One Dimensional Hydrogen Bonded Arrangement in New Schiff-Base Compound (<Emphasis Type="Italic">E</Emphasis>)-2-(2,5-dimethoxybenzylideneamino)phenol (1): Synthesis,Characterization, Crystal Structure and Conformational Studies

Abstract  

New Schiff-base compound (E)-2-(2,5-dimethoxybenzylideneamino)phenol (1) was synthesized and characterized by elemental analyses, FT-IR and ¹H-NMR spectroscopy and single crystal X-ray diffraction. Molecular orbital calculation has been carried out for 1 by using HF method at 6-31G basis set. The title compound 1 crystallizes in monoclinic system, space group C2/c, with a = 19.4581(13) ?, b = 9.5805(5) Ǻ, c = 13.8431(7) Ǻ, β = 93.471(2)°, V = 2575.9(3) Ǻ³ and Z = 8. In the crystal structure two molecules are stabilized by a pair of intermolecular O1–H1···N1ⁱ hydrogen bonds. The dimeric units are further linked via C6–H6···O3ⁱⁱ hydrogen bond.     

Synthesis,Characterization and Crystal Structures of <Emphasis Type="Italic">N</Emphasis>′-(5-Bromo-2-hydroxybenzylidene)-2-fluorobenzohydrazide in Unsolvated and Monohydrate Forms

Abstract  

A new hydrazone derivative, N′-(5-bromo-2-hydroxybenzylidene)-2-fluorobenzohydrazide (BFBH), has been prepared and crystallized from absolute methanol and 95% ethanol, respectively, yielding unsolvated and monohydrate forms of the compound, viz. BFBH (1) and BFBH·H₂O (2). The two forms of the compound were characterized by elemental analysis, IR spectra, ¹HNMR spectra, and X-ray single crystal structural determination. The unsolvated form of the compound crystallizes in the monoclinic space group P2₁/c with unit cell dimensions a = 6.879(1) ?, b = 28.911(2) ?, c = 8.724(1) ?, β = 127.685(2)o, V = 1373.1(3) Ǻ³, Z = 4, R ₁ = 0.0569, and wR ₂ = 0.1352. The monohydrate forms of the compound crystallizes in the monoclinic space group P2₁/c with unit cell dimensions a = 14.873(3) ?, b = 7.265(1) ?, c = 13.043(2) ?, β = 96.281(2)o, V = 1400.9(4) Ǻ³, Z = 4, R ₁ = 0.0402, and wR ₂ = 0.0890. The two structures are similar to each other, except for the presence of a water molecule in (2).     

Synthesis,Characterization and Bioactivity Research of a Derivative of Secnidazole: 1-(2-Chloropropyl)-2-methyl-5-nitro-1<Emphasis Type="Italic">H</Emphasis>-imidazole

Abstract  

A secnidazole derivative, 1-(2-chloropropyl)-2-methyl-5-nitro-1H-imidazole (1), was synthesized and its single crystals were successfully grown in the mixture of ethanol/chloroform (3:1) by slow evaporation at room temperature. Its structure was confirmed by ¹H NMR, ¹³C NMR, mass spectra, elemental analyses and X-ray single crystal diffraction. Crystal structure analysis revealed that 1 crystallized in the triclinic, space group P [`1] \overline{1} with the following unit cell parameters: a = 6.5339(7) Ǻ, b = 7.5487(8) Ǻ, c = 9.7238(10) Ǻ, α = 92.894°(2), β = 96.165(2)°, γ = 102.710°(2), V = 463.78(8) ?³, Z = 2. Furthermore, this compound exhibited better anti-urease activity than secnidazole and acetyl-hydroxy acid when evaluated for antimicrobial activity against Helicobacter pylori.     

