphthalene-2-yl)-2-(1H-pyrazol-1-yl)ethanone O-butyl oxime, I, was synthesized. The crystal and molecular structures of I were determined by IR, 1H-NMR, mass spectrum, elemental analysis and X-ray single crystal diffraction. Molecular geometry from X-ray experiment of I in the ground state was compared using the Density Functional Theory (DFT) with B3LYP/6-311G(d,p) basis set. In addition, DFT calculation, molecular electrostatic potentials (MEP) and frontier molecular orbitals of I were performed at the B3LYP/6-311G(d,p) level of the theory.     

Synthesis, Crystal Structure and Bioactivities of 1-（4-Chlorophenyl）-3- [ 5-（pyrid-4-yl）- 1,3,4-thiadiazol-2-yl] urea

The title compound 1-(4-chlorophenyl)-3-[5-(pyrid-4-yl)-1,3,4-thiadiazol-2-yl]urea (C14H10ClN5OS, Mr = 331.79) has been synthesized by the reaction of 2-amino-5-(pyrid-4-yl)- 1,3,4-thiadiazole with 4-chlorobenzoyl azide, and its crystal structure was determined by single-crystal X-ray diffraction. The crystal belongs to triclinic system, space group P with a = 5.8550(8), b = 7.5668(10), c = 16.416(2) , α = 78.364(2), β = 81.204(2), γ = 84.749(2)°, V = 702.58(16) 3, Z = 2, Dc = 1.568 g/cm3, μ = 0.429 mm-1, F(000) = 340, the final R = 0.0442 and wR = 0.1092 for 2001 observed reflections (I > 2σ(I)). X-ray diffraction analysis reveals that the title molecule is nearly planar. In the crystal structure, the molecules are linked by strong intermolecular N-H…N hydrogen bonds together with weak nonclassical intermolecular (C-H…Y, Y = N, O and Cl) hydrogen bonds and stacked through π-π interactions. The preliminary bioassay shows that the title compound exhibits good fungicidal activities against Rhizoctonia solani, Botrytis cinerea and Dothiorella gregaria.     

Synthesis and crystal structures of three new complexes derived from 3-(pyridin-3′-yl)-5-(pyridin-2′′-yl)-1,2,4-triazole

Three new coordination complexes, [Cd₂(ppt)₂(cpba)]?·?(H₂O)₂ (1), [Zn(ppt)₂]?·?(H₂O) (2), and [Zn(MoO₄)(Hppt)] (3) (H₂cpba: 3-(2′-carboxy-phenoxy)-benzoic acid; Hppt: 3-(pyridin-3′-yl)-5-(pyridin-2′′-yl)-1,2,4-triazole), were 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 analyses. X-ray diffraction analyses revealed that Cd(II) ions are linked by ppt^? to form a ladder-shaped structure along the a-axis and further displays a 2-D supramolecular architecture with cpba^2? along the c-axis. In 2, each Zn(ppt)₂ fragment is linked by the nitrogen of pyridin-3′-yl from the neighboring Zn(ppt)₂ forming a V-shaped chain. Compound 3 consists of a ladder structure, in which each {MoO₄} unit is a bridge linking three Zn(Hppt)²⁺ fragments.     

Rearrangement of enol acetates of α-(3,5-dimethyl-1,2,4-triazol-1-yl)-2,4-dichloroacetophenone and α-(1,2,4-triazol-1-yl)-2,4-dichloropropiophenone

At 140 °C in acetic anhydride enol acetates of -(3,5-dimethyl-1,2,4-triazol-1-yl)-2,4dichloroacetophenone and -(1,2,4-triazol-1-yl)-2,4-dichloropropiophenone undergo 1,3and 1,5-rearrangement, respectively.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 1, pp. 182–184, January, 1995.     

