Studies on interaction between an imidazole derivative and bovine serum by spectral methods.

The interaction between a trifluoromethyl substituted imidazole derivative 2-(4-(trifluoromethyl)phenyl)-1-phenyl-1H-imidazo[4,5-f] [1,10] phenanthroline (tfmppip) and bovine serum albumin (BSA) was investigated by solution spectral studies. The observed experimental result shows that the imidazole derivative has strong ability to quench the fluorescence of BSA by forming complex which is stabilized by electrostatic interactions. The effective quenching constants (k(sv)) were 2.

Characterization, photophysical and DFT calculation study on 2-(2,4-difluorophenyl)-1-(4-methoxyphenyl)-1H-imidazo[4,5-f][1,10]phenanthroline ligand.

The synthesized imidazole derivative 2-(2,4-difluorophenyl)-1-(4-methoxyphenyl)-1H-imidazo[4,5-f][1,10] phenanthroline (dfpmpip) has been characterized using IR, mass, (1)H, (13)C NMR and elemental analysis. The photophysical properties of dfpmpip have been studied using UV-visible and fluorescence spectroscopy in different solvents. The solvent effect on the absorption and fluorescence bands has been analyzed by a multi-component linear regression.

Photophysical and computational studies of novel heterocyclic imidazole derivatives containing trifluoromethyl group substituent.

Phenanthrimidazole ligands with potential electron withdrawing trifluoromethyl substituent have been synthesized and characterized using IR, mass and NMR spectral studies. The effect of solvent on their absorption and emission have been analysed in detail by Kamlet-Taft Catalan approach. The introduction of trifluoromethyl substituent results in a significant blue shift in emission when compared to its parent compound.

Photophysical studies of fused phenanthrimidazole derivatives as versatile π-conjugated systems for potential NLO applications.

Two new heterocyclic imidazole derivatives consists of π-conjugated system attached to a phenanthrimidazole moiety have been synthesized in moderate yield by the condensation of 1,10-phenanthroline-5,6-dione with substituted aromatic aldehydes and 4-methoxyaniline in the presence of ammonium acetate in ethanol medium. The photophysical properties of these imidazole derivatives were studied in several solvents. These derivatives were evaluated concerning their solvatochromic properties and molecular optical nonlinearities.

New iridium complexes with cyclometalated 2-arylimidazole ligands as highly efficient saturated green emitters.

Phosphorescence studies of a series of heteroleptic cyclometalated iridium(III) complexes have been carried out. From the photoluminescent properties, it was found that these complexes possess dominantly (3)MLCT and (3)π-π* excited states. The solvent shifts are interpreted in terms of Reichardt-Dimroth solvent E(T) parameters and Marcus theory.

Fluorescence spectral studies of some imidazole derivatives.

The photophysical properties of imidazole derivatives namely 2-(2,4-difluorophenyl)-4,5-dimethyl-1-p-tolyl-1H-imidazole and N,N-dimethyl-4-(4,5-dimethyl-2-phenyl-1H-imidazol-1-yl)benzenamine, synthesized from an unusual four components assembling, were studied in several solvents. Polarization also plays major role in the increase of excited-state dipole moment (μ(e)). From the spectral results, it was found that there is equilibrium between neutral species and monocationic (MC) species in polar aprotic and polar protic solvents.

Synthesis, spectral studies and solvatochromic analysis of novel imidazole derivatives.

Bioactive imidazole derivatives were synthesized and characterized by spectral techniques. The photophysical properties of imidazole derivatives were studied in several solvents. The observed spectral shift is attributed to a loss of planarity in the excited state provided by the non-co-planarity of the aryl rings attached to C(2) and N(1) atoms of the imidazole ring.

Light-emitting materials from cyclometalated heteroleptic iridium(III) complexes--A physicochemical study.

Phosphorescent studies of 2-arylimidazole heteroleptic cyclometalated iridium(III) complexes with picolinic acid as the ancillary ligand were made. The observed experimental data reveal that these complexes possess dominantly (3)MLCT and (3)π-π* excited states and the solvent shift of these complexes is interpreted by Reichardt-Dimroth and Marcus solvent functions. The results are consistent with prior assignments on the absorption band to a metal-to-ligand charge transfer excited state associated with chelating ligand.

Optical properties of organic nonlinear optical crystal--a combined experimental and theoretical study.

