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1.
Acta Crystallogr E Crystallogr Commun ; 80(Pt 2): 201-206, 2024 Feb 01.
Article in English | MEDLINE | ID: mdl-38333113

ABSTRACT

In the title benzyl-ideneaniline Schiff base, C18H22N2O, the aromatic rings are inclined to each other by 46.01 (6)°, while the Car-N= C-Car torsion angle is 176.9 (1)°. In the crystal, the only identifiable directional inter-action is a weak C-H⋯π hydrogen bond, which generates inversion dimers that stack along the a-axis direction.

2.
Acta Crystallogr E Crystallogr Commun ; 79(Pt 6): 538-544, 2023 May 01.
Article in English | MEDLINE | ID: mdl-37288464

ABSTRACT

The title Schiff base compounds, C22H26N4O (I) and C18H16FN3O (II), were each synthesized by a single-step condensation reaction. The substituted benzyl-idene ring is inclined to the pyrazole ring mean planes by 22.92 (7)° in I and 12.70 (9)° in II. The phenyl ring of the 4-amino-anti-pyrine unit is inclined to the pyrazole ring mean plane by 54.87 (7)° in I and by 60.44 (8)° in II. In the crystal of I, the mol-ecules are linked by C-H⋯O hydrogen bonds and C-H⋯π inter-actions to form layers lying parallel to (001). In the crystal of II, the mol-ecules are linked by C-H⋯O and C-H⋯F hydrogen bonds and C-H⋯π inter-actions, thereby forming layers lying parallel to (010). Hirshfeld surface analysis was employed to further qu-antify the inter-atomic inter-actions in the crystals of both compounds.

3.
Acta Crystallogr E Crystallogr Commun ; 79(Pt 3): 146-150, 2023 Feb 01.
Article in English | MEDLINE | ID: mdl-36909996

ABSTRACT

The crystal structure of the title compound, C13H9Br2N [systematic name: (E)-N,1-bis-(4-bromo-phen-yl)methanimine], is a second polymorph (Form II) crystallizing in the ortho-rhom-bic space group Pccn. The first polymorph (Form I) crystallizes in the monoclinic space group P21/c [Bernstein & Izak (1975 ▸). J. Cryst. Mol. Struct. 5, 257-266; Marin et al. (2013 ▸). J. Mol. Struct. 1049, 377-385]. The mol-ecule is disordered about an inversion center situated in the middle of the C=N bond, similar to the situation in the monoclinic polymorph: the C=N bond length is 1.243 (7) Å. In the crystal, mol-ecules stack along the b-axis direction and are linked by C-H⋯π inter-actions. The inter-atomic contacts in the crystal for both polymorphs were studied by Hirshfeld surface analysis and have notable differences. The solid-state fluorescence spectrum of Form II shows an emission peak at ca 469 nm. The two-photon absorption coefficient measured from the open aperture Z-scan technique is 1.3 × 10 -11 m W-1, hence, Form II shows optical limiting behaviour.

4.
Article in English | MEDLINE | ID: mdl-25942090

ABSTRACT

The structure of (E)-1-(4-Bromophenyl)-3-(napthalen-2-yl)prop-2-en-1-one (C19H13BrO) crystallized in the triclinic system of P-1 space group. The unit cell dimensions are: a=5.8944 (9)Å, b=7.8190 (12)Å, c=16.320 (2)Å, α=102.4364 (19)°, ß=95.943 (2)°, γ=96.274 (2)° and Z=2. The physical properties of this compound was determined by the spectroscopic methods (FTIR and (1)H and (13)C NMR). Quantum chemical investigations have been employed to investigate the structural and spectral properties. The molecular structure, vibrational assignments, (1)H and (13)C NMR chemical shift values, non-linear optical (NLO) effect, HOMO-LUMO analysis and natural bonding orbital (NBO) analysis were calculated using HF and DFT/B3LYP methods with 6-311++G(d,p) basis set in the ground state. The results show that the theoretical calculation of the geometrical parameters, vibrational frequencies and chemical shifts are comparable with the experimental data. The crystal structure is influenced and stabilized by weak C-H⋯π interactions connecting the molecules into infinite supramolecular one dimensional ladder-like arrangement. Additionally, this compound is evaluated for their antibacterial activities against gram positive and gram negative strains using a micro dilution procedure and shows activities against a panel of microorganisms.


