Augmenting the effect of solvents on optical nonlinearity by spectroscopic, DFT, solvatochromism and z-scan studies of push-pull chalcone: (2E)-1-(4-ethoxyphenyl)-3-(4-methoxyphenyl)prop-2-en-1-one.

In this article, the structural and nonlinear optical behaviour of a chalcone derivative, (2E)-1-(4-ethoxyphenyl)-3-(4-methoxyphenyl)prop-2-en-1-one have been studied. FT-IR, FT-Raman, and NMR spectroscopy were analyzed to validate the molecular structure. To predict the nonlinear optical characteristics of the chalcone, the DFT approach was used and the experimental results were corroborated by the computations. The bathochromic shift is obtained in linear absorbance spectra and is validated using TD-DFT. Also, the broad emission in the blue region demonstrates the blue light emission property of the sample. Using the finite-field method, the dipole moments, polarizability, first-order and second-order hyperpolarizability parameters have been computed. Ground and excited state dipole moments were quantified by solvatochromism. The third-order nonlinear optical characteristics of chalcone in polar and non-polar solvent media were examined using the open/closed-aperture z-scan technique. The chalcone displayed considerable two-photon absorption with a positive nonlinear absorption coefficient and a positive index of refraction due to the self-focussing effect. Furthermore, the optical limiting study manifests that the investigated chalcone might well be favourable for NLO applications.

Enhanced NLO response and switching self-focussing in benzodiazepine derivative with -NO2 and -Br substitution.

Optoelectronic and the cubic nonlinear optical properties of 4-(4-Bromophenyl)-2-(4-nitrophenyl)-2, 3-dihydro-1H-1, 5-benzodiazepine have been studied. Z-scan technique was used for the third-order nonlinear optical measurements namely, nonlinear absorption, nonlinear refraction, and optical power limiting behaviour employing an Nd: YAG laser of 532 nm wavelength having 5 ns Gaussian pulses. B3LYP/6-311 ++ G (d, p) level of theory was employed for structural optimization, vibrational wavenumber, frontier molecular orbitals, natural bond orbital and population analysis. The MOLVIB programme was used to perform unambiguous vibrational assignments based on potential energy distribution values acquired from normal coordinate analysis. B3LYP and CAM-B3LYP hybrid functions have been employed at the DFT level to calculate the theoretical second-order hyperpolarizability. The substitution of -NO2 and -Br in this benzodiazepine compound enhances the second-order hyperpolarizability (γ) to the order of 10-34 esu and, switching of self-defocussing to self-focussing phenomenon. The HOMO-LUMO and optical band gap analysis illustrates that polarizing nature of the molecule vary with substituents. The obtained results indicate that this compound has potential applications in optoelectronics and photonics.

Inhibition of Ehrlich ascites cancer, hypoxia-inducible factor-1 alpha, and the kinase insert domain-containing receptor/fms-like tyrosine kinase-binding domains of vascular endothelial growth factor by Thiazole Acetamide Derivatives.

BACKGROUND: Tumor cells that have the ability to express vascular endothelial growth factor (VEGF) are more competent to growth and metastasize by the adequate amount of blood and oxygen supply by the blood vessels to the growing mass of cells. Hypoxic tumors are known for its aggressiveness and resistance to the treatment. Targeting VEGF and hypoxia-inducible factor-1 alpha (HIF-1α) is an attractive strategy to interrupt the multiple pathways crucial for tumor growth. In the present study, two thiazole acetamide derivative's anticancer property, anti VEGF and HIF-1α inhibitory property were investigated. METHODOLOGY: Two thiazole acetamide compounds were synthesized, TA1 and TA2 and its anticancer property was studied in Erlich's ascites cancer cells. To evaluate the anticancer property the assays such as 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay, DNA diffusion assay for apoptosis, and lactate dehydrogenase leakage assay were carried out. The cell culture media was used to assess the secreted VEGF level. Molecular docking studies were performed to analyze the binding efficiency of the study compounds to the kinase insert domain-containing receptor (KDR) and fms-like tyrosine kinase (FLT)-binding domains of VEGF protein. HIF-1α inhibitory study was performed by flow cytometry analysis using HUVEC cell line. RESULTS: The study compounds inhibited HIF-1α and VEGF secretion, these data shown positive prop up for the anticancer property of the derivatives. The docking studies showed moderate binding of study compounds to KDR and FLT-binding domains of VEGF protein. CONCLUSION: These results conclude the anticancer and anti-angiogenic property of the synthesized thiazole-acetamide derivatives.

