Two Hybrid Compounds Constructed from Vanadate Clusters and Secondary Metal‐Bis(imidazole) Subunits

Two new inorganic–organic vanadate hybrid compounds [Mn(Hbbi)₂(V₄O₁₂)] ( 1 ) and [Cd(Hbbi)₂(V₄O₁₂)] ( 2 ) (bbi = 1,1’‐(1,4‐butanediyl)bis(imidazole)) were hydrothermally synthesized and characterized by elemental analyses, IR spectroscopy, TG and single‐crystal X‐ray diffraction. The two compounds crystallize in monoclinic system, P2₁/c space group with a = 8.556(5) Å, b = 10.761(5) Å, c = 16.917(5) Å, β = 93.032(5) ^o, V = 1555.4(12) Å³, Z = 2, R = 0.0390 for 1 and a = 8.657(5) Å, b = 10.743 (5) Å, c = 16.864 (5) Å, β = 93.81(5)^o, V = 1564.9 (12) Å³, Z = 2, R = 0.0717 for 2 . Single‐crystal X‐ray diffraction analysis reveals that the two compounds are isostructural and both consist of one‐dimensional (1D) chains, which are constructed from vanadate anion clusters and [M(Hbbi)₂]⁴⁺ cation groups [M = Mn^II ( 1 ), Cd^II ( 2 )]. Moreover, the polymeric chains are ultimately packed into a three‐dimensional (3D) supramolecular framework through C–H ··· O and N–H ··· O hydrogen bonding interactions.     

Novel Motif of Hydrogen Bonds in the Water-assisted Supramolecular Self-assembly of 2-acetylamino-6-methylpyridine-N-oxide and Hetero-assembly of 1:1 Co-crystal of o-Phenylenediamine with Catechol

Abstract

Water assisted supramolecular structures of 2-acetylamino-6-methylpyridine-1-oxide (1) and 1:1 complex of o-phenylenediamine with catechol (2) were determined. The crystal structure of 2-acetylamino-6-methylpyridine-1-oxide. H₂O (1), triclinic, a = 7.1276 (6), b = 7.8860 (6), c = 8.9938 (7) Å, α = 100. 143 (2), β = 91.493 (2), γ = 110.972 (1)°, V =462.47 (6) ų, Z = 2, D _calc = 1.323 mg.m^?3(293°K) reveals a novel centrosymmetric supramolecular assembly that is sustained by water molecules linking the dimers of pyridine-1-oxide through C—H…O, N—H…O, N⁺—O^? … H hydrogen bonds. The pyridine rings of the dimers are stacked at 3.473 Å apart, involving π- stacking interactions. Complex (2), C₆H₈N₂.—C₆ H₆O₂. 1/2H₂O crystallises in the monoclinic space group P2/c: a = 9.0498(2), b = 5.2275(1), c = 25.0771(2) A, β = 97.71°, V= 1175.62(4) ų, Z = 4. Refinement led to a final conventional R value of 0.041 for 2016 reflections. In these crystals (2), the water molecules lie on the twofold axis and they are linked to the pyrocatechol molecules through an O—H…O hydrogen bond.     

Synthesis and characterization of the new 22-π aromatic furan-containing macrocycle, “ozaphyrin”

The new 22-π, aromatic “pentaplanar” macrocycle, ozaphyrin ( 6 ), has been synthesized by a McMurry coupling of 5,5′-diformyl-4,4′-dipropyl-2,2′-bipyrrole ( 1 ) with 2,5-bis(5-formyl-4-propyl-2-pyrrolyl)furan ( 5 ). This synthetic pathway to ozaphyrin and its characterization by ¹H nmr spectroscopy, uv-visible spectroscopy, cyclic voltammetry, and X-ray crystallography are described. The structure consists of layers of planar, staggered macrocycles stacked perpendicular to the α-axis. Ozaphyrin crystallizes with four formula units in the monoclinic space group C⁵_2h-P2₁/n in a cell of dimensions a = 10.481(7) Å, b = 17.353(17) Å, c = 18.726(12) Å, and β = 102.84(5)° (108 K). The structure has been refined on F² (5171 unique reflections, 411 variables) to R_w(F_o²) = 0.165. The conventional agreement index R(F) is 0.074 for the 3289 reflections have F_o²>2o(F_o²).     