Subject(s)
Chalcone/chemical synthesis , Chalcone/pharmacology , Chalcones/chemical synthesis , Chalcones/pharmacology , Models, Molecular , Naphthalenes/chemical synthesis , Naphthalenes/pharmacology , Quantum Theory , Antioxidants/pharmacology , Bacteria/drug effects , Carbon Isotopes , Chalcone/chemistry , Chalcones/chemistry , Crystallography, X-Ray , Hardness , Hydrogen , Hydrogen Bonding , Microbial Sensitivity Tests , Molecular Conformation , Monophenol Monooxygenase/antagonists & inhibitors , Naphthalenes/chemistry , Nonlinear Dynamics , Optical Phenomena , Spectroscopy, Fourier Transform Infrared , Thermodynamics , Vibration , Yeasts/drug effects
5.
Spectrochim Acta A Mol Biomol Spectrosc ; 144: 215-25, 2015 Jun 05.
Article in English | MEDLINE | ID: mdl-25756689

ABSTRACT

The FT-IR, FT-Raman, (1)H, (13)C NMR and UV-Visible spectral measurements of N'-hydroxy-pyrimidine-2-carboximidamide (HPCI) and complete analysis of the observed spectra have been proposed. DFT calculation has been performed and the structural parameters of the compound was determined from the optimized geometry with 6-311+G(d,p) basis set and giving energies, harmonic vibrational frequencies and force constants. The results of the optimized molecular structure are presented and compared with the experimental. The geometric parameters, harmonic vibrational frequencies and chemical shifts were compared with the experimental data of the molecule. The title compound, C5H6N4O, is approximately planar, with an angle of 11.04 (15)°. The crystal structure is also stabilized by intermolecular N-H⋯O, N-H⋯N, O-H⋯N, C-H⋯O hydrogen bond and offset π-π stacking interactions. The influences of hydroxy and carboximidamide groups on the skeletal modes and proton chemical shifts have been investigated. Moreover, we have not only simulated highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) but also determined the transition state and band gap. The kinetic, thermodynamic stability and chemical hardness of the molecule have been determined. Complete NBO analysis was also carried out to find out the intermolecular electronic interactions and their stabilization energy. The thermodynamic properties like entropies and their correlations with temperatures were also obtained from the harmonic frequencies of the optimized structure.


Subject(s)
Amidines/chemistry , Electrons , Models, Molecular , Pyrimidines/chemistry , Quantum Theory , Vibration , Carbon-13 Magnetic Resonance Spectroscopy , Entropy , Molecular Conformation , Proton Magnetic Resonance Spectroscopy , Spectroscopy, Fourier Transform Infrared , Thermodynamics
6.
Spectrochim Acta A Mol Biomol Spectrosc ; 135: 307-16, 2015 Jan 25.
Article in English | MEDLINE | ID: mdl-25084236

ABSTRACT

The molecular structure of a new Schiff base, 2-[4-hydroxy benzylidene]-amino naphthalene (HBAN) has been examined by HF and B3LYP/6-311++G(d,p) calculations. The X-ray structure was determined in order to establish the conformation of the molecule. The compound, C17H13NO, crystallizes in the orthorhombic, P212121 space group with the cell dimension, a=6.2867(2), b=10.2108(3), c=19.2950(6) Å, α=ß=γ=90° and z=4. The asymmetric unit contains a molecule of a Schiff base. A strong intermolecular O-H⋯N and a weak C-H⋯O hydrogen bonds stabilized the crystal structure. The vibrational spectra of HBAN have been calculated using density functional theoretical computation and compared with the experimental. The study is extended to the HOMO-LUMO analysis to calculate the energy gap (Δ), Ionization potential (I), Electron Affinity (A), Global Hardness (η), Chemical Potential (µ) and Global Electrophilicity (w). The calculated HOMO and LUMO energy reveals that the charge transfer occurs within the molecule.