FT-IR, HOMO-LUMO, NBO, MEP analysis and molecular docking study of 3-Methyl-4-{(E)-[4-(methylsulfanyl)-benzylidene]amino}1H-1,2,4-triazole-5(4H)-thione.

FT-IR spectrum of 3-Methyl-4-{(E)-[4-(methylsulfanyl)-benzylidene]amino}1H-1,2,4-triazole-5(4H)-thione was recorded and analysed. The vibrational wavenumbers were computed and at HF and DFT levels of theory. The data obtained from wavenumber calculations are used to assign the vibrational bands obtained in the IR spectrum. The NH stretching wavenumber is red shifted in the IR spectrum from the computed value, which indicates the weakening of the NH bond. The geometrical parameters of the title compound are in agreement with the XRD results. NBO analysis, HOMO-LUMO, first and second order hyperpolarizability and molecular electrostatic potential results are also reported. From the MEP map it is evident that the negative regions are localized over the sulphur atoms and N3 atom of triazole ring and the maximum positive region is localized on NH group, indicating a possible site for nucleophilic attack. Prediction of Activity Spectra analysis of the title compound predicts anti-tuberculostic activity with probability to be active value of 0.543. Molecular docking studies reveal that the triazole nitrogen atoms and the thione sulphur atom play vital role in bonding and results draw us to the conclusion that the compound might exhibit anti-tuberculostic activity.

Infrared spectrum, NBO, HOMO-LUMO, MEP and molecular docking studies (2E)-3-(3-nitrophenyl)-1-[4-piperidin-1-yl]prop-2-en-1-one.

FT-IR spectrum of (2E)-3-(3-nitrophenyl)-1-[4-piperidin-1-yl]prop-2-en-1-one was recorded and analyzed. The vibrational wavenumbers were computed using HF and DFT quantum chemical calculations. The data obtained from wavenumber calculations are used to assign IR bands. Potential energy distribution was done using GAR2PED software. The geometrical parameters of the title compound are in agreement with the XRD results. NBO analysis, HOMO-LUMO, first and second hyperpolarizability and molecular electrostatic potential results are also reported. The possible electrophile attacking sites of the title molecule is identified using MEP surface plot study. Molecular docking results predicted the anti-leishmanic activity for the compound.

FT-IR, NBO, HOMO-LUMO, MEP analysis and molecular docking study of Methyl N-({[2-(2-methoxyacetamido)-4-(phenylsulfanyl)phenyl]amino}[(methoxycarbonyl) imino]methyl)carbamate.

The optimized molecular structure, vibrational frequencies, corresponding vibrational assignments of Methyl N-({[2-(2-methoxyacetamido)-4-(phenylsulfanyl) phenyl]amino} [(methoxycarbonyl)imino]methyl)carbamate have been investigated using HF and DFT levels of calculations. The geometrical parameters are in agreement with XRD data. The stability of the molecule arising from hyper-conjugative interaction and charge delocalization has been analyzed using NBO analysis. The HOMO and LUMO analysis is used to determine the charge transfer within the molecule. Molecular electrostatic potential study was also performed. The first and second hyperpolarizability was calculated in order to find its role in nonlinear optics. Molecular docking studies are also reported. Prediction of Activity Spectra analysis of the title compound predicts anthelmintic and antiparasitic activity as the most probable activity with Pa (probability to be active) value of 0.808 and 0.797, respectively. Molecular docking studies show that both the phenyl groups and the carbonyl oxygens of the molecule are crucial for bonding and these results draw us to the conclusion that the compound might exhibit pteridine reductase inhibitory activity.

