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Abstrack: Fluorescein derivatives have attracted a great deal of attention for ubiquitous applications on account of their unique properties. Particularly, the 2′,7′-dichlorofluorescein (DCF) is of paramount importance in biological, analytical, and industrial fields. Mainly, DCF has been employed as a reactant in reactive oxygen species (ROS) formation reactions in biological applications. It has been utilized in oxidative stress and cell spreading measurement. It has been extensively explored to analyze oxidative, respiratory burst, secretory peroxidase, and multidrug resistance-associated proteins (MRPs). It has been widely investigated for detecting/quantification of H2O2, glucose, lipid, cholesterol, other hydroperoxides, and polycationic protamine. Moreover, it has been applied to differentiate dopamine from ascorbic acid. It has also shown immense potential in biolabeling, cancer imaging, and drug delivery. Several studies demonstrated the great promise of DCF as a fluorescent probe for real-time monitoring/quantification of mercury, cadmium, zinc, arsenite, acetate, fluoride, thiocyanate, azide ions, hydrogen peroxide, ammonia, ozone, sulfur dioxide, and drug molecules. Furthermore, the use of DCF to manufacture dyesensitized solar cells and Schottky barrier devices opens up avenues for its industrial applications. Apart from presenting a comprehensive account of the immense potential of DCF in the areas mentioned above, the present review also intends to provide insight into its broader future scope for a myriad of applications to emerge.

The current studies mainly demonstrate the coumarin based azomethine-clubbed thiazoles synthesis and their in-vitro evaluation for the first time against α-glucosidase. Due to the catalytic role of α-glucosidase, it has become a precise target for the treatment of type diabetes mellitus (T2DM). The high rate of prevalence of diabetes and its associated health related problems led us to scrutinize the anti-diabetic capability of the synthesized thiazole derivatives (6a-6k). The anticipated structures of prepared compounds were confirmed through FT-IR and NMR spectroscopic methods. All the compounds showed several times potent activity than the standard drug, acarbose (IC

Dendrimers, also known as cascade molecules, arborols, cauliflower or starburst polymers. They are monodisperse, symmetrical, macromolecules with tree like 3D-architecture consists of end-groups, central core and branching units associated to periphery and possess extremely constraint size, topography and surface characteristics like density, backfolding, intrinsic viscosity, light harvesting property, photophysical properties that are fairly distinct from linear polymers. Different types of dendrimers, on the basis of their different properties and associated functional groups, has been studied yet in which one of the unique group of dendrimers is dendrtic co-polymer possess two types, first are layer block dendrimers and second are segment block dendrimers. Some new types of dendrimers like IrC3, IrCl and IrF2 have been also synthesized by divergent or convergent methods of synthesis. Dendrimers have a lot of applications in different fields like nanotechnology, medical chemistry, light harvesting materials, as sensors, antibacterial and anti-microbial activity.

A small set of four new fluorenyl chromophores (5-5a-c) was accomplished by stepwise nucleophilic substitution, Friedel-Crafts acylation, Ullman coupling, aldol condensation and cyclization reactions. The fluorene moiety was substituted at 2,7,9 and 9′ positions with diverse groups. The synthesized derivatives were characterized by FTIR, 1H-NMR and 13C-NMR spectroscopic techniques. The optical properties were evaluated by by UV-VIS absorption and Fluorescence studies. HOMO and LUMO energy levels were evaluated by electrochemical studies and were found at −5.37-5.83 eV and − 2.47-2.94 eV respectively with band gap energy values 2.88 to 2.91 eV. The band gap energy values suggested that these synthesized molecules can be manipulated in the designing of blue and green OLEDS.

The requisition of small light emitting organic molecules is on the rise in the field of organic electronics. This study is aimed at synthesis of fluorene based chromophores which possess promising optoelectronic properties. The characterization of synthesized derivatives was carried out by spectroscopy ( 1 H-NMR and 13 C-NMR) and spectrometry (EI-MS). The optical properties evaluated by using UV-Vis spectroscopy, were from 394 to 420 nm, Fluorescence ranged 48 nm-113 nm, HOMO energy levels are −6.75 eV to −7.15 eV LUMO -4.08 to −4.52eV with a band gap energy values 2.63–2.67 eV. The band gap energy values suggest that these synthesized molecules can be manipulated in the designing of blue and green OLEDS.