Two Modifications of NH4HPO3F: Synthesis and Crystal Structure

The α and β modifications of NH₄HPO₃F were synthesized and characterized with single crystal X‐ray diffraction. The crystal structure of α‐NH₄HPO₃F determined at 180 K is monoclinic, space group P2₁/n, with a = 7.4650(1), b = 15.586(2), c = 7.5785(9) Å, β = 108.769(9)°, V = 834.9(2) ų, Z = 8, and R₁ = 0.0376 and wR₂ = 0.0818. β‐NH₄HPO₃F measured at 310 K crystallizes in the triclinic space group, P 1, with a = 7.481(1), b = 7.511(1), c = 7.782(1) Å, α = 84.31(1), β = 84.20(1), γ = 68.67(2)°, V = 404.31(9) ų, Z = 4, and R₁ = 0.0254 and wR₂ = 0.0735. A phase transition was not observed between 180 and 310 K for β‐NH₄HPO₃F. Both modifications of NH₄HPO₄F consist of HPO₃F^– and NH₄⁺ units. Two pairs of two unique anions are linked to each other by O–H…O hydrogen bonds to form cyclic tetramers held together by N–H…O bonds. No O–H…F or N–H…F bonds were observed.     

Synthesis and Structure of N-Ethoxycarbonyl-N′-O-Methoxyphenylthiourea

N-ethoxycarbonyl-N′-o-methoxyphenylthiourea was synthesized and characterized by elemental analysis, TG-DTA analysis, IR, and ¹H NMR spectrum, and single crystal X-ray diffraction analysis. The compound crystallizes as a planar molecule in the monoclinic space group P2(1)/c, with a = 9.690(2)Å, b = 8.595(2)Å, c = 15.944(4)Å, α = 90°, β = 106.467(4)°, γ = 90°, and D_calc = 1.326 g/cm³ for Z = 4. Intramolecular H-bonds promote the stability of the title compound and change the coordination ability of the thiourea ligand. Intermolecular N─H…S H-bonds link pairs of two molecules.     

Microwave-assisted synthesis of 1-{2-[(1-benzyl-1<Emphasis Type="Italic">H</Emphasis>-1,2,3-triazol-4-yl)methoxy]phenyl}-3-(3-aryl-1-phenyl-1<Emphasis Type="Italic">H</Emphasis>-pyrazol-4-yl)prop-2-en-1-ones and their antimicrobial activity

A series of new (E)-1-{2-[(1-benzyl-1H-1,2,3-triazol-4-yl)methoxy]phenyl}-3-(3-aryl-1-phenyl-1H-pyrazol-4-yl)prop-2-en-1-ones (3a–3i) has been synthesized via copper-catalyzed 1,3-dipolar azide-alkyne cycloaddition reaction (CuAAC) of benzyl azide with substituted (E)-3-(3-aryl-1-phenyl-1H-pyrazol-4-yl)-1-[2-(prop-2-ynyloxy)phenyl]prop-2-en-1-ones (2a–2i). The synthesized compounds have been characterized by their IR, ^lH, ¹³C NMR spectra, and mass spectroscopy data. All the compounds have been screened for antimicrobial activity.     

Synthesis,antibacterial, and antioxidant activities of naphthyl-linked disubstituted 1,2,3-triazoles

Here, click synthesis of 15 naphthyl-linked disubstituted 1,2,3-triazoles has been carried out by the reaction between 1-(prop-2-yn-1-yloxy)naphthalene and aromatic azides. The structure elucidation of the synthesized compounds was carried out by FTIR, ¹H NMR, ¹³C NMR, and HRMS techniques. Further, the compound 7f was confirmed by X-ray crystallography (CCDC 1876891). The synthesized compounds were explored for antibacterial activity against Bacillus cereus, Escherichia coli, and Staphylococcus aureus. Biological evaluation of synthesized 1,2,3-triazoles revealed moderate to good antibacterial activity against the tested strains. The antioxidative behavior of synthesized compounds manifested the remarkable free radical scavenging activity using DPPH assay.     