Synthesis,Crystal Structure and Thermal Behavior of a New Polynitrile N,N,N′,N′-tetra(2-cyanoethyl)-1,4-bis(3-aminopropyl)piperazine

Abstract  

A new polynitrile, N,N,N′,N′-tetra(2-cyanoethyl)-1,4-bis(3-aminopropyl)piperazine, was synthesized by the nucleophilic addition reaction of 1,4-bis(3-aminopropyl)piperazine and acrylonitrile for the first time. The title compound was characterized by elemental analysis, IR spectrum, and its crystal structure determined by X-ray single-crystal diffraction. The compound crystallizes in the monoclinic system with space group P2 ₁/c and a = 8.6195(12), b = 9.300(14), c = 16.221(2) ?, β = 97.824(2)°, V = 1288.2(3) ?³, D _c  = 1.064 g cm⁻³, M _r  = 412.59, Z = 2, F(000) = 448, μ = 0.067 mm⁻¹. The TG–DTA analysis revealed that the title compound possesses relatively good thermal stability under 220 °C.     

Bis[(2,3,4-Trimethoxy-Benzylidenepropylideneamino)Phenyl]Ether: Synthesis,Characterization and Crystal Structure

Abstract  

New Schiff base compound bis[(2,3,4-trimethoxy-benzylidenepropylideneamino)phenyl]-ether (1) was synthesized and characterized by elemental analyses (CHN), FT-IR and ¹H-NMR spectroscopy and single-crystal X-ray diffraction. The title compound 1 crystallizes in triclinic system, space group P-1, with a = 6.8255(4) Å, b = 10.4346(4) Å, c = 19.4166(8) Å, α = 86.588(3)°, β = 85.019(4)°, γ = 89.042(4)°, V = 1375.12(11) Å³ and Z = 2. It displays a trans configuration about the C=N double bonds.     

Synthesis, Crystal Structures and Fluorescence Property of Bis(benzimidazol-2-yl)methane Dichloride

Abstract  

The title compound, a salt of C₁₅H₁₃N₄ ²⁺2Cl⁻, was synthesized and determined by X-ray crystallography. It crystallizes in the orthorhombic system, space group Pbcn, with lattice parameters a = 9.973(2) ?, b = 9.5012(19) ?, c = 15.574(3) ?, V = 1475.8(5) ?³, Z = 4, C₁₅H₁₃Cl₂N₄, Mr = 320.19, Dc = 1.441 g/cm³. In the crystal structure, the Cl⁻ anion interact with the same benzimidzaole through two kinds of hydrogen bonds forming a 1D hydrogen-bonded chain, two 1D hydrogen-bonded chain cross with each other and form 2D layer structure. The EA, UV, IR and TG-DTG were studied and the possible structures of the title compound were speculated. Moreover, the fluorescence of the title compound was studied. The results reveal that it can emit purple fluorescence in DMF solvent.     

Crystal Structure of 2-(4,5-Bis(4-methoxyphenyl)-5<Emphasis Type="Italic">H</Emphasis>-chromeno[4,3-<Emphasis Type="Italic">b</Emphasis>]pyridin-2-yl)phenol

Abstract  

The title compound 2-(4,5-bis(4-methoxyphenyl)-5H-chromeno[4,3-b]pyridin-2-yl)- phenol (C₃₂H₂₅NO₄, Mr = 487.53) was synthesized and crystallized. The crystal belongs to monoclinic, space group P2(1)/c with a = 12.4170 (11), b = 18.313 (2), c = 11.7103 (10) ?, β = 111.569(2)°, V = 2476.4(4) ?³, Mr = 487.53, Z = 4, Dc = 1.308 g/cm³, μ(MoK _α ) = 0.086 mm⁻¹, F(000) = 1024, the final R ₁ = 0.0632 and wR ₂ = 0.1454. X-ray analysis reveals that the atoms of C(1), C(2), C(3), C(4), C(5) and N(1) form a planar six-membered ring, while the atoms of C(1), C(2), C(6), C(7), C(12) and O(1) form a six-membered ring of envelope conformation.     