Molecular structure, FT-IR, NBO, HOMO and LUMO, MEP and first order hyperpolarizability of (2E)-1-(2,4-Dichlorophenyl)-3-(3,4,5-trimethoxyphenyl)prop-2-en-1-one by HF and density functional methods.

(2E)-1-(2,4-Dichlorophenyl)-3-(3,4,5-trimethoxyphenyl)prop-2-en-1-one is synthesized by using 2,4-dichloroacetophenone and 3,4,5-trimethoxybenzaldehyde in ethanol. The structure of the compound was confirmed by IR and single crystal X-ray diffraction studies. FT-IR spectrum of (2E)-1-(2,4-dichloro-phenyl)-3-(3,4,5-trimethoxyphenyl)prop-2-en-1-one was recorded and analyzed. The crystal structure is also described. The vibrational wavenumbers were computed using HF and DFT methods and are assigned with the help of potential energy distribution method. The first hyperpolarizability and infrared intensities are also reported. The geometrical parameters of the title compound obtained from XRD studies are in agreement with the calculated (DFT) values. The stability of the molecule arising from hyper-conjugative interaction and charge delocalization has been analyzed using NBO analysis. The HOMO and LUMO analysis are used to determine the charge transfer within the molecule. MEP was performed by the DFT method. From the MEP map of the title molecule, negative region is mainly localized over the electronegative oxygen atoms, in the carbonyl group and the oxygen atom O4 of the methoxy group and the maximum positive region is localized on the phenyl rings.

FT-IR, molecular structure, first order hyperpolarizability, NBO analysis, HOMO and LUMO and MEP analysis of 1-(10H-phenothiazin-2-yl)ethanone by HF and density functional methods.

FT-IR spectrum of 1-(10H-phenothiazin-2-yl)ethanone was recorded and analyzed. The equilibrium geometry, bonding features and harmonic vibrational wavenumbers were investigated with the help of HF and DFT methods. The normal modes are assigned with the help of potential energy distribution analysis. The observed vibrational wavenumbers were compared with the calculated results. The geometrical parameters of the title compound obtained from XRD studies are in agreement with the calculated (DFT) values. The first hyperpolarizability value is also reported. Natural bond orbital analysis confirms the presence of intra-molecular charge transfer and hydrogen bonding interaction. The HOMO-LUMO gap explains the charge transfer interaction taking place within the molecule. The N-H stretching frequency is red shifted in the IR spectrum with a strong intensity from the computed frequency, which indicates weakening of the N-H bond resulting in proton transfer to the neighboring units. From the MEP analysis it is evident that the negative charge covers the carbonyl and benzene and the positive region is over the NH group.

Molecular structure, FT-IR, vibrational assignments, HOMO-LUMO, MEP, NBO analysis and molecular docking study of ethyl-6-(4-chlorophenyl)-4-(4-fluorophenyl)-2-oxocyclohex-3-ene-1-carboxylate.

The optimized molecular structure, vibrational frequencies, corresponding vibrational assignments of ethyl-6-(4-chlorophenyl)-4-(4-fluoro-phenyl)-2-oxocyclohex-3-ene-1-carboxylate have been investigated experimentally and theoretically using Gaussian09 software. The title compound was optimized using the HF and DFT levels of theory. The geometrical parameters are in agreement with the XRD data. The stability of the molecule has been analyzed by NBO analysis. The HOMO and LUMO analysis is used to determine the charge transfer within the molecule. Molecular electrostatic potential was performed by the DFT method. As can be seen from the MEP map of the title compound, regions having the negative potential are over the electro negative atoms, the region having the positive potential are over the phenyl rings and the remaining species are surrounded by zero potential. First hyperpolarizability is calculated in order to find its role in non linear optics. The title compound binds at the active sites of both CypD and ß-secretase and the molecular docking results draw the conclusion that the compound might exhibit ß-secretase inhibitory activity which could be utilized for development of new anti-alzheimeric drugs with mild CypD inhibitory activity.