Effects on Coordination of Thioether Sites. 4. Structural Analysis of η3-Tripodal Ligand Manganese(I) Complexes

Crystal structures of a series of manganese(I) complexes containing tripodal ligands were determined. For [η³-{CH₃C(CH₂PPh₂)₂(CH₂SPh)-P,P′,S}Mn(CO)₃]PF₆ ( 1 ): a = 10.856(3) Å, b = 19.698(3) Å, c = 17.596(5) Å, β = 96.17(2)°, monoclinic, Z = 4, P2₁/c, R(F_o) = 0.068, R_w(F_o) = 0.055 for 3617 reflections with I_o > 2σ(I_o). For [η³-{CH₃C(CH₂PPh₂)(CH₂SPh)₂-P,P′,S}Mn(CO)₃]PF₆ ( 2 ): a = 9.890(2) Å, b = 20.403(4) Å, c = 10.269(3) Å, β = 117.44(2)°, monoclinic, Z = 2, P2_l, R(F_o) = 0.050, R_w(F_o) = 0.037 for 1760 reflections with I_o > 2σ(I_o). For [η³-{CH₃C(CH₂PPh₂)₂(CH₂S)-P,P′,S}Mn(CO)₃] ( 4 ): a = 8.191(7) Å, b = 10.495(3) Å, c = 19.858(6) Å, α = 99.61(2)°, β = 96.17(2)°, γ = 92.70(4)°, triclinic, Z = 2, P-I, R(F_o) = 0.048, R_w(F_o) = 0.039 for 2973 reflections with I_o > 2σ(I_o). There is no significant difference in the bond lengths of Mn-S bonds among three species in their crystal structures [2.325(2) Å in 1; 2.358(4) in 2; 2.380(2) in 4], but the better donating ability of thiolate in complex 4 appears on the lower frequencies of its carbonyl stretching absorptions.     

Crystal Structures of Hydrazinium(II) Salts of [SbF6]– and [Sb2F11]–

N₂H₆(Sb₂F₁₁)₂ was synthesized by the reaction of N₂H₆F₂ with excess of SbF₅ in anhydrous hydrogen fluoride (aHF). It crystallizes in the triclinic space group P$\bar{1}$ (No. 2) with a = 6.6467(3) Å, b = 8.3039(4) Å, c = 8.3600(5) Å, α = 76.394(5) ^o, β = 70.161(5) ^o, γ = 70.797(5) ^o, V = 405.90(4) ų at 150 K, Z = 2. When it is redissolved in aHF, it solvolysis with the release of SbF₅ yielding N₂H₆(SbF₆)₂ which crystallizes in the monoclinic C2/c space group (No. 15) with a = 7.3805(3) Å, b = 12.3248(5) Å, c = 10.4992(4) Å, β = 92.218(4) ^o, V = 954.33(7) ų at 150 K, and Z = 8. No other phases were observed in crystallization products when different molar ratios of N₂H₆F₂/SbF₅ (1:1,2:3,1:3) in aHF were used as starting materials.     

Crystal structure of 1:1 Complexes between urea and two crown ether derivatives of phthalic acid, 2,3,5,6,8,9,11,12,14,15-decahydrobenzo[1,4,7,10,13,16]hexaoxacyclo-octadecin-18,19-dicarboxylic acid (i) and 2,3,5,6,8,9,11,12-octahydro-benzo[1,4,7,10,13]pentaoxacyclopentadecin-15,16-dicarboxylic acid (II)