Subject(s)
Benzylidene Compounds/chemistry , Benzylidene Compounds/chemical synthesis , Models, Molecular , Naphthalenes/chemistry , Naphthalenes/chemical synthesis , Schiff Bases/chemistry , Schiff Bases/chemical synthesis , Crystallography, X-Ray , Hydrogen Bonding , Ligands , Molecular Conformation , Spectroscopy, Fourier Transform Infrared , Spectrum Analysis, Raman , Thermodynamics , Vibration
7.
Spectrochim Acta A Mol Biomol Spectrosc ; 131: 647-56, 2014 Oct 15.
Article in English | MEDLINE | ID: mdl-24915766

ABSTRACT

The FT-IR and FT-Raman spectra of 4-chloro-2-nitroanisole were recorded and analyzed. The vibrational wavenumbers were examined theoretically with the aid of the GAUSSIAN 09 package of programs using the B3LYP/6-311G(d,p) and 6-311++G(d,p) levels of theory. The data obtained from vibrational wavenumber calculations are used to assign vibrational bands obtained in IR and Raman spectroscopy of the studied molecule. The first hyperpolarizability, NBO, HOMO-LUMO, NMR, UV, infrared intensities and Raman intensities are reported. The calculated first hyperpolarizability is comparable with the reported values of similar derivatives and is an attractive object for future studies of non-linear optics. The geometrical parameters of the title compound are in good agreement with the values of similar structures.


Subject(s)
Anisoles/chemistry , Thermodynamics , Halogenation , Molecular Conformation , Quantum Theory , Spectroscopy, Fourier Transform Infrared , Spectrum Analysis, Raman
8.
Med J Malaysia ; 69(1): 35-6, 2014 Feb.
Article in English | MEDLINE | ID: mdl-24814628

ABSTRACT

Haemangioma can be present in the lung but rarely causes complications unless there is a bleed. Ghon's focus is a result of post primary tuberculosis. It is a caseating granuloma which invades the surrounding tissue. It is usually benign and may resolve spontaneously without causing complications or active tuberculosis. This case illustrates an unfortunate patient who had a pre-existing haemangioma in the lung which was in close proximity of a Ghon's focus that had invaded on to the haemangioma leading to haemorrhage causing death. This study seeks to highlight the importance of conducting a full post mortem in cases of maternal mortality.

10.
Article in English | MEDLINE | ID: mdl-23274374

ABSTRACT

One of the Schiff base 4-bromo-4'dimethylamino benzylideneaniline (BDMABA) compounds was synthesized and single crystal of the material was grown by solvent evaporation method at room temperature. Molecular structure of BDMABA was confirmed by (1)H nuclear magnetic resonance and the presence of functional groups was confirmed by Fourier Transform Infrared and Fourier Transform Raman spectral analyses. Cell parameters were determined using single crystal X-ray diffraction analysis and crystalline perfection of the grown BDMABA crystal was evaluated using high-resolution X-ray diffraction analysis. Thermal analyses indicated that the material is thermally stable up to 215 °C and its melting point is 161.5 °C. Vickers microhardness study was carried out to estimate the mechanical hardness of BDMABA crystal which shows that the crystal belongs to the class of soft materials. Linear and nonlinear optical studies were carried out using UV-vis-NIR spectrum and open aperture Z-scan technique respectively.


