A one-pot synthesis and X-ray crystallographic and computational analyses of methyl-2,4-dimethoxysalicylate — a potential anti-tumour agent

2004 ◽  
Vol 82 (7) ◽  
pp. 1179-1185 ◽  
Author(s):  
Hossein A Dabbagh ◽  
Nader Noroozi-Pesyan ◽  
Brian O Patrick ◽  
Brian R James
Keyword(s):  
Hydrogen Bonds ◽  
Solid Phase ◽  
Carbonyl Oxygen ◽  
One Pot ◽  
Oh Groups ◽  
X Ray ◽  
A Value ◽  
Intramolecular Hydrogen ◽  
Computational Analyses ◽  
Thermal Decarboxylation

The thermal decarboxylation of 2-methoxycarbonyl-5-(4′-nitrophen-oxy)tetrazole (1a) with the electron-rich, aromatic compounds (anisole, N,N-dimethylaniline, 1,4-dimethoxybenzene, and 1,3,5-trimethoxybenzene), neat or in polar solvents (DMSO, DMF, and CH3CN), is investigated. The solid phase thermal decomposition of a mixture of 1a, 1,3,5-trimethoxybenzene, and a Lewis acid (AlCl3) produces methyl-2,4-dimethoxysalicylate (8) in good yield, instead of the expected 2,4,6-trimethoxybenzoic acid. The X-ray structure of 8 shows intramolecular hydrogen bonds between the carbonyl oxygen and hydrogens of Me and OH groups. A measured pKa value of 6.8 compares well with a value of 6.4 estimated using the [C=O···H···O] hydrogen bond distances.Key words: anti–tumor, novel synthesis, X-ray structure, hydrogen bonds, computational analysis.

Crystal and molecular structure of the di-μ-hydroxo-dimolybdenum compound, [Mo(CO)2(OH)(C4H7)(3,5-diMepzH)]2•C6H6

1988 ◽  
Vol 66 (1) ◽  
pp. 97-100 ◽  
Author(s):  
Steven J. Rettig ◽  
Alan Storr ◽  
James Trotter
Keyword(s):  
Hydrogen Bonds ◽  
Crystal And Molecular Structure ◽  
Dimeric Molecule ◽  
Oh Groups ◽  
Fourier Methods ◽  
Full Matrix ◽  
X Ray ◽  
Benzene Solvate ◽  
Intramolecular Hydrogen ◽  
Pyrazole Ligands

The synthesis and X-ray crystal analysis of a hydroxy-bridged molybdenum dimer are described. Crystals of di-μ-hydroxo-bis [dicarbonyl(3,5-dimethylpyrazole)(η3-2-methylallyl)molybdenum(II)] benzene solvate are monoclinic, P21/c, a = 7.508(1), b = 20.747(1), c = 20.717(3) Å, β = 99.536(6)°, Z = 4. The structure was determined by Patterson and Fourier methods and refined by full-matrix least-squares procedures to R = 0.022 for 3197 observed reflections. The dimeric molecule contains two distorted Mo coordination octahedra sharing an OH … OH edge to form a central folded four-membered Mo(μ-OH)2Mo ring. The pyrazole ligands form bent N—H … O intramolecular hydrogen bonds to the bridging OH groups, and the other ligands occupy positions which result in approximate C2 molecular symmetry. Two sets of Mo—OH bonds differ significantly in length, 2.237(2) and 2.140(2) Å; other molecular dimensions are within expected ranges. Molecules are linked into chains along a by O—H … OC hydrogen bonds, and benzene solvate molecules are well defined.

scholarly journals Novel One-Pot Synthesis of Methyl 4-Hydroxy-2-thioxo-1,2-dihydroquinoline-3-carboxylate: Synthetic and Crystallographic Studies