The optical properties of the synthesized imidazole derivative, 1-(4-methoxyphenyl)-4,5-diphenyl-2-styryl-1H-imidazole, has been studied both experimentally and theoretically. Fluorescence enhancement have been found in the presence of transition metal ions and this may result from the suppression of radiationless transitions from the n-π* state in the chemosensors. Quantum chemical calculations of heat of formation, optimized geometry, NLO, HOMO-LUMO, MEP and NBO analysis of 1-(4-methoxyphenyl)-4,5-diphenyl-2-styryl-1H-imidazole (mpdsi) have been carried out by using density functional theory (DFT/B3LYP) method with 6-31G(d,p) as basis set.

Physicochemical and solvatochromic analysis of an imidazole derivative as NLO material.

Bioactive imidazole derivative, 2-(2,4-difluorophenyl)-1-phenyl-1H-imidazo[4,5-f][1,10]phenanthroline, has been synthesized and characterized by IR, UV-vis, NMR and elemental (CHN) analysis. The electric dipole moment (μ) and the hyperpolarizability (β) have been studied both experimentally and theoretically, which reveals that the synthesized imidazole derivative possesses non-linear optical (NLO) behavior. This chromophore possess more appropriate ratio of off-diagonal versus diagonal β tensorial component (r=β(xyy)/β(xxx)=-0.

Luminescent study on the binding interaction of bioactive imidazole with bovine serum albumin-A static quenching mechanism.

Novel bioactive imidazole derivatives were synthesized and characterized by NMR spectra, mass and CHN analysis. The interaction between the imidazole derivative and bovine serum albumin (BSA) was investigated by fluorescence and UV-vis absorption spectroscopy. The fluorescence quenching of BSA by the imidazole derivatives may be due to the formation of imidazole-BSA complex.

Binding interaction of bioactive imidazole with bovine serum albumin--a mechanistic investigation.

A novel Y-shaped imidazole derivative 4-((E)-2-(4,5-diphenyl-1-p-tolyl-1H-imidazol-2-yl)vinyl)phenol has been synthesized and characterised by IR, UV-vis, mass and NMR spectral techniques. The mutual interaction of this imidazole derivative (DPTIV) with bovine serum albumin (BSA) was investigated using photoluminescent studies. The fluorescence quenching mechanism of BSA by DPTIV was analyzed and the binding constant has been calculated.

Synthesis, crystal structure, Kamlet-Taft and Catalan solvatochromic analysis of novel imidazole derivatives.

Novel imidazole derivatives were synthesized and its crystal structure has been studied by single crystal XRD analysis. The photophysical properties of these imidazole derivatives were studied in several solvents, which include a wide range of apolar, polar and protic media. The observed lower fluorescence quantum yield may be due to an increase in the non-radiative deactivation rate constant.

A physiochemical study of azo dyes: DFT based ESIPT process.

Azo linked dye derivatives were synthesized and characterized by NMR, mass and elemental analysis. An excited state intramolecular proton transfer (ESIPT) in hydroxy Schiff base has been analyzed, and found that two distinct ground state isomers of I and II are responsible for the observed dual emission. DFT calculation on energy, dipole moment, charge distribution of the rotamers in the ground and excited states support the ESIPT process.

Photophysical properties of novel picrate derivatives--solvent effect.

H and (13)C NMR spectra were recorded for some novel picrate derivatives derived from 3,3-dimethyl-2,6-diarylpiperidin-4-ones and 3-benzyl-2,6-diarylpiperidin-4-one. The photophysical properties of the picrate derivatives were studied in several solvents, which include a wide range of apolar, polar and protic media. The observed lower fluorescence quantum yield may be due to an increase in the non-radiative deactivation rate constant.

Solvatochromic studies of fluorescent azo dyes: Kamlet-Taft (π*, α and β) and Catalan (S(pp), S(A) and S(B)) solvent scales approach.

A new metal ion-responsive azo-based fluorescent probes have been synthesized and characterized by NMR spectral techniques. Steady-state fluorometric study has been used to analyze the spectroscopic and photophysical characteristics of dye derivatives in various solvents. The fluorescence properties of these dyes are strongly solvent dependent, the wavelength of maximum fluorescence emission shifts to the red.

Solvatochromic analysis of some N-nitroso oxime derivatives--Taft and Catalan approach.