Spectroscopic Studies and Structure of 4-(3-Benzoylthioureido)benzoic Acid

Abstract  

4-(3-Benzoylthioureido)benzoic acid has been synthesized from the reaction of 4-aminobenzoic acid with benzoyl isothiocyanate. The title compound has been characterized by elemental analysis, MS, FT-IR, ¹H-NMR, ¹³C-NMR and UV–Visible techniques. The structure of the compound has also been examined crystallographically. The title compound crystallizes in the triclinic space group P-1 with a = 3.969(1), b = 13.039(1), c = 13.504(1) ?, α = 96.50(1)°, β = 92.25(1)°, γ = 94.94(1), V = 691.0(1) ?³ and D _x  = 1.444 g cm⁻³, respectively. The crystal structure has been solved by direct methods and refined by full-matrix least squares and found R ₁ = 0.031 and wR ₂ = 0.081 for 2909 observed reflections [I > 2σ(I)].     

Synthesis,Characterization and Antibacterial Activity of <Emphasis Type="Italic">N</Emphasis>-(<Emphasis Type="Italic">N</Emphasis>-Acetic Acid-yl-Phthalimide-5-yl) Maleamic Acid Dihydrate

Abstract  

The compound N-(N-acetic acid-yl-phthalimide-5-yl) maleamic acid (C₁₄H₁₀N₂O₇, M _r  = 318) was synthesized and its structure was characterized by elemental analysis, ¹H NMR and IR spectra. The single crystal of the title compound (C₁₄H₁₄N₂O₉, M _r  = 354.27) was cultured and its structure was determined by single crystal X-ray diffraction. The crystal belongs to monoclinic system, space group P21/c with a = 14.3859(19), b = 12.5835(18), c = 8.6934(15) ?, β = 102.824(2)°, V = 1534.5(4) ?³, Z = 4, D _c  = 1.534 g cm⁻³, μ(Mo Kα) = 0.131 mm⁻¹, F(000) = 736. The final refinement gave R = 0.0652, wR(F ²) = 0.1239 for 2,703 observed reflections with I > 2σ(I). X-ray diffraction analysis reveals that the asymmetric unit of the title compound contains one N-(N-acetic acid-yl-phthalimide-5-yl) maleamic acid molecule and two water molecules. One of the two water molecules is disordered. The phthalimide group is essentially planar. The crystal structure of the title compound is stabilized by N–H…O and O–H…O hydrogen bonds interactions. The compound N-(N-acetic acid-yl-phthalimide-5-yl) maleamic acid possesses moderate antibacterial activity.     

Structure of a New Bioactive Agent Containing Combined Antibacterial and Antifungal Pharmacophore Sites: 4-{[(<Emphasis Type="Italic">E</Emphasis>)-(5-Bromo-2-hydroxyphenyl)methylidene]amino}-<Emphasis Type="Italic">N</Emphasis>-(5-methyl-1,2-oxazol-3-yl)benzenesulfonamide

Abstract  

The title compound (3), C₁₇H₁₄BrN₃O₄S, is a Schiff base compound of 5-bromosalicylaldehyde (1) and sulfamethoxazole (2). The structure of (3) was determined by spectral (IR, ¹H and ¹³C NMR), elemental analyses and X-ray diffraction data. Compound (3) crystallizes in the monoclinic space group C2/c, with a = 31.936(3), b = 6.2571(5), c = 16.903(1) ?, β = 94.867(8), V = 3365.5(5) ?³, Z = 8. In the molecule of compound (3), the molecule is bent at the S atom with a C–SO₂–NH–C torsion angle of −86.3(3)°. Pairs of molecules, related by inversion centres, form intermolecular N–H···N hydrogen bonds to produce a dimer. An intramolecular phenolic O–H···N hydrogen bond is also formed. Intermolecular hydrogen bonding and π–π stacking hold the molecules together. The average distance between stacked benzene ring planes is 3.625(2) ?.     