Molbank ◽  
10.3390/m1085 ◽  
2019 ◽  
Vol 2019 (4) ◽  
pp. M1085 ◽  
Author(s):  
Kovalenko ◽  
Drushlyak ◽  
Konovalova ◽  
Mariutsa ◽  
Kravchenko ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Ester Group ◽  
Carbonyl Oxygen ◽  
X Ray Diffraction ◽  
Intermolecular Hydrogen Bonds ◽  
One Pot ◽  
X Ray ◽  
Methyl Malonate ◽  
Intramolecular Hydrogen ◽  
Strong Intramolecular Hydrogen Bond

A new suitable method of synthesis of methyl 4-hydroxy-2-thioxo-1,2-dihydroquinoline-3-carboxylate by condensation of methyl 2-isothiocyanatobenzoate and methyl malonate is described. The structure of the compound both and by-product methyl 2(methoxycarbonothioylamino)benzoate was confirmed by means of elemental analysis, 1H NMR, 13C NMR, LC/MS and single crystal X-ray diffraction. UV/Vis and IR spectra of compounds are described. The presence of a strong intramolecular hydrogen bond between the hydroxy group and the carbonyl oxygen atom of the ester group in methyl 4-hydroxy-2-thioxo-1,2-dihydroquinoline-3-carboxylate is shown. The crystal structure of product was stabilized through intermolecular hydrogen bonds.

scholarly journals Crystal structure of atazanavir, C38H52N6O7

2020 ◽  
Vol 35 (2) ◽  
pp. 129-135
Author(s):  
James A. Kaduk ◽  
Amy M. Gindhart ◽  
Thomas N. Blanton
Keyword(s):  
Crystal Structure ◽  
Hydrogen Bonds ◽  
Powder Diffraction ◽  
Density Functional ◽  
Carbonyl Oxygen ◽  
Hydroxyl Group ◽  
Amide Nitrogen ◽  
Classical Hydrogen Bond ◽  
Intramolecular Hydrogen ◽  
Atazanavir Sulfate

The crystal structure of atazanavir has been solved and refined using synchrotron X-ray powder diffraction data and optimized using density functional techniques. Atazanavir crystallizes in space group P21 (#4) with a = 15.33545(7), b = 5.90396(3), c = 21.56949(13) Å, β = 96.2923(4)°, V = 1941.134(11) Å3, and Z = 2. Despite being labeled as “atazanavir sulfate”, the commercial reagent sample consisted of atazanavir free base. The structure consists of an array of extended-conformation molecules parallel to the ac-plane. Although the atazanavir molecule contains only four classical hydrogen bond donors, hydrogen bonding is, surprisingly, important to the crystal energy. Both intra- and intermolecular hydrogen bonds are significant. The hydroxyl group forms bifurcated intramolecular hydrogen bonds to a carbonyl oxygen atom and an amide nitrogen. Several amide nitrogens act as donors to the hydroxyl group and carbonyl oxygen atoms. An amide nitrogen acts as a donor to another amide nitrogen. Several methyl, methylene, methyne, and phenyl hydrogens participate in hydrogen bonds to carbonyl oxygens, an amide nitrogen, and the pyridine nitrogen. The powder pattern is included in the Powder Diffraction File™ as entry 00-065-1426.

3,3′-N,N′-Bis(amino)-2,2′-bipyridine — An unusually methylation-resistant amine

2011 ◽  
Vol 89 (8) ◽  
pp. 971-977
Author(s):  
Danielle M. Chisholm ◽  
Robert McDonald ◽  
J. Scott McIndoe
Keyword(s):  
Crystal Structure ◽  
Hydrogen Bonds ◽  
Complex Mixtures ◽  
Amino Groups ◽  
Intramolecular Hydrogen Bonds ◽  
X Ray ◽  
Intramolecular Hydrogen

Methylation of aromatic amino groups is usually straightforward, but the formation of two intramolecular hydrogen bonds in 3,3′-N,N′-bis(amino)-2,2′-bipyridine and (or) the potential for ring methylation prevents the clean tetramethylation of this molecule. Numerous attempts to make 3,3′-N,N′-bis(dimethylamino)-2,2′-bipyridine produced only complex mixtures of variously methylated products, and the only isolated molecule was 3,3′-N,N′-bis(methylamino)-2,2′-bipyridine, for which an X-ray crystal structure was obtained.