Asymmetric Synthesis of （-）-（4R, 5R）-4-[5-（Benzo[1, 3]dioxol-5-yl）-4- hydroxyl- 1-（pyridin-2-yl）-4, 5-dihydro- 1H-pyrazol-3-yl]benzamide

For discovering novel small molecule inhibitors of transforming growth factor-β1(TGF-β1)type-I receptor(ALK5),we designed1,3,5-triaryl-4-hydroxyl-4,5-dihydro-1H-pyrazole(1)as target compound,mimic the structure of SB-431542which is a2-pyridyl substituted triarylimiazole inhibitor of ALK51.Racemic compound1showed moderate ALK5inhibitory activity in luciferase reporter assays[inhibition(%control):0.1umol/L8.79%;1umol/L19.05%].To investigate the influence of the absolute configuration of…     

4-Nitro-2-(1H-tetrazol-1-yl)­phenol

There are two symmetry-independent mol­ecules in the unit cell of the title compound, C₇H₅N₅O₃. The tetrazole and phenyl rings are essentially planar and are not coplanar in either mol­ecule [dihedral angles 30.2 (1) and 7.0 (1)°]. In the structure, four mol­ecules are connected by O—H⃛N bridges, forming four-membered molecular aggregates which are linked together by a complex three-dimensional hydrogen-bond network.     

Novel 2′-(pyridin-4-yl)-5′-(pyridin-2-yl)-1′-(pyridin-2-yl)methylpyrrolidinyl[60]fullerene-hydroxyoxo(5,10,15,20-tetraphenyl-21H,23H-porphynato) molybdenum(V) dyads

Interaction between hydroxyoxo(5,10,15,20-tetraphenylporphyrinato)molybdenum(V) and 2′-(pyridin-4-yl)-5′-(pyridin-2-yl)-1′-(pyridin-2-yl)methylpyrrolidinyl[60]fullerene in toluene has been studied by means of spectrophotometry. The reaction proceeds via two stages: rapidly established equilibrium between the reactants and their molecular complex 1: 1 [K = (1.97 ± 0.52) × 10⁴ L/mol] followed by slow irreversible displacement of hydroxy group into the second coordination sphere to form cationic outer sphere complex (k = 0.26 L s^?1 mol^?1). The effect of fullerene fragment on pyridine fragments coordination has been considered.     

Synthesis and Structure of 2-(1Н-Indol-1-yl)-6-ferrocenyl-4-(2-chloroimidazo[1,2-a]pyridin-3-yl)pyrimidine

A 2,4,6-trisubstituted pyrimidine including a 2-(1H-indol-1-yl) substituent was synthesized by the reaction of 1-ferrocenyl-3-(2-chloroimidazo[1,2-a]pyridin-3-yl)propanone with 2,5-dimethoxytetrahydrofuran. The structure of the synthesized compound was confirmed by IR and ¹Н NMR spectroscopy, and X-ray diffraction analysis. It has been shown that the ferrocene-containing compounds synthesized in the present work all demonstrate intramolecular charge transfer which is evidenced by the observation of the corresponding absorption bands with λ ^abs_max > 480 nm. The oxidation potential of ferrocene (E ^Fc_ox ) in all the compounds is higher than 700 mV.

     

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, {[Zn_(0.5)(H_2L)(tp)_(0.5)(H_2O)]H_2O}_n(1) and {[Zn_2(HL)(btc)(H_2O)]H_2O}_n(2)(H_2L = 3-(1 Hpyrazol-4-yl)-5-(pyridin-3-yl)-1,2,4-triazole, H_2tp = terephthalic acid; H_3 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,Structure and Biological Activities of 2-(1H- 1,2,3-Benzotriazol-1-yl)-1-(4-methylphenyl)-2- (1H-1,2,4-triazol-1-yl)-1-ethanone

IntroductionTriazole derivatives have become the most rapidlyexpanding group of antifungal compounds with advanta-ges of lowtoxicity, high oral bioavailability and broad-spectrum antifungal activity, which can be used againstfungi including most yeasts an…     

Modular synthesis of 1-α- and 1-β-(indol-2-yl)-2'-deoxyribose C-nucleosides

A simple two-step method for the selective preparation of anomerically pure 1α- and 1β-(indol-2-yl)deoxyribose derivatives was developed. The synthesis was based on the Sonogashira reaction of 1α- and 1β-ethynyldeoxyribose and 2-haloanilines followed by a Pd-complex catalyzed cyclization to the corresponding indolyldeoxyribosides.     