The crystal structures of the titlke compounds have been determined by X-ray diffraction. Urea, I crystallizes in the triclinic PI space group with cell dimensions a = 8.336(2), b = 11.009(2), c = 13.313(2) Å, α = 105.55(3), β = 103.62(3), γ = 104.63(3)° and Z = 2 final R value 0.072 for 2105 observations. Urea, II crystallizes in the orthorhombic P2₁2₁2₁ space group with cell dimensions a = 8.750(2), b = 10.844(3) and c = 21.215(3) Å and Z = 4, final R value 0.083 for 599 observations. All the hydrogen atoms were located in the complex urea, I ; urea molecules form hydrogen bonded dimers about centers of symmetry, these dimers are sandwiched between macrocyclic rings forming one simple and one bifurcated hydrogen bond from the “endo” hydrogen atoms to the ether oxygen atoms. These units are held by hydrogen bonding between the urea molecules and carboxylic acids in two other units; these hydrogen bonds are cyclic involving eight atoms -(N-H(exo)…O(keto)-C-O-H…O(urea)-C)-. Only one carboxylic acid group per molecule takes part in these hydrogen bonds, the other forms a short, 2.490(7) Å, internal bond to the acceptor keto oxygen atom. N(H)…O bonds range from 2.930(7) to 3.206(7) Å, O(H)…O is 2.475(6) Å. In the complex urea, II each urea is hydrogen bonded to three different host molecules and vice versa; the urea “endo” hydrogen atoms bond to the ether oxygen atoms, while both “exo” hydrogen atoms take part in cyclic hydrogen bonds to carboxylic acids. There is not internal hydrogen bond. N(H)…O bonds range from 2.83 to 3.26(2) A and the O-…O bonds are 2.55 and 2.56(2) Å.     

Experimental and Theoretical Studies of 4‐(1‐benzyl‐5‐methyl‐1H‐1,2,3‐triazol‐4‐yl)‐6‐(2,4‐dichlorophenyl)pyrimidin‐2‐amine: A Potential Antibacterial Agent

The title compound ( 1 ), 4‐(1‐benzyl‐5‐methyl‐1H‐1,2,3‐triazol‐4‐yl)‐6‐(2,4‐dichlorophenyl)pyrimidin‐2‐amine (C₂₀H₁₆Cl₂N₆), was synthesized and structurally characterized by elemental analysis, ¹H NMR and ¹³C NMR and single crystal X‐ray diffraction. The compound crystallizes as a colourless needle shaped in the triclinic system, space group P‐1 with cell constants: a = 10.7557(11) Å, b = 12.7078(17) Å, c = 15.511(2) Å, α = 68.029(4)0, β = 86.637(5)0, γ = 87.869(4)0; V = 1962.4 (4) ų, Z = 4. There are two structurally similar but crystallographically independent molecules (A and B) in the asymmetric unit of the title compound, which is linked via N‐H…Cl hydrogen bond. An intramolecular C‐H…N hydrogen also occurs in each molecule. In the crystal, each of independent molecules forms a centrosymmetric dimer with an R²₂(8) ring motifs through a pair of N‐H…N hydrogen bonds. These dimers are further connected by intermolecular N‐H…Cl and C‐H…Cl hydrogen bonds, forming an infinite two dimensional supramolecular network lying parallel to the [010] plane. The molecular geometry was also optimized using density functional theory (DFT/B3LYP) method with the 6‐311G (d, p) basis set and compared with the experimental data. Mulliken population analyses on atomic charges, HOMO‐LUMO energy levels, Molecular electrostatic potential and chemical reactivity of the title compound were investigated by theoretical calculations. The thermo dynamical properties of the title compound at different temperature have been calculated and corresponding relations between the properties and temperature have also been obtained. The in vitro antibacterial activity has been screened against Gram‐positive (Bacillus cerus and Staphylococcus epidermidis) and Gram‐Negative (Escherichia coli, Acinetobacter baumannii and Proteus vulgaris). The results revealed that the compound exhibited good to moderate antibacterial activity.     

Untersuchungen über S?H …︁ S-Wasserstoffbrücken Die Kristallstruktur der Diphenyldithiophosphinsäure bei 140 und 293 K