Synthesis and Structural Characterisation of New Bifunctional o-Hydroxyacetophenones – Potential Linker Molecules for Coordinative Framework Construction

2013 ◽  
Vol 68 (3) ◽  
pp. 214-222 ◽  
Author(s):  
Jörg Hübscher ◽  
Michael Günthel ◽  
Robert Rosin ◽  
Wilhelm Seichter ◽  
Florian Mertens ◽  
...  
Keyword(s):  
Hydrogen Bond ◽  
Hydrogen Bonds ◽  
X Ray ◽  
Structural Characterisation ◽  
Crystallographic Study ◽  
Copper Coordination ◽  
Resonance Assisted Hydrogen Bond ◽  
Intramolecular Hydrogen ◽  
Fitting In ◽  
Linker Molecules

Two new linker-type molecules 1a and 1b composed of o-hydroxyacetophenone coordinative groups attached to linear ethynylene or 1,4-phenylenediethynylene spacer units have been synthesised and structurally characterised. An X-ray crystallographic study for both compounds has shown structures with strong intramolecular hydrogen bonds fitting in the model of ‘Intramolecular Resonance Assisted Hydrogen Bond (IRHAB)’. Initial coordination experiments with Cu(II) were performed and the resulting materials characterised by PXRD. The similarity of the copper coordination between these compounds and copper(II) acetylacetonate complexes was demonstrated by XPS measurements. Based on the evidence of these studies, and on elemental analysis, the formation of the corresponding coordination polymers comprising Cu(II) and the linkers has been proposed

Distinguishment of Weak Interactions of Hydrogen Atoms Bound to Carbon Atoms: X-Ray Crystal Structural and Hirshfeld Surface Analyses of 2-Hydroxy-7-methoxy-3-(2,4,6-trimethylbenzoyl)naphthalene with the 2-Methoxylated Homologue

2021 ◽  
Vol 19 ◽  
Author(s):  
Kikuko Iida ◽  
Toyokazu Muto ◽  
Miyuki Kobayashi ◽  
Hiroaki Iitsuka ◽  
Kun Li ◽  
...  
Keyword(s):  
Hydrogen Bonds ◽  
Title Compound ◽  
Molecular Conformation ◽  
Weak Interactions ◽  
Carbonyl Oxygen ◽  
Hirshfeld Surface ◽  
Molecular Surface ◽  
Hydrogen Atoms ◽  
X Ray ◽  
Classical Hydrogen Bond

Abstract: X-ray crystal and Hirshfeld surface analyses of 2-hydroxy-7-methoxy-3-(2,4,6-trimethylbenzoyl)naphthalene and its 2-methoxylated homologue show quantitatively and visually distinct molecular contacts in crystals and minute differences in the weak intermolecular interactions. The title compound has a helical tubular packing, where molecules are piled in a two-folded head-to-tail fashion. The homologue has a tight zigzag molecular string lined up behind each other via nonclassical intermolecular hydrogen bonds between the carbonyl oxygen atom and the hydrogen atom of the naphthalene ring. The dnorm index obtained from the Hirshfeld surface analysis quantitatively demonstrates stronger molecular contacts in the homologue, an ethereal compound, than in the title compound, an alcohol, which is consistent with the higher melting temperature of the former than the latter. Stabilization through the significantly weak intermolecular nonclassical hydrogen bonding interactions in the homologue surpasses the stability imparted by the intramolecular C=O…H–O classical hydrogen bonds in the title compound. The classical hydrogen bond places the six-membered ring in the concave of the title molecule. The hydroxy group opposingly disturbs the molecular aggregation of the title compound, as demonstrated by the distorted H…H interactions covering the molecular surface, owing to the rigid molecular conformation. The position of effective interactions predominate over the strength of the classical/nonclassical hydrogen bonds in the two compounds.