Synthesis,Crystal Structure and Fungicidal Activity of N-（4-tert-buty）-5-（1,2,4-triazol- 1-yl）thiazol-2-yl）propionamide

The title compound has been synthesized by the reaction of 4-tert-butyl-5-(1,2,4-triazol-1-yl)-2-aminothiazole with propionic anhydride, and its crystal structure was determined by single-crystal X-ray diffraction. The crystal belongs to the orthorhombic system, space group Pbca with a = 18.441(2), b = 8.3284(9), c = 19.257(2) , Z = 8, V = 2957.5(5) 3, Mr = 279.37, Dc = 1.255 mg/m3, S = 1.033, μ = 0.219 mm-1, F(000) = 1184, the final R = 0.0349 and wR = 0.0876 for 2629 observed reflections(I 2σ(I)). X-ray crystal structure presents the intermolecular N–H···N hydrogen bond, which plays an important role in stabilizing the crystal structure. The preliminary bioassay indicates that the title compound exhibits potent fungicidal activity against R. Solani(25 mg/L) with inhibition rate of 80.0%.     

Synthesis and ozonization of (+)-4α-(1-trimethylsilyloxyethen-1-yl)-2-carene

(+)-4-(1-Trimethylsilyloxyethen-1-yl)-2-carene was synthesized, and the products of its ozonization were identified.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 10, pp. 1984–1987, October, 1995.     

Synthesis,Crystal Structure and Fluorescent Properties of a Cadmium(Ⅱ) Complex with 3-(Pyridin-4-yl)-5-(pyrazin-2-yl)-1H-1,2,4-triazole

Compound [Cd_(1.5)(ppt)Br_2(H_2O)]_(2n)(1),where Hppt = 3-(pyridin-4-yl)-5-(pyrazin-2-yl)-1H-1,2,4-triazole,has been synthesized under hydrothermal conditions and characterized by elemental analysis,IR spectra,powder XRD,and X-ray diffraction.Compound 1 crystallizes in the triclinic system,space group P1 with a = 7.4402(6),b = 8.0570(7),c = 12.8674(11) ?,α = 89.7300(10),β = 89.8570(10),γ = 68.3910(10)°,V = 717.13(10) ?3,Z = 1,Dc = 2.638 g/cm3,μ = 7.824 mm~(-1),F(000) = 534,the final R = 0.0324 and w R = 0.1084 for 2324 observed reflections with I 2σ(I).X-ray diffraction analyses revealed that complex 1 is a 2D layered coordination polymer constructed from the linkage of [Cd_3(μ-Br)_4] trinuclear units with ppt-spacers,and a 3D supramolecular architecture is further assembled in 1 via hydrogen-bonding contacts.Fluorescence measurements show that 1 has medium fluorescent emission at 450 nm.     

5-(Naphth-1-yl)- and 5-[(1,1′-biphenyl)-4-yl]isoxazole-3-carbaldehyde oximes: Synthesis,complexes with palladium,and application in catalysis

1-(Naphth-1-yl)- and 1-[(1,1′-biphenyl)-4-yl-3,4,4-trichloro-3-buten-1-ones were synthesized by acylation of naphthalene and biphenyl with 3,4,4-trichloro-3-butenoyl chloride. Further reaction with hydroxylamine led to 5-(naphth-1-yl)- and 5-[(1,1′-biphenyl)-4-yl]isoxazole-3-carbaldehyde oximes. The latter form complexes with palladium, which possess high catalytic activity in the Suzuki reaction in aqueous and aqueous-alcoholic media.     