Die Kristallstruktur der Diphenyldithiophosphinsäure (C₆H₅)₂P(S)SH wurde röntgenographisch bei tiefer Temperatur und Normaltemperatur aus Einkristalldiffraktometerdaten bestimmt und bis zu R-Werten von 0,037 (140 K, (sin Θ)/λ < 0,81 Å^?1) und 0,035 (293 K, (sin Θ)/λ < 0,64 Å^?1) verfeinert. Die Verbindung kristallisiert in der monoklinen Raumgruppe P2₁/c mit den bei 140 K (in Klammern: 293 K) gemessenen Gitterkonstanten a = 9,824(3) (9,887), b = 10,061(3) (10,175), c = 14,342(4) (14,433) Å, β = 122,08(3) (121,73)° und V = 1201,1 (1234,9) ų, Z - 4. Im Kristall sind individuelle Moleküle über fast lineare S? H…?S-Wasserstoffbrückenbindungen zu schraubenförmig gewundenen Ketten verknüpft. Bei 140 K beträgt der S…?S-Abstand innerhalb der Brücke 3,790(1) Å; die weiteren geometrischen Daten der Wasserstoffbrücke sind: d(S? H): 1,25(2), d(S…?H): 2,56(2), d(P? S): 2,077(1), d(P?S): 1,954(1) Å, ? (S? H…?S): 169,5(14), ? (P? S…?S): 98,87(2), ? (P?S…?S): 96,65(2)°. Investigations on Compounds Containing S? H…?S Hydrogen Bonds. Crystal Structure of Diphenyldithiophosphinic Acid at 140 and 293 K The crystal structure of diphenyldithiophosphinic acid (C₆H₅)₂P(S)SH was determined from X-ray diffraction data collected at 140 and 293 K and was refined to R factors of 0.037 (140 K, (sin Θ)/λ < 0.81 Å^?1) and 0.035 (293 K, (sin Θ)/λ < 0.64 Å^?1) respectively. The compound crystallizes in the monoclinic space group P2₁/c with unit cell parameters at 140 K (in parentheses: at 293 K): a = 9.824(3) (9.887), b = 10.061(3) (10.175), c = 14.342(4) (14.433) Å, β = 122.08(3) (121.73)° and V = 1201.1 (1234.9) ų, Z = 4. In the crystalline state individual molecules are linked together by nearly linear S? H…?S hydrogen bonds so that endless helical chains are formed. At 140 K the S…?S distance within the hydrogen bond is 3.790(1) Å; the other distances and angles associated with the bridge are: d(S? H): 1,25(2), d(S…?H): 2,56(2), d(P? S): 2,077(1), d(P?S): 1.954(1) Å, ? (S? H…?S): 169.5(14), ? (P? S…?S): 98.87(2), ? (P? S…?S): 96.65(2)°.     

The Cluster Compounds Ag[W6Br14] and Ag2[W6Br14]

The reaction of W₆Br₁₂ with AgBr in evacuated silica tubes (temperature gradient 925 K/915 K) yielded brownish black octahedra of Ag[W₆Br₁₄] ( I ) and yellowish green platelets of Ag₂[W₆Br₁₄] ( II ) both in the low temperature zone. ( I ) crystallizes cubically (Pn3 (no. 201); a = 13.355 Å, Z = 4) and ( II ) monoclinically (P2₁/c (no. 14); a = 9.384 Å, b = 15.383 Å, c = 9.522 Å, β = 117.34°, Z = 2). Both crystal structures contain isolated cluster anions, namely [(W₆Brⁱ₈)Br^a₆]^1– and [(W₆Brⁱ₈)Br^a₆])]^2–, respectively, with the mean distances and angles: ( I ) d(W–W) = 2.648 Å, d(W–Brⁱ) = 2.617 Å, d(W–Br^a) = 2.575 Å, d(Brⁱ…Brⁱ) = 3.700 Å, d(Brⁱ…Br^a) = 3.692 Å, ∠W–Brⁱ–W = 60.78°. ( II ) d(W–W) = 2.633 Å, d(W–Brⁱ) = 2.624 Å, d(W–Br^a) = 2.613 Å, d(Brⁱ…Brⁱ) = 3.710 Å, d(Brⁱ…Br^a) = 3.707 Å, ∠W–Brⁱ–W = 60.23°. The Ag⁺ cations are trigonal antiprismatically coordinated in ( I ) with d(Ag–Br) = 2.855 Å, but distorted trigonally planar in ( II ) with d(Ag–Br) = 2.588–2.672 Å. The structural details of hitherto known compounds with [W₆Br₁₄] anions will be discussed.     