Synthesis,Crystal and Calculated Structure,and Biological Activity of 2-((6-Bromo-2-methoxyquinolin-3-yl) (phenyl)methyl)-2,3,7,7a-tetrahydro-3a,6-epoxyisoindol-1(6H)-one

Abstract  

The title compound, C₂₅H₂₁BrN₂O₃, was synthesized and structurally characterized by elemental analysis, IR, MS, ¹H NMR and single crystal X-ray diffraction. The crystal is of orthorhombic system, space group Pbca with a = 11.706(2) ?, b = 18.038(4) ?, c = 20.369(4) ?, α = 90.00°, β = 90.00°, γ = 90.00°, V = 4301.0(15) ?³, Z = 8, Dc = 1.474 g/cm³, F (000) = 1952.0, μ(MoKα) = 1.941 mm⁻¹, the final R ₁ = 0.0670 and wR ₂ = 0.2319 for reflections with I > 2σ(I). The crystal structure is stabilized by un-classical hydrogen-bonding C–H···O forming a three-dimensional network. The optimized geometric bond lengths and bond angles obtained by using density functional theory have been compared with X-ray diffraction values. In addition, the preliminary biological test showed that the title compound had anti-Mycobacterium phlei 1180 activity.     

Synthesis,Crystal Structure and Spectroscopic Properties of an Oximato Bridged Cu(II) Dimer

Abstract  

Schiff-base condensation of a equimolar proportion of diacetyl-monoxime monohydrazone and 1-methylimidazole-2-carboxaldehyde in methanol gives rise to the imidazole azine, 3-(1-methylimidazol-2-yl)methylenehydrazonobutan-2-one oxime(HL). Reaction of 1:1 stoichiometric proportion of HL with copper(II)perchlorate hexahydrate in methanol yields a dimeric oximato bridged copper compound, [Cu₂L₂(H₂O)₂](ClO₄)₂ (1). The compound is characterized by C, H and N analyses, FT-IR, ESI–MS, conductivity measurement, UV–Vis spectra and X-ray single crystal diffraction. The title compound (1) crystallizes in the monoclinic space group P2₁/c with a = 6.8533 (8), b = 18.413 (2), c = 11.7399 (14) ?, β = 93.685 (2)°, V = 1478.4 (3) ?³ and Z = 2. The geometry around each copper center is distorted square pyramidal. The copper(II) dimer shows antiferromagnetic interaction mediated by symmetric disposition of oximato groups.     

Crystal Structure of <Emphasis Type="Italic">N</Emphasis>-(2-Pyridylmethylene)benzene-1,4-diamine

Abstract  

The crystal structure of amino containing Schiff base, N-(2-pyridylmethylene)benzene-1,4-diamine, was determined via X-ray diffraction analysis. The title compound crystallizes in orthorhombic system, space group Pc2 ₁ n, with unit cell dimensions a = 5.8945(6), b = 11.9233 (10), c = 14.5356 (16) ?, V = 1021.59 (18) ?³, Z = 4. The molecules are linked by intermolecular N–H···N hydrogen bonds to form supramolecular sheets along with the bc crystallographic plane. The crystal structure is further stabilized by C–H···π stacking interactions.     

Structure of 2-[(Phenyl)-(3,5-Dimethyl-Pyrazol-1-yl)-Methyl]-Malonic Acid Diethyl Ester

Abstract  

The titled new functionalized ligand of type 2-[(phenyl)-(3,5-dimethyl-pyrazol-1-yl)-methyl]-malonic acid diethyl ester (4) is prepared in good yield through condensation of 3,5-dimethyl-pyrazole, with 2-arylidene-malonic acid diethyl esters 3. The structure of 4 was determined by spectral (IR, ¹H and ¹³C NMR), elemental analyses and X-ray diffraction data. The title compound (4) crystallizes in the monoclinic space group P2₁/a, with a = 7.9253 (2), b = 17.1299 (5), c = 13.4522 (4) ?, β = 90.220 (2)°, V = 1,826.25 (9) ?³, Z = 4 and with R _int = 0.021. The molecular conformation shows two possible pockets ready to coordinate two metal atoms. The crystal structure of (4) is stabilized by inter-molecular C–H⋯O and C–H⋯N hydrogen bonding.     