Subject(s)
Aniline Compounds/chemistry , Aniline Compounds/chemical synthesis , Methylamines/chemistry , Methylamines/chemical synthesis , Photons , Absorption , Crystallization , Differential Thermal Analysis , Magnetic Resonance Spectroscopy , Mechanical Phenomena , Powders , Spectroscopy, Fourier Transform Infrared , Spectrum Analysis, Raman , Temperature , Thermogravimetry , X-Ray Diffraction
11.
Article in English | MEDLINE | ID: mdl-22885085

ABSTRACT

Single crystal of an organic material, 4-chloro-4'bromobenzylidene aniline (CBBA), was synthesized and grown by slow evaporation method at room temperature. (1)H and (13)C NMR spectra were recorded to elucidate the molecular structure and functional groups of CBBA were identified using FTIR and FT Raman spectral analyses. The lattice parameters were calculated from single crystal X-ray diffraction data. Single and reasonably sharp peak observed in the high resolution X-ray diffraction curve indicates that the quality of the crystal is good. Thermal properties of CBBA were carried out using thermogravimetric, differential thermal and differential scanning calorimetric analyses and the melting point of the CBBA material is ~123 °C. The dielectric properties of CBBA crystal was studied as the function of frequency (100 Hz-500 kHz). The optical properties were ascertained by recording UV-vis-NIR and fluorescence spectrum. Further the mechanical properties were studied using Vickers microhardness test.


Subject(s)
Aniline Compounds/chemistry , Schiff Bases/chemistry , Crystallization , Differential Thermal Analysis , Electricity , Magnetic Resonance Spectroscopy , Optical Phenomena , Powders , Spectrometry, Fluorescence , Spectrophotometry, Ultraviolet , Spectroscopy, Fourier Transform Infrared , Spectrum Analysis, Raman , Temperature , Thermogravimetry , Vibration , X-Ray Diffraction
12.
Acta Crystallogr Sect E Struct Rep Online ; 68(Pt 3): m335-6, 2012 Mar 01.
Article in English | MEDLINE | ID: mdl-22412468

ABSTRACT

In the title compound, {(NH(4))[Cd(NCS)(3)]·C(12)H(24)O(6)}(n), the Cd(2+) ion, the ammonium cation, one of the SCN(-) ligands and the macrocycle are located on mirror planes. The thiocyanate anions act as bridging ligands between the Cd(II) ions, leading to a polymeric chain arrangement extending along [001] around a twofold screw axis. The ammonium ions are contained within the bowl of the macrocycle via extensive N-H⋯O hydrogen bonding.

13.
Malays Fam Physician ; 7(2-3): 31-4, 2012.
Article in English | MEDLINE | ID: mdl-25606253

ABSTRACT

58 cases of sputum smear negative pulmonary tuberculosis (PTB) were reported to Kinta Health Department between January and June 2011. It was found that 47 cases (81%) were sputum smear negative cases. Six cases (10.3%) were actually sputum smear positive but were wrongly reported as smear negative. Five cases (8.6%) were misdiagnosed as tuberculosis. Majority of these patients (82.7%) sought consultation and treatment after two weeks of having cough. Only 6.9% sought treatment for cough that was less than two weeks old. Accurate diagnosis of PTB is crucial and the Perak State Health Department needs to quickly adopt steps to improve the situation.

14.
Article in English | MEDLINE | ID: mdl-21802980

ABSTRACT

The organic material 4-chloro-4'-chlorobenzylidene aniline (CCBA) was synthesized and confirmed by NMR and FTIR spectral analyses. CCBA crystal was grown from chloroform by slow evaporation at room temperature and the single crystal cell parameters were determined by single crystal X-ray diffraction method. The perfection of the grown crystal was analyzed by high resolution X-ray diffraction rocking curve analysis. Fluorescence spectrum indicated violet emission at 428 nm. The range of optical absorbance was ascertained by recording UV-vis-NIR spectrum. Load dependant microhardness measurements on this crystal revealed the mechanical behavior of the material. Stiffness constant, Meyer index and yield strength of CCBA crystal were calculated. Dielectric studies were carried out to estimate the dielectric parameters of the grown crystal in the frequency range from 100 Hz to 100 kHz. The thermal behavior of CCBA was investigated using differential scanning calorimetry (DSC) and no phase transition was identified in the temperature region 30-100°C. Further, the CCBA crystal was subjected to open aperture Z-scan studies in order to investigate the third order nonlinear optical (NLO) properties of CCBA crystal.