FT-IR, NBO, HOMO-LUMO, MEP analysis and molecular docking study of 1-[3-(4-Fluorophenyl)-5-phenyl-4,5-dihydro-1H-pyrazol-1-yl]ethanone.

The optimized molecular structure, vibrational frequencies, corresponding vibrational assignments of 1-[3-(4-fluorophenyl)-5-phenyl-4,5-dihydro-1H-pyrazol-1-yl]ethanone have been investigated experimentally and theoretically. The geometrical parameters are in agreement with XRD data. The stability of the molecule arising from hyper-conjugative interaction and charge delocalization has been analyzed using NBO analysis. The HOMO and LUMO analysis is used to determine the charge transfer within the molecule. From the MEP it is evident that the negative charge covers the carbonyl group and the positive region is over the remaining groups. The more electronegativity in the carbonyl group makes it the most reactive part in the molecule. First hyperpolarizability is calculated in order to find its role in nonlinear optics. From the molecular docking studies, it is evident that the fluorine atom attached to benzene ring and ethanone attached to the pyrazoline ring are crucial for binding and the compound might exhibit inhibitory activity against TPII and may act as anti-neoplastic agent.

Molecular structure, FT-IR, vibrational assignments, HOMO-LUMO analysis and molecular docking study of 1-[5-(4-Bromophenyl)-3-(4-fluorophenyl)-4,5-dihydro-1H-pyrazol-1-yl]ethanone.

The optimized molecular structure, vibrational frequencies, corresponding vibrational assignments of 1-[5-(4-bromophenyl)-3-(4-fluorophenyl)-4,5-dihydro-1H-pyrazol-1-yl]ethanone have been investigated experimentally and theoretically using Gaussian09 software package. The title compound was optimized using the HF/6-31G(d) (6D, 7F), B3LYP/6-31G (6D, 7F) and B3LYP/6-311++G(d,p) (5D, 7F) calculations. The B3LYP/6-311++G(d,p) (5D, 7F) results and in agreement with experimental infrared bands. The geometrical parameters are in agreement with XRD data. The stability of the molecule arising from hyper-conjugative interaction and charge delocalization has been analyzed using NBO analysis. The HOMO and LUMO analysis is used to determine the charge transfer within the molecule. Molecular electrostatic potential was also performed. From the MEP it is evident that the negative charge covers the C=O group and the positive region is over the rings. First hyperpolarizability is calculated in order to find its role in nonlinear optics. Molecular docking studies suggest that the compound might exhibit inhibitory activity against TPII and may act as anti-neoplastic agent.

Synthesis, structural and vibrational investigation on 2-phenyl-N-(pyrazin-2-yl)acetamide combining XRD diffraction, FT-IR and NMR spectroscopies with DFT calculations.

The optimized molecular structure, vibrational frequencies, corresponding vibrational assignments of 2-phenyl-N-(pyrazin-2-yl)acetamide have been investigated experimentally and theoretically using Gaussian09 software package. The title compound was optimized by using the HF/6-31G(6D,7F) and B3LYP/6-31G(6D,7F) calculations. The geometrical parameters are in agreement with the XRD data. The stability of the molecule arising from hyper-conjugative interaction and charge delocalization has been analyzed using NBO analysis. Gauge-including atomic orbital (1)H-NMR chemical shifts calculations were carried out and compared with experimental data. The HOMO and LUMO analysis is used to determine the charge transfer within the molecule. Molecular electrostatic potential was performed by the DFT method. First hyperpolarizability is calculated in order to find its role in non linear optics. From the XRD data, in the crystal, molecules are held together by strong C-H⋯O and N-H⋯O intermolecular interactions.

Crystal structure of 4-[(E)-(4-fluoro-benzyl-idene)amino]-3-methyl-1H-1,2,4-triazole-5(4H)-thione.

