Fluorescent Styryl Dyes from 4-Chloro-2-(Diphenylamino)-1, 3-Thiazole-5-Carbaldehyde-Synthesis, Optical Properties and TDDFT Computations.

4-Chloro-2-(diphenylamino)-1,3-thiazole-5-carbaldehyde was reacted with an active methylene compounds, cyanomethyl benzimidazole, cyanomethyl benzothiazole, barbituric acid and Meldrum's acid under Knoevenagel conditions to give novel push-pull styryl chromophores 8a-8d. The synthesized styryl chromophores were characterized by FT-IR, Mass and (1)H NMR spectral analysis. The photophysical characteristics of these styryl chromophores were evaluated.

Synthesis of novel carbazole fused coumarin derivatives and DFT approach to study their photophysical properties.

Novel coumarin derivatives have been synthesized by the classical Knoevenagel condensation of 4-hydroxy-9-methyl-9H-carbazole-3-carbaldehyde with active methylene compounds and characterized. Effect of solvent polarity on the photophysical properties, absorption and emission has been studied. The photophysical properties of the synthesized coumarins have been compared with some of the established analogous coumarin derivatives.

Synthesis of novel carbazole based styryl: rational approach for photophysical properties and TD-DFT.

The synthesis and solvatochromic behavior of four novel carbazole based fluorescent styryl dyes were explained. In chlorinated solvents such as DCM and chloroform, these dyes show bathochromic shift in their absorption as well as emission. The styryl dyes 6b and 6c show solid state yellow fluorescence.

Fluorescent styryl dyes based on novel 4-methoxy-9-methyi-9H-carbazole-3-carbaldehyde--synthesis, photophysical properties and DFT computations.

Novel carbazole based styryl derivatives (6a-6c) having styryl group at third position and a methoxy substitution were synthesized by condensing 4-methoxy-9-methyl-9H-carbazole-3-carbaldehyde 3 and different active methylene derivatives (5a-5c). Evaluated photophysical properties of these synthesized novel chromophores, studied the effect of solvent polarity on absorption, emission and quantum yield of these styryl derivatives. DFT and TD-DFT computations are carried out to study structural, molecular, electronic and photophysical parameters of dyes.

TDDFT investigation of the electronic structures and photophysical properties of fluorescent extended styryl push-pull chromophores containing carbazole unit.

Push-pull chromophores attached to carbazole based π-conjugating spacers bearing N-alkylamino donors, cyanovinyl and carbethoxy acceptors have been studied by the means of UV-Visible measurements. The intramolecular charge transfer (ICT) of these π-conjugated systems has also been tested by investigating the ability of the solute molecules to undergo shifts in their fluorescence emission maxima with increasing solvent polarity. Density Functional Theory [B3LYP/6-31G(d)] and Time Dependent Density Functional Theory [TD-B3LYP/6-31G(d)] computations have been used to have more understanding of the structural, molecular, electronic and photophysical parameters of push-pull dyes.

Synthesis of new ESIPT-fluorescein: photophysics of pH sensitivity and fluorescence.

ESIPT-inspired benzimidazolyl substituted fluorescein dyes were synthesized. PH-sensitivity was determined by the photophysical property measured at a physiological possible pH range. Fluorescence quantum efficiency values were calculated independently at two different emissions.

Synthesis, Characterization, Thermal Properties, and Antimicrobial Activities of 5-(Diethylamino)-2-(5-nitro-1H-benzimidazol-2-yl)phenol and Its Transition Metal Complexes.

Synthesis and antimicrobial activities of new metal [Co(II), Cu(II), Ni(II), and Fe(II)] complexes from 5-(diethylamino)-2-(5-nitro-1H-benzimidazol-2-yl)phenol are described. The newly synthesized ligands were characterized by IR, (1)H NMR, and LC-MS analysis, and metal-ligand complex formations were confirmed by using atomic absorption spectroscopy and elemental analysis. All complexes show significant in vitro antibacterial activities against E.