Spectroscopic investigations, concentration dependent SERS, and molecular docking studies of a hydroxybenzylidene derivative.

Spectroscopic analysis, density functional theory (DFT) studies and surface enhanced Raman scattering (SERS) of (E)-N'-(5-chloro-2-hydroxybenzylidene)-4-trifluoromethyl) benzohydrazide (CHTB) have been studied on different silver colloids in order to know the particular chemical species responsible for the spectra. Very significant shifts are observed for Raman and SERS wavenumbers. Observed changes in the υ-ring modes may be due to surface interaction of the π-electrons and the presence of this suggested that RingII is more tilted in both cases than RingI and the molecule assumes a tilted orientation for the concentration 10-3 M. Orientation changes are seen in concentration dependent SERS spectra. The molecular electrostatic potential has also been constructed to determine the electron rich and poor site of CHTB. The molecular docking studies indicate that the binding affinity and hydrogen bond interactions with the receptors may be supporting evidence for further studies in designing other pharmaceutical applications of CHTB.Communicated by Ramaswamy H. Sarma.

Conformational analysis and quantum descriptors of two new imidazole derivatives by experimental, DFT, AIM, molecular docking studies and adsorption activity on graphene.

1-[2-(2-hydroxy-3-methoxy-5-(4-methoxyphenylazo)benzaldeneamino)ethyl]-3-methyl-3H-imidazole (HMY) and 1-[2-(2-hydroxy-3-methoxy-5-(4-methylphenylazo)benzaldene amino)ethyl]-3-methyl-3H-imidazole (HMM) were synthesized and characterized using spectral analysis. Conformational analysis has been achieved using potential energy scan for different rotable bonds for obtaining the lowest energy conformer. Conformer with minimum energy is obtained along the dihedral angle N30-C31-C34-N37. QTAIM analysis gives nature and strength of hydrogen bonding interactions. UV-Vis, electrostatic potential and chemical descriptors are analyzed. Interaction of HMY and HMM with graphene is analyzed in terms of SERS activity. Chemical reactivity descriptors were investigated for graphene-drug systems. NLO activity of parent drugs and its graphene complexes show good activity. The wavenumber downshift of different modes is noted. Title molecules exhibit inhibitory activity against cytochrome C peroxidase. Interactions with graphene sheets are theoretically predicted for the title compounds.

Spectral characterization, thermochemical studies, periodic SAPT calculations and detailed quantum mechanical profiling various physico-chemical properties of 3,4-dichlorodiuron.

A set of experimental and computational techniques have been applied for the understanding of fundamental spectroscopic and reactive properties of 3-(3,4-dichlorophenyl)-1,1-dimethylurea (diuron) compound. Experimental techniques employed in this study encompassed spectroscopic characterization via IR and Raman approaches, while optical properties were studied by measurements of UV/Vis spectra. The thermogravimetric analysis was also studied in order to analyze the stability of diuron. Aside from the determination of reactive properties, DFT calculations on isolated molecules were also used to thoroughly visualize and analyze spectroscopic properties such as IR and UV/Vis. MD simulations were used in order to understand interactions with water, while periodic DFT calculations were used in order to analyze band structure and density of states of the diuron crystal structure. Since the crystal structure of diuron is known, it was used in order to extract the relevant molecular pairs and investigate interactions between them by DFT and symmetry adapted perturbation theory approaches (SAPT).

Detailed quantum mechanical, molecular docking, QSAR prediction, photovoltaic light harvesting efficiency analysis of benzil and its halogenated analogues.

The structural, spectroscopic various physico-chemical and biological characteristics of the organic molecule benzil (BZL) and derivatives, 1,2-bis(4-methylphneyl)-1,2-ethanedione (DMB), 4,4'-difluorobenzil (DFB), 4,4'-dichlorobenzil (DCB) and 4,4'-dibromobenzil (DBB) have been studied by various computational methods. The experimental and scaled simulated Raman and IR spectra were compared and found close agreement. Assignments of important peaks are also presented. Detailed information pertaining to the local and global reactivity and other properties like electrophilic and nucleophilic characteristics were analysed. The hyperactive pressure was measured in terms of polarizability and corresponding biological properties were validated to identity reactive sites. Prediction of Activity Spectral Studies (PASS) predicts the biological activity of the compounds and it is found that the candidate molecules can be used as feruloyl esterase inhibitor, bisphosphoglycerate phosphatase inhibitor and Prolylaminopeptidase inhibitor. The crystals structures of those receptors are taken from the protein data bank and docking studies indicates stable complex with the receptors and candidate molecules. Light harvesting efficiency, followed by photovoltaic modelling shows that DMB is the best compound to be used in the DSSC to get the best output.

Conformational profile, vibrational assignments, NLO properties and molecular docking of biologically active herbicide1,1-dimethyl-3-phenylurea.

1,1-Dimethyl-3-phenylurea (known as fenuron) which is a phenyl urea-based widely used herbicide exhibits interesting structural and conformational properties and a notable biological activity. A detailed analysis on the vibrational, molecular and electronic characteristics of fenuron has been carried out. Potential energy scans (PESs) performed at the B3LYP/6-311++G(d,p) level of theory predicted two possible minima corresponding to the optimized anti and synforms resulting from the internal rotation about the N-C bond. The presence of an auxochrome together with the interaction with DMSO solvent exhibited a blue shift corresponding to the C=O orbitals. Delocalization of HOMO and LUMO orbital facilitated the charge transfer effect in the molecule. The calculated HOMO-LUMO energies, chemical potential, energy gap and global hardness suggested a low softness value for the compound while its biological activity was described by the value of electrophilicity. Chlorine substitution in the phenyl ring influenced the orbital delocalization for ortho and para substitutions but that of meta remained unaffected. NLO properties were noticed to increase due to chlorine substitution in the parent molecule. The docking results suggested that the compound exhibits an inhibitory activity against mitochondrial ubiquinol-cytochrome-c reductase and can be developed as a potential anticancer agent.