The title compound, C10H9FN4S, crystallizes with two mol-ecules (A and B) in the asymmetric unit. The dihedral angle between the planes of the trizole and fluoro-benzene rings is 7.3 (3)° in mol-ecule A and 41.1 (3)° in mol-ecule B. Mol-ecule A features an intra-molecular C-H⋯S hydrogen bond, which closes an S(6) ring. In the crystal, A+B dimers linked by pairs of N-H⋯S hydrogen bonds occur, generating R 2 (2)(8) loops. Weak π-π stacking contacts [centroid-centroid separation = 3.739 (6) Å] are also observed.

Crystal structure of (E)-3-(4-hy-droxy-benz-yl)-4-{[4-(methyl-sulfan-yl)benzyl-idene]amino}-1H-1,2,4-triazole-5(4H)-thione.

In the title compound, C17H16N4OS2, the triazole and methyl-thio-benzyl-idene rings are nearly coplanar, making a dihedral angle of 6.52 (12)°. An intra-molecular C-H⋯S hydrogen bond forms an S(6) ring motif. The hy-droxy-benzyl ring is almost normal to the triazole and methyl-thio-benzyl-idene rings, making dihedral angles of 78.56 (12) and 84.79 (11)°, respectively. In the crystal, mol-ecules are linked through O-H⋯N and N-H⋯O hydrogen bonds, forming layers parallel to the ac plane. The layers are linked via C-H⋯N hydrogen bonds, forming a three-dimensional structure. In addition, a short π-π inter-action is observed [inter-centroid distance = 3.764 (3) Å], involving inversion-related methyl-thio-benzyl-idene rings.

Infrared spectrum, structural and optical properties and molecular docking study of 3-(4-fluorophenyl)-5-phenyl-4,5-dihydro-1H-pyrazole-1-carbaldehyde.

The optimized molecular structure, vibrational frequencies, corresponding vibrational assignments of 3-(4-fluorophenyl)-5-phenyl-4,5-dihydro-1H-pyrazole-1-carbaldehyde have been investigated experimentally and theoretically. The title compound was optimized using at HF and DFT levels of calculations. The B3LYP/6-311++G(d,p) (5D,7F) results and in agreement with experimental infrared bands. The normal modes are assigned using potential energy distribution. The stability of the molecule arising from hyper-conjugative interaction and charge delocalization has been analyzed using natural bonding orbital analysis. The frontier molecular orbital analysis is used to determine the charge transfer within the molecule. From molecular electrostatic potential map, it is evident that the negative electrostatic potential regions are mainly localized over the carbonyl group and mono substituted phenyl ring and are possible sites for electrophilic attack and, positive regions are localized around all para substituted phenyl and pyrazole ring, indicating possible sites for nucleophilic attack. First hyperpolarizability is calculated in order to find its role in nonlinear optics. The geometrical parameters are in agreement with experimental data. From the molecular docking studies, it is evident that the fluorine atom attached to phenyl ring and the carbonyl group attached to pyrazole ring are crucial for binding and the results draw us to the conclusion that the compound might exhibit phosphodiesterase inhibitory activity.

FT-IR, molecular structure, first order hyperpolarizability, MEP, HOMO and LUMO analysis and NBO analysis of 4-[(3-acetylphenyl)amino]-2-methylidene-4-oxobutanoic acid.

4-[(3-Acetylphenyl)amino]-2-methylidene-4-oxobutanoic acid is synthesized and the structure of the compound was confirmed by IR, (1)H NMR and single crystal X-ray diffraction studies. FT-IR spectrum of 4-[(3-acetylphenyl)amino]-2-methylidene-4-oxobutanoic acid was recorded and analyzed. The crystal structure is also described. The vibrational wavenumbers were computed using HF and DFT methods are assigned with the help of potential energy distribution analysis. The NH stretching frequency is red shifted in the IR spectrum with a strong intensity from the computed frequency, which indicates the weakening of the NH bond resulting in proton transfer to the neighboring oxygen atom. The first hyperpolarizability and infrared intensities are also reported. The stability of the molecule arising from hyper-conjugative interaction and charge delocalization has been analyzed using NBO analysis. The HOMO and LUMO analysis are used to determine the charge transfer within the molecule. Molecular electrostatic potential map was performed by the DFT method. The geometrical parameters of the title compound obtained from XRD studies are in agreement with the calculated (DFT) values.