scholarly journals One-pot synthesis of (1RS,21SR)-diethyl 2-[23-amino-22-ethoxycarbonyl-8,11,14-trioxa-25-azatetracyclo[19.3.1.02,7.015,20]pentacosa-2,4,6,15(20),16,18,22-heptaen-25-yl]but-2-endioate

2018 ◽  
Vol 74 (9) ◽  
pp. 1281-1284
Author(s):  
Thi Thanh Van Tran ◽  
Tuan Anh Le ◽  
Hong Hieu Truong ◽  
Thi Nhung Dao ◽  
Anatoly T. Soldatenkov ◽  
...  
Keyword(s):  
Hydrogen Bonds ◽  
Molecular Conformation ◽  
Michael Reaction ◽  
Biological Activities ◽  
Boat Conformation ◽  
One Pot ◽  
Computer Prediction ◽  
Compound C ◽  
Intramolecular Hydrogen ◽  
The Michael Reaction

The title compound, C30H34N2O9 (4), is a product of the Michael reaction of azacrown ether with dimethyl acetylenedicarboxylate modified by an addition of NH3 (aq.) at 298 K. The aza-14-crown-4-ether ring adopts a bowl conformation. The dihedral angle between the planes of the benzene rings fused to the aza-14-crown-4-ether moiety is 8.65 (5)°. The tetrahydropyridine ring has a boat conformation. The molecular conformation is supported by one N—H...O and two C—H...O intramolecular hydrogen bonds. Both heterocyclic and amino N atoms have essentially planar configurations (sums of the bond angles are 359.35 and 358.00°). Compound 4 crystallizes as a racemate consisting of enantiomeric pairs of the 1R,21S diastereomer. In the crystal, molecules of 4 are connected by N—H...O hydrogen bonds, forming chains along [100]. According to the PASS program (computer prediction of biological activities), compound 4 may exhibit antiallergic (72% probability) and antiasthmatic (67%) activity, as well as be a membrane permeability inhibitor (65%).

scholarly journals The Importance of CH···X (X = O, π) Interaction of a New Mixed Ligand Cu(II) Coordination Polymer: Structure, Hirshfeld Surface and Theoretical Studies

Crystals ◽  
2018 ◽  
Vol 8 (12) ◽  
pp. 455 ◽  
Author(s):  
Saikat Seth
Keyword(s):  
Solid State ◽  
Hydrogen Bonds ◽  
Noncovalent Interactions ◽  
Carbonyl Oxygen ◽  
Hirshfeld Surface ◽  
Mixed Ligand ◽  
Binding Energies ◽  
Zigzag Chain ◽  
X Ray ◽  
Π Interactions

In this study, a new equimolar (1:1:1) mixed ligand Cu(II) polymer, [Cu(IDA)(ImP)]n (1) with iminodiacetato (IDA) and imidazo[1,2-a]-pyridine (ImP) was synthesized and characterized by single crystal X-ray diffraction analysis. X-ray crystallography reveals that compound (1) consists of polymeric zigzag chain along [010] the carboxylate carbonyl oxygen atom by two-fold symmetry screw axis. The solid-state structure is stabilized through C–H···O hydrogen bonds and C–H···π interactions that lead the molecules to generate two-dimensional supramolecular assemblies. The intricate combinations of hydrogen bonds and C–H···π interactions are fully described along with computational studies. A thorough analysis of Hirshfeld surface and fingerprint plots elegantly quantify the interactions involved within the structure. The binding energies associated with the noncovalent interactions observed in the crystal structure and the interplay between them were calculated using theoretical DFT calculations. Weak noncovalent interactions were analyzed and characterized using Bader’s theory of ‘‘atoms-in-molecules’’ (AIM). Finally, the solid-state supramolecular assembly was characterized by the “Noncovalent Interaction” (NCI) plot index.

scholarly journals Magnetic γFe2O3@Sh@Cu2O: an efficient solid-phase catalyst for reducing agent and base-free click synthesis of 1,4-disubstituted-1,2,3-triazoles