A series of small organic molecules were synthesized by exploiting the bay and imide positions of the perylene nucleus. The synthesized compounds 1–11 were characterized by spectroscopic and elemental analyses. These molecules show yellowish color in solution and are highly soluble in dichloromethane. Compound 7 shows a bandgap of 1.7 eV and a Stokes shift of 27. From these results, we infer that this compound can serve as structural template in the design of organic electronics. Moreover, compound 7 shows higher Td (370°C) and Tg (132°C) values, which reflect its high thermal stability.

A new series of carbazole-pyridine copolymers containing 3,3′-bicarbazolyl moiety in the main chain have been synthesized and characterized. The polymers exhibit good solubility in common organic solvents as well as good thermal stability above 300 °C and the glass transition temperature above 150 °C indicating their expediency in the device fabrication. The photophysical properties divulge emission in the blue region from 402 to 442 nm. All compounds have reversible oxidation and desirable ionization energy and electron affinity level owing to 3,3′-biscarbazole and pyridine moieties. These results signify prospective use of polymers as promising blue luminescent materials in optoelectronics applications.

The investigation has been made in the synthesis of azo hybrid rylene dyes. The hybridization of perylene bis-diimide with phenolic azo-dyes was carried out by the nucleophilic substitution (SNAr) reaction of tetrachloroperylene-3,4,9,10-bisdiimide 3 with phenolic azo-dyes 4a-g in basic medium. The hybrid dyes exhibited two absorption maxima λmax in the range 300-350, 426-438 nm in ethanol due to presence of azo linkage and highly conjugated framework of π bonds. Fluorescence spectra of these dyes in water showed sharp emission peaks with small bandwidths in the range 490-495 nm, and fluorescence quantum yield was 0.71-0.83 in comparison with standard reference fluorescein. The structures of perylene-azo dyes were elucidated by FTIR and NMR spectroscopy. Luminescence was determined by LS-100 meter which was found to be excellent in limits 0.208-0.239 cd/m(2). Cyclic voltammetric studies were made by Electrochemical Analyzer CH1830C which showed the oxidation chemical potential of these hybrid dyes.

A series of new molecular materials with varying carbazole and fluorene contents were prepared employing Suzuki coupling and their properties were compared. A variation of the core nucleus from fluorene to carbazole was a key point to study its effect on the thermal, optical and electrochemical properties. The materials were characterized by FTIR, 1H-, 13C-NMR, APCI-MS and elemental microanalyses. The synthesized materials exhibit slightly bathochromic shifted UV/Vis spectra in dilute solution and emission maxima in the blue region along with good thermal stability. The dyes with a fluorene core are electrochemically and spectrally stable with high lying HOMO levels, in contrast to the carbazole only materials, having potential as light emitting and hole transporting materials in organic light emitting diodes.

The synthesis, as well as spectroscopic and thermochemical studies of a novel class of carbazole-4-phenylpyridine co-polymers are described. The synthesis was carried out by a simple and cheaper method compared to the lengthy methods usually adopted for the preparation of carbazole–pyridine copolymers which involve costly catalysts. Thus, two series of polymers were synthesized by a modified Chichibabin reaction, i.e., by the condensation of diacetylated N-alkylcarbazoles with 3-substituted benzaldehydes in the presence of ammonium acetate in refluxing acetic acid. All the polymers were characterized by FTIR, 1H NMR, 13C NMR, UV–vis spectroscopy, fluorimetry, TGA and DSC. The weight average molecular masses (Mw) of the polymers were estimated by the laser light scattering (LLS) technique.

In the title compound, C19H14O, the dihedral angle between the two aromatic rings of the biphenyl residue is 8.0 (3)° and the dihedral angle between the two rings connected by the carbonyl C atom is 51.74 (18)°. There are no short C—H...O contacts in the crystal structure.

In the title compound, C14H12ClNO, the dihedral angle between the two aromatic rings is 11.29 (15)°. The crystal packing is stabilized by N—H...O hydrogen bonds linking the molecules into chains running along thecaxis.