X-Ray Structural Analysis of Ethyl [2,2-dimethyl-6-(Δ2-thiazolin-2-yl)-4H-1,4-benzoxazin-3-one-4-yl]butyrate

With the aim of discovering new molecules with K⁺ channel modulating properties, we have synthesized analogues of cromakalim, an important molecule which shows specific affinity toward the K⁺ channels, by replacing the benzopyrane ring with a benzoxazine moiety. As a part of this study, we have synthesized and characterized, in solution and in the solid state as well, the compound ethyl [2,2-dimethyl-6-(²-thiazolin-2-yl)-4H-l,4-benzoxazin-3-one-4-yl]butyrate (V). This compound exhibits in the solid state the following parameters: molecular formula C₁₉H₂₄N₂O₄S, triclinic, space group , M_w = 376.5, a = 12.581(3) Å, b = 5.485(4) Å, c = 14.612(2) Å, = 91.85(2), = 108.9(3), = 82.04(4), V = 944.7 ų, Z = 2, d = 1.323 g·cm^–3. We describe here the synthesis and discuss the solid-state conformation of this new molecule; when tested on rat aorta ring precontracted with phenylephrine, the compound showed a concentration-dependent relaxation comparable to that measured for cromakalin taken as reference drug.     

Synthesis of chiral α-(tetrazol-1-yl)-substituted carboxylic acids

Optically active α-(tetrazol-1-yl)-substituted carboxylic acid OBO-esters were synthesized from the corresponding a-isocyano OBO-esters and trimethylsilyl azide in up to 92% yield. Subsequent acidic hydrolysis proceeds without epimerization and makes it possible to prepare enantiomerically pure α-(tetrazol-1-yl)-substituted carboxylic acids in up to 89% yield.

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Synthesis and hydrazinolysis of β-(1,3,4-oxadiazol-2-yl)pyridines

Cyclization of the hydrazide of 5-ethoxycarbonyl-2,6-dimethylpyridine-3-carboxylic acid by acylation with aromatic or aliphatic acid chlorides with subsequent boiling in POCl₃ or heating in orthoformic acid gave the corresponding ethyl 2,6-dimethyl-5-(5-R-1,3,4-oxadiazol-2-yl)pyridine-3-carboxylate. The cyclization of the reaction products with hydrazine hydrate has been studied. Cyclization of the dihydrazide of 2,6-dimethyl-3,5-pyridinedicarboxylic acid under analogous conditions gave only 3,5-bis-(5-R-1,3,4-oxadiazol-2-yl)-2,6-dimethylpyridines, containing R = 2-FC₆H₄, H.     

Chemoselective Removal of Acyloxy in 1-(Benzotriazole-1-yl)alkyl Esters and Its Application in the Preparation of β-(Benzotriazole-1-yl)alcohols

Mediated by samarium diiodide, 1-(benzotriazole-1-yl)alkyl esters 1 underwent cross-coupling with aldehydes or ketones to afford β-(benzotriazole-1-yl)alcohols 2 exclusively with the selective removal of acyloxy over benzotriazolyl.     

Molecular and crystal structure of (pyrazin-1-ium-1-yl)(perfluoropyridin-4-yl) and (4,4′-bipyridin-1-ium-1-yl)(perfluoropyridin-4-yl)amides

The single crystal X-ray diffraction study of (pyrazin-1-ium-1-yl)(perfluoropyridin-4-yl) and (4,4??-bipyridin)-1-ium-1-yl(perfluoropyridin-4-yl)amides is performed. In all cases, the N⁺-N^? bond length is less than that of the single N_planar.-N_planar. bond, but considerably more than that of the double N=N bond, which indicates a weak involvement of the N^? lone pair of the C₅NF₄N^? group in conjugation with pyrazine or bipyridine moieties. Quantum chemical calculations by DFT/(PBE/L1), B3LYP/L1, and RI-MP2/L1 methods provide the geometry of amides similar to the experimental one. Crystals of (pyrazin-1-ium-1-yl)(perfluoropyridin-4-yl)amide form stacks mainly through F-?? interactions. The stacks are joined in 3D architecture by weak C-H??N and C-H??F hydrogen bonds. In the case of (4,4??-bipyridin)-1-ium-1-yl(perfluoropyridin-4-yl)amide crystals, an essential role is played by the ?? stacking interactions of heteroaromatic rings.