BMC Chemistry ◽  
2020 ◽  
Vol 14 (1) ◽  
Author(s):  
Fereshteh Norouzi ◽  
Shahrzad Javanshir
Keyword(s):  
Photoelectron Spectroscopy ◽  
Inductively Coupled Plasma ◽  
Solid Phase ◽  
Click Reaction ◽  
Copper Acetate ◽  
Reducing Agent ◽  
Gravimetric Analysis ◽  
High Turnover ◽  
One Pot ◽  
X Ray

AbstractA hybrid magnetic material γFe2O3@Sh@cu2O was easily prepared from Shilajit (Sh) decorated Fe3O4 and copper acetate. The prepared magnetic hybrid material was fully characterized using different analysis, including Fourier transform infrared (FT-IR), X-ray diffraction (XRD), inductively coupled plasma (ICP), scanning electron microscopy (SEM), Energy-dispersive X-ray spectroscopy (EDX), X-ray photoelectron spectroscopy (XPS), vibrating sample magnetometer (VSM) thermal gravimetric analysis (TGA) and Brunauer–Emmett–Teller (BET). All these analysis revealed that during coating of Fe3O4@Sh using copper salt (II), synchronized redox sorption of CuII to CuI occurs at the same time as the oxidation of Fe3O4 to γFe2O3. This magnetic catalyst exhibited excellent catalytic activity for regioselective synthesis of 1,4-disubstituted-1,2,3-triazoles via one pot three-component click reaction of sodium azide, terminal alkynes and benzyl halides in the absence of any reducing agent. High yields, short reaction time, high turnover number and frequency (TON = 3.5 * 105 and TOF = 1.0 * 106 h−1 respectively), easy separation, and efficient recycling of the catalyst are the strengths of the present method.

Bio-adsorbent derived from papaya peel waste and magnetic nanoparticles fabricated for lead determination

2018 ◽  
Vol 90 (1) ◽  
pp. 79-92 ◽  
Author(s):  
Sahar Abbaszadeh ◽  
Hamid Rashidi Nodeh ◽  
Sharifah Rafidah Wan Alwi
Keyword(s):  
Waste Water ◽  
Magnetic Nanoparticles ◽  
Solid Phase ◽  
Tap Water ◽  
Lead Ions ◽  
Coefficient Of Determination ◽  
One Pot ◽  
X Ray ◽  
Lead Determination ◽  
Flame Atomic Absorption

AbstractDetermination of toxic lead ions at trace level using solid-based adsorbents has become of interest in recent years. In this work, a novel bio-adsorbent originating from papaya peel waste (PPw) and magnetic nanoparticles (Fe3O4) was developed (Fe3O4/PPw). The new adsorbent was prepared using a one-pot green method and characterized by Fourier transform infrared, X-ray diffractometer, energy-dispersive X-ray spectroscopy and field emission scanning electron microscopy. The synthesized Fe3O4/PPw was used as a magnetic solid-phase extraction (MSPE) sorbent for extraction of lead ions from waste water prior to assessing by flame atomic absorption spectroscopy. The parameters influencing extraction recovery, including desorption solvent, solvent volume, sample volume, extraction time, desorption time, adsorbent dosage, salt effect and pH were optimized. A linear response for the MSPE method was achieved at concentrations from 10 to 100 ng mL−1 with a good coefficient of determination (R2=0.9987). Detection limits and quantitation limit of the MSPE method were observed around 2 ng mL−1 and 6.6 ng mL−1, respectively. The intraday and interday precision (%RSD) was in the range 1.6%–4.5% and 2.3%–7.4%, respectively. The recovery amounts obtained were 91% for tap water, 85.9% for river water and 86% for waste water. The synthesized adsorbent showed a minimum reusability of eight cycles without significant change in the lead determination. The results proved that the new bio-adsorbent (Fe3O4/PPw) is potentially capable to extract the Pb(II) from aqueous media under optimum conditions with a high extraction efficiency.

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