Subject(s)
Aniline Compounds/chemistry , Aniline Compounds/chemical synthesis , Benzaldehydes/chemistry , Calorimetry, Differential Scanning/methods , Spectrophotometry, Ultraviolet/methods , Spectroscopy, Fourier Transform Infrared/methods , Spectroscopy, Near-Infrared/methods , Crystallization , Hot Temperature , Magnetic Resonance Spectroscopy/methods , Models, Chemical , Spectrometry, Fluorescence/methods , Temperature , X-Ray Diffraction
15.
Spectrochim Acta A Mol Biomol Spectrosc ; 79(5): 1747-56, 2011 Sep.
Article in English | MEDLINE | ID: mdl-21680229

ABSTRACT

The FT-IR and FT-Raman spectra of 2-bromo-4-chlorotoluene (2B4CT) molecule have been recorded in the region 4000-400 cm(-1) and 3500-50 cm(-1), respectively. Optimized geometrical structures, harmonic vibrational frequencies, intensities, reduced mass, force constants and depolarization ratio have been computed by the B3 based (B3LYP) density functional methods using 6-31+G(d,p) and 6-311++G(d,p) basis sets. The observed FT-IR and FT-Raman vibrational frequencies are analysed and compared with theoretically predicted vibrational frequencies. The geometries and normal modes of vibration obtained from DFT method are in good agreement with the experimental data. The Mulliken charges, the natural bonding orbital (NBO) analysis, the values of electric dipole moment (µ) and the first-order hyperpolarizability (ß) of the investigated molecule were computed using DFT calculations. The calculated HOMO and LUMO energies show that charge transfer occurs within molecule. The influences of bromine atom, chlorine atom and methyl group on the geometry of benzene and its normal modes of vibrations have also been discussed.


Subject(s)
Quantum Theory , Spectroscopy, Fourier Transform Infrared , Spectrum Analysis, Raman , Toluene/analogs & derivatives , Models, Molecular , Molecular Structure , Spectrophotometry, Ultraviolet , Toluene/chemistry , Vibration
16.
Article in English | MEDLINE | ID: mdl-21242098

ABSTRACT

The organic nonlinear optical material of 4-bromo-4'chloro benzylidene aniline (BCBA) was synthesized and single crystal of BCBA was grown from acetone solution by solvent evaporation method at room temperature. Its three dimensional structure was elucidated from single crystal X-ray diffraction analysis at 173 K. Synthesized compound of BCBA was subjected to FTIR and (1)H and (13)C NMR spectral analyses. The range and percentage of optical transmission of BCBA was determined by UV-vis-NIR spectrum and its fluorescence spectrum was recorded using spectrofluorometer. The mechanical strength of the crystal was estimated using Vickers microhardness test on the (001) plane. Dielectric constant of the grown crystal was measured for various frequencies along (001) plane. The third order nonlinear optical properties of BCBA were investigated by Z-scan technique with He-Ne laser radiation of wavelength at 632.8 nm and the corresponding nonlinear refractive index, absorption coefficient and optical susceptibility were calculated.


Subject(s)
Aniline Compounds/chemistry , Aniline Compounds/chemical synthesis , Benzylidene Compounds/chemistry , Benzylidene Compounds/chemical synthesis , Crystallization , Materials Testing , Molecular Structure , Nuclear Magnetic Resonance, Biomolecular , Optics and Photonics , Spectroscopy, Fourier Transform Infrared , X-Ray Diffraction
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