Synthesis and Comprehensive Characterization of Hydrated Alkaline Earth Metal Salts of 5‐Amino‐1H‐tetrazole

Hydrated alkaline earth metal salts of 5‐amino‐1H‐tetrazole ( B ) were synthesized by reaction of B with a suitable metal hydroxide in water. All compounds were fully characterized by analytical (elemental analysis and mass spectrometry) and spectroscopic (IR, Raman, ¹H and ¹³C NMR) methods. Additionally, the crystal structures of the magnesium [ 1· 4H₂O: triclinic, P$\bar {1}$ , a = 5.940(1) Å, b = 7.326(1) Å,c = 7.383(1) Å, α = 106.10(1)°, β = 106.51(1)°, γ = 111.85(1)°, V = 258.0(1) ų], calcium [ 2· 6H₂O: monoclinic, P2₁/m, a = 6.904(1) Å,b = 6.828(1) Å, c = 10.952(2) Å, β = 94.50(2)°, V = 514.6(1) ų], and strontium [ 3· 6H₂O: orthorhombic, Cmcm, a = 6.987(1) Å, b = 28.394(2) Å, c = 7.007(1) Å, V = 1390.3(2) ų] were determined by low temperature X‐ray diffraction. Additionally, the (gas phase) structure of the 5‐amino‐1H‐tetrazole anion ([ B ]^–) was also studied by natural bond orbital (NBO) analysis [B3LYP/6‐31+G(d,p)]. Lastly, standard tests were used to determine the sensitivity towards impact, friction, and electrostatic discharge of the compounds and the thermal stability was assessed by differential scanning calorimetry (DSC) analysis.     

Kristallstrukturen und thermisches Verhalten von Metalldihydrogenphosphat‐HF‐Addukten MH2PO4 · HF (M = K,Rb, Cs) mit Wasserstoffbrückenbindungen vom Typ F–H…O

Structures and Thermal Behaviour of Alkali Metal Dihydrogen Phosphate HF Adducts, MH₂PO₄ · HF (M = K, Rb, Cs), with Hydrogen Bonds of the F–H…O Type Three HF adducts of alkali metal dihydrogen phosphates, MH₂PO₄ · HF (M = K, Rb, Cs), have been isolated from fluoroacidic solutions of MH₂PO₄. KH₂PO₄ · HF crystallizes monoclinic: P2₁/c, a = 6,459(2), b = 7,572(2), c = 9,457(3) Å, β = 101,35(3)°, V = 453,5(3) ų, Z = 4. RbH₂PO₄ · HF and CsH₂PO₄ · HF are orthorhombic: Pna2₁, a = 9,055(3), b = 4,635(2), c = 11,908(4) Å, V = 499,8(3) ų, Z = 4, and Pbca, a = 7,859(3), b = 9,519(4), c = 14,744(5) Å, V = 1102,5(7) ų, Z = 8, respectively. The crystal structures of MH₂PO₄ · HF contain M⁺ cations, H₂PO₄^– anions and neutral HF molecules. The H₂PO₄^– anions are connected to layers by O–H…O hydrogen bonds (2,53–2,63 Å), whereas the HF molecules are attached to the layers via very short hydrogen bonds of the F‐H…O type (2,36–2,38 Å). The thermal decomposition of the adducts proceeds in three steps. The first step corresponds to the release of mainly HF and a smaller quantity of water. In the second and third steps, water evolution caused by condensation of dihydrogen phosphate is the dominating process whereas smaller amounts of HF are also released.     

Metabolites of microorganisms. 144th communication. The crystal and molecular structure of 3-hydroxy-4-methylproline

A new amino acid isolated from the acid hydrolysate of the antibiotic Echinocandin B is shown by X-ray analysis to be 2,3–trans-3,4-cis-3-hydroxy-4-methylproline. The crystals are orthorhombic, a = 5.633 Å, b = 8.760 Å, c = 14.314 Å, Z = 4, space group P2₁2₁2₁. The structure was determined by direct methods and refined by least-squares analysis to a final R value of 0.032 for 532 reflections. The molecule exists as a zwitterion forming one O? H…O and two N? H…O hydrogen bonds.     