Synthesis and Crystal Structure of Bis(μ3-4-Oxapentan-2-onato)-Tetrakis(μ2-4-Oxapentan-2-onato)-Tetra-Magnesium Dichloride Dichloromethane

Abstract  

A new magnesium alkoxide which posses centrosymmetric tetranuclear structure derived from 1-methoxy-2-propanol, a functionalized alcohol containing asymmetric carbon. X-ray analysis of single crystal shows an open dicubane-like structure with triple-bridging alkoxo groups between alternating five- and six-coordinated magnesium atoms. There are six alkoxo bridging groups in which two of them bridge three metal centers and the other four bridge two. All of the etheric-oxygens are coordinated to magnesium and provide a rigid structure. Two chlorine atoms are bonded to five-coordinated magnesium. This compound crystallizes in the monoclinic system with a = 10.040(6) Ǻ, b = 14.004(9) Ǻ, c = 15.344(5) Ǻ, β = 95.55(9)˚, Z = 2 and V = 2147 Ǻ³ in the space group of P2₁/n.     

Synthesis and Crystal Structure of a Complex of Palladium(II) with 2-Hydroxyimino-3-(2-hydrazonopyridyl)-butane

Abstract  

Schiff-base condensation of an equimolar proportion of diacetyl-monoxime and 2-hydrazino pyridine in methanol gives rise to 2-hydroxyimino-3-(2-hydrazonopyridyl)-butane (HL). The ligand has been characterised by FT-IR, ¹H NMR and UV–Vis spectra. Reaction of 1:1 stoichiometric proportion of HL with Na₂[PdCl₄] in methanol affords a mononuclear palladium(II) compound, [PdLCl]·H₂O (1). The compound is characterised by C, H and N analyses, FT-IR, conductivity measurement, UV–Vis spectra, thermal analysis and magnetic susceptibility measurement. The X-ray crystal structure of the title compound (1) has been determined. The compound crystalises in the triclinic space group P[`1] P\overline{1} with a = 7.3033(3), b = 9.4139(4), c = 9.4445(5) ?, α = 79.789(3), β = 68.285(2), γ = 77.978(3)o, V = 586.42(5) ?³ and Z = 2. Pd(II) is in ‘N₃Cl’ coordination chromophore. The geometry around Pd(II) is square-planar. The compound is essentially diamagnetic.     

Synthesis,Crystal Structure Properties of {μ-Nitrato-[<Emphasis Type="Italic">N</Emphasis>,<Emphasis Type="Italic">N</Emphasis>′-ethylene-bis(3-methoxysalicylideneimin) diaqua nitrato Cu(II)La(III)]nitrat}

Abstract  

The [μ-NO₃-LCuLa(NO₃)·(H₂O)₂]NO₃ (I) complex has been prepared and characterized by single crystal X-ray diffraction properties. The title compound crystallizes in the monoclinic system, space group P 2₁/c, with a = 9.1699(4), b = 21.6796(8), c = 13.7068(6) ?, α = γ = 90o, β = 111.308(3)°, V = 2538.63 (18) ?³ and Z = 4. The unit cell contains four discrete the title compounds. The central region is occupied by Cu^II and La^III ions which are brigged by two phenolato oxygen atoms of ligand. The intramolecular La–Cu distance is 3.5016 (3) Ǻ. The copper (II) ion is in a distorted square pyramidal geometry with the imino nitrogen atoms N1 and N2, and the phenolic oxygen atoms O2 and O3 forming the square base. The La^III ion is deca coordinated.     