Some novel N-nitroso oxime derivatives were synthesized and characterized by (1)H, (13)C, (1)H-(1)H and (1)H-(13)C COSY NMR spectra. The spectra of all these N-nitroso oximes reveal the presence of two isomers labelled as E (-NOH group is anti to N-N=O moiety) and Z (-NOH group is syn to N-N=O moiety) in solution and the coupling constants ruled out the possibility of normal chair conformation. From the theoretical studies and coupling constant values it was found that both E (major) and Z (minor) isomers of N-nitroso oximes exist as an equilibrium mixture of CA and boat conformation (B(1)) and this was also supported by DFT calculation.

Spectrofluorometric studies on the binding interaction of bioactive imidazole with bovine serum albumin: a DFT based ESIPT process.

Bioactive imidazole derivatives were synthesized and characterized by NMR spectra, mass and CHN analysis. An excited state intramolecular proton transfer (ESIPT) process in hydroxy imidazole has been studied using emission spectroscopy. In hydrocarbon solvent, the tautomer emission predominates over the normal emission and in alcoholic solvent like ethanol; a dramatic enhancement of normal emission is observed which was due to increased solvation.

Mechanistic investigation on binding interaction of bioactive imidazole with protein bovine serum albumin--a biophysical study.

The interaction between bioactive imidazole derivative (PPP) and bovine serum albumin (BSA) was investigated using fluorescence and UV-vis spectral studies. The experimental results showed that the fluorescence quenching of BSA by imidazole derivative was the result of the formation of BSA-PPP complex and the effective quenching constants (K(SV)) were 2.66×10(4), 2.

Physicochemical studies of green phosphorescent light-emitting materials from cyclometalated heteroleptic iridium(III) complexes.

A series of novel imidazole ligands were synthesized and characterized. Phosphorescence studies of series of heteroleptic cyclometalated iridium(III) complexes reveal that these complexes possess dominantly (3)MLCT and (3)π-π* excited states and the solvent shifts of these complexes are interpreted by Richardt-Dimroth and Marcus solvent functions. The results consistent with prior assignments on the absorption band to a metal-to-ligand charge transfer excited state associated with chelating ligand.

An intramolecular charge transfer fluorescent probe: synthesis, structure and selective fluorescent sensing of Cu+2.

A series of substituted imidazoles have been synthesized in very good yield under solvent free condition by grinding 1,2-diketone, aromatic aldehyde and ammonium acetate in the presence of molecular iodine as the catalyst. The short reaction time, good yield and easy workup make this protocol practically and economically attractive and characterized by NMR spectra, X-ray, mass and CHN analysis. An excited state intramolecular proton transfer (ESIPT) process in hydroxy imidazoles (dpip and dptip) have been studied using emission spectroscopy and it was detected that the two distinct ground state rotamers are responsible for the normal and the tautomer emissions.

Displacement reaction using ibuprofen in a mixture of bioactive imidazole derivative and bovine serum albumin--a fluorescence quenching study.

The mutual interaction of imidazole derivative (PIPP) with bovine serum albumin (BSA) was investigated using photoluminescent studies. The fluorescence quenching mechanism of BSA by PIPP was analyzed and the binding constant was calculated. The binding distance between PIPP and BSA was obtained based on the theory of Forester's non-radiation energy transfer.

Physicochemical studies of molecular hyperpolarizability of imidazole derivatives.

A series of substituted imidazoles have been synthesized in very good yield under solvent free condition by grinding 1,2-diketone, arylaldehyde, arylamine and ammonium acetate in the presence of molecular iodine as the catalyst. The short reaction time, good yield and easy workup make this protocol practically and economically attractive and the imidazoles are characterized by NMR spectra, X-ray, mass and CHN analysis. The push-pull character of series of imidazoles have been analyzed by the quotient of the occupations of the bonding (π) and anti-bonding (π*) orbitals of the central linking -N=C-C=C- unit.

A physiochemical study of excited state intramolecular proton transfer process-Luminescent chemosensor by spectroscopic investigation supported by ab initio calculations.

A group of novel Schiff base derivatives were synthesized and characterized by NMR spectra, X-ray, mass and CHN analysis. An excited state intramolecular proton transfer (ESIPT) process in hydroxy Schiff base (SB4) has been studied using emission spectroscopy and it was detected that the two distinct ground state isomers of I and II are responsible for the emission. The comparison of the emission wavelength in hydrocarbon solvent strongly supports that trans enol form predominates over the cis enol form for Schiff base (SB4).