Synthesis and structures of two hydrazone compounds derived from 4-methylbenzohydrazide

Two hydrazone compounds N′-(2,4-dichlorobenzylidene)-4-methylbenzohydrazide monohydrate (1) and 2-chloro-5-nitro-N′-(4-methylbenzylidene)benzohydrazide (2) derived from 4-methylbenzohydrazide with different benzaldehydes are synthesized and characterized by physicochemical methods and single crystal X-ray diffraction. Compound 1 crystallizes in the orthorhombic space group P2₁2₁2₁ with unit cell parameters a = 4.714(2) Å, b = 13.093(3) Å, c = 24.754(3) Å, V = 1527.9(8) ų, Z = 4, R ₁ = 0.0812, and wR ₂ = 0.1623. Compound 2 crystallizes in the monoclinic space group Cc with unit cell parameters a = 11.564(2) Å, b = 13.271(2) Å, c = 9.462(2) Å, β = 96.860(2)°, V = 1441.7(4) ų, Z = 4, R ₁ = 0.0461, and wR ₂ = 0.0896. The crystals of the compounds are stabilized by intermolecular hydrogen bonds as well as π…π stacking interactions.     

1,3-Oxazole-isoniazid hybrids: Synthesis,antitubercular activity,and their docking studies

A series of novel N′-([2-aryl-5-methyl-1,3-oxazole-4-yl]methylene)isonicotino/nicotino hydrazides 10a-l were prepared by the condensation reaction of 2-aryl-5-methyl-1,3-oxazole-4-carbaldehydes 8a-f with the corresponding isonicotino/nicotino hydrazides 9a/9b . The structures of the new compounds were elucidated by various spectroanalytical techniques, including IR, ¹H NMR, ¹³C NMR, elemental (C,H,N), and mass analysis. All the newly prepared INH-1,3-oxazole hybrids were evaluated for their in vitro antitubercular activity against Mycobacterium tuberculosis H37Rv. Among all the synthesized hybrids, compounds 10c and 10i derivatives displayed highest antitubercular activity with minimal inhibitory concentration 1.56 μg/mL. Further, molecular docking studies against the InhA enzyme were carried out to understand the interactions between potent hybrids and the target enzyme. Thus, these kind hybrids have the potentiality for the discovery of new antitubercular agents for deployment in the control and eradication of tuberculosis.     

Synthesis,Crystal Structure,and Luminescence of a Three-Dimensional Supramolecular Compound Based on a Dinuclear Tin Cluster

A three-dimensional (3D) supramolecular compound, [(phen)LSnS]₂·(H₂O)₂ (phen = 1,10-phenanthroline, L = mercaptoacetic acid), has been synthesized and the crystal structure was determined by a single crystal X-ray diffraction study. 1 is triclinic, space group P-1 with a = 6.695(1) Å, b = 10.929(2) Å, c = 12.117(2) Å, α = 114.55(3)°, β = 93.53(2)°, γ = 104.06(3)°, and Z = 1. The dinuclear cluster of [(phen)LSnS]₂ and H₂O are linked into a 3D supramolecular framework by a combination of O[sbnd]H…O, C[sbnd]H…O hydrogen bonds and π–π stacking interactions. Its luminescence property is discussed.     

Halogenometallate von Übergangselementen mit Kationen stickstoffhaltiger heterocyclischer Basen. I. Die Kristallstrukturen von 1,4-Dimethylpiperazinium-tetrachlorocobaltat(II) und -zinkat(II), (dmpipzH2)[MIICl4] (M = Co,Zn)

Halogenometalates of Transition Elements with N-heterocyclic Base Cations. I. The Crystal Structures of 1,4-Dimethylpiperazinium Tetrachlorocobaltate(II) and -zincate(II), (dmpipzH₂)[M^IICl₄] (M = Co, Zn) The compounds (dmpipzH₂)[M^IICl₄] crystallize in the monoclinic space group P2₁/m with a = 6.133(1), b = 14.306(1), c = 6.902(1) Å, β = 90.54(2)°, Z = 2 for M = Co and with a = 6.141(1), b = 14.282(1), c = 6.907(1) Å, β = 90.60(2)°, Z = 2 for M = Zn. The structures consist of tetrahedra [MCl₄]^2? and centrosymmetric cations (dmpipzH₂)²⁺ in the chair form. Bifurcated hydrogen bridging bonds of the N? H …? Cl type connect the nitrogen atom to two chloride ions. Two short distances C …? Cl are interpreted in terms of C? H …?Cl hydrogen bridges.