Synthesis and Crystal Structure of Ethyl 2-[4-(acetylamino)phenoxy]-2-methylpropanoate, A Potential Anti-inflammatory and Antidyslipidemic Hybrid

Abstract  

The compound ethyl 2-[4-(acetylamino)phenoxy]-2-methylpropanoate (acetamidofibrate) was prepared by reaction of paracetamol with ethyl 2-bromo-2-methylpropionate. It was characterized by elemental analysis, NMR (¹H, ¹³C) spectroscopy, and single-crystal X-ray diffraction. This compound is of interest with respect to its potential bioactivity as analgesic and antidyslipidemic agent. The compound crystallizes in the monoclinic space group P2(1)/c with unit cell dimensions a = 8.2435(8), b = 9.3390(9), c = 18.2823(18) ?, β = 91.123(2)°, V = 1407.2(2) ?³, Z = 4, R ₁ = 0.0465, and wR ₂ = 0.1055. The crystal structure is stabilized by N–H···O = C and C–H···O hydrogen-bonding interactions that interconnect molecules into chains running along b axis. The preliminary in silico screening shown that title compound could posse’s antidiabetic, anti-inflammatory, hypolipemiant and anti-atherosclerosis effects.     

Synthesis,Characterization and Antibacterial Activity of <Emphasis Type="Italic">N</Emphasis>-(2,3,4-Trimethoxy-6-methylbenzylidene)-2-methyl-benzenamine

Abstract  The title compound N-(2,3,4-trimethoxy-6-methylbenzylidene)-2-methyl-benzenamine (C₁₈H₂₁NO₃, M _r = 299.36) was synthesized and characterized by elemental analysis, IR spectra and single crystal X-ray diffraction. The crystal belongs to monoclinic, space group P2₁/n, with a = 7.2804(5), b = 8.5909(9), c = 26.117(3) ?, β = 92.056(2)°, V = 1,632.4(3) ?³, Z = 4, D _c = 1.218 g cm⁻³, λ = 0.71073 ?, μ(Mo Kα) = 0.083 mm⁻¹, F(000) = 640. The final refinement gave R = 0.0497, wR(F ²) = 0.1157 for 2,879 observed reflections with I > 2σ(I). X-ray diffraction analysis reveals that the dihedral angle between the two phenyl rings is 25.9 (2)°. The molecule adopts a trans configuration about the central C=N functional bond. The crystal structure is stabilized by C–H…O hydrogen bonds and π–π stacking interactions. The title compound possesses moderate antibacterial activity. Graphical Abstract  The title compound N-(2,3,4-trimethoxy-6-methylbenzylidene)-2-methyl-benzenamine (C₁₈H₂₁NO₃, M _r = 299.36) was synthesized and characterized by elemental analysis, IR spectra and single crystal X-ray diffraction. The crystal belongs to monoclinic, space group P2₁/n, with a = 7.2804(5), b = 8.5909(9), c = 26.117(3) ?, β = 92.056(2)°, V = 1,632.4(3) ?³, Z = 4, D _c = 1.218 g cm⁻³, λ = 0.71073 ?, μ(Mo Kα) = 0.083 mm⁻¹, F(000) = 640. The final refinement gave R = 0.0497, wR(F ²) = 0.1157 for 2,879 observed reflections with I > 2σ(I). X-ray diffraction analysis reveals that the dihedral angle between the two phenyl rings is 25.9 (2)°. The molecule adopts a trans configuration about the central C=N functional bond. The crystal structure is stabilized by C–H…O hydrogen bonds and π–π stacking interactions. The title compound possesses moderate antibacterial activity.      

Synthesis and Crystal Structure of 3-Methyl-4-phenyl-5-(2-pyridyl)-1,2,4-triazole

Abstract  

The title compound, 3-methyl-4-phenyl-5-(2-pyridyl)-1,2,4-triazole was synthesized by reaction of diphenylphosphazoanilide with N-acetyl-N′-(2-pyridoyl)hydrazine. Crystals suitable for X-ray analysis were obtained from a mixed solution of water and ethanol in a one-to-one volume ratio. The crystal is orthorhombic, space group P2₁2₁2₁ with crystallographic parameters: a = 19.414(4) Å, b = 17.172(3) Å, c = 7.4850(15) Å, β = 90.00°, μ = 0.079 mm⁻¹, V = 2495.3(8) Å³, Z = 8, Dc = 1.258 g/cm³, F(000) = 992, T = 295(2) K. The X-ray results showed that in the crystal structure of the title compound, the 1,2,4-triazole, pyridine and benzene rings are not coplanar.