Faculty Publications
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Item 2-(4-Chlorophenyl)-2-oxoethyl 4-methylbenzoate(2011) Fun, H.-K.; Loh, W.-S.; Garudachari, B.; Isloor, A.M.; Satyanarayana, M.N.In the title compound, C16H13ClO3, the dihedral angle between the benzene rings is 80.74 (8)°. In the crystal, C - H?O hydrogen bonds link the mol-ecules to form C(11) chains propagating in [010]. © Fun et al. 2011.