Crystal structure of 4-[(E)-(4-chloro-benzyl-idene)amino]-3-(2-methyl-benz-yl)-1H-1,2,4-triazole-5(4H)-thione.

In the title mol-ecule, C17H15ClN4S, the benzene rings form dihedral angles of 16.6 (1) and 77.2 (1)° with the triazole ring. The dihedral angle between the benzene rings is 86.6 (1)°. In the crystal, pairs of N-H⋯S hydrogen bonds form inversion dimers with graph-set notation R 2 (2)(8). Weak C-H⋯S hydrogen bonds link these dimers into layers parallel to (100). Weak intra-molecular C-H⋯S and C-H⋯N contacts are observed.

Molecular structure, FT-IR, first order hyperpolarizability, NBO analysis, HOMO and LUMO, MEP analysis of (E)-3-(4-chlorophenyl)-1-(4-fluorophenyl)prop-2-en-1-one by HF and density functional methods.

(E)-3-(4-Chlorophenyl)-1-(4-fluorophenyl)prop-2-en-1-one is synthesized by reacting 4-fluoroacetophenone and 4-chlorobenzaldehyde in ethanol in the presence of sodium hydroxide. The structure of the compound was confirmed by IR and single crystal X-ray diffraction studies. FT-IR spectrum of (E)-3-(4-chlorophenyl)-1-(4-fluorophenyl)prop-2-en-1-one was recorded and analyzed. The crystal structure is also described. The vibrational wavenumbers were calculated using HF and DFT methods and are assigned with the help of potential energy distribution method. The geometrical parameters of the title compound obtained from XRD studies are in agreement with the calculated (DFT) values. The stability of the molecule arising from hyper-conjugative interaction and charge delocalization has been analyzed using NBO analysis. The calculated first hyperpolarizability of the title compound is comparable with the reported values of similar derivatives and 63.85 times that of the standard NLO material urea. The HOMO-LUMO transition implies an electron density transfer from the chlorophenyl ring to the fluorophenyl ring. From the MEP analysis it is evident that the negative charge covers the CO group and the positive region is over the phenyl rings.

FT-IR, molecular structure, HOMO-LUMO, MEP, NBO analysis and first order hyperpolarizability of Methyl 4,4″-difluoro-5'-methoxy-1,1':3',1″-terphenyl-4'-carboxylate.

Methyl 4,4″-difluoro-5'-methoxy-1,1':3',1″-terphenyl-4'-carboxylate was prepared by the aromatization of a cyclohexenone derivative, Methyl 4,6-bis(4-fluorophenyl)-2-oxocyclohex-3-ene-1-carboxylate using iodine and methanol at reflux conditions. The structure of the compound was confirmed by IR and single crystal X-ray diffraction studies. FT-IR spectrum was recorded and analyzed. The crystal structure is also described. The vibrational wavenumbers are calculated using HF and DFT methods and are assigned with the help of potential energy distribution. The geometrical parameters of the title compound obtained from XRD studies are in agreement with the calculated (DFT) values. The stability of the molecule arising from hyper-conjugative interaction and charge delocalization has been analyzed using NBO analysis. According to the MEP analysis, negative region (red) is mainly over the carbonyl group showing large activity. The calculated hyperpolarizability of the title compound is greater than that of the standard NLO material urea and the title compound is an attractive object for future studies of nonlinear optical properties.

4-Amino-3-(4-hy-droxy-benz-yl)-1H-1,2,4-triazole-5(4H)-thione.

In the title compound, C9H10N4OS, the dihedral angle between the benzene and 1H-1,2,4-triazole-5(4H)-thione rings is 67.51 (16)°. In the crystal, mol-ecules are liked via N-H⋯O hydrogen bonds, forming chains along the c-axis direction. The chains are linked via O-H⋯S hydrogen bonds, forming corrugated layers lying parallel to the bc plane. The layers are linked via N-H⋯N and N-H⋯S hydrogen bonds, forming a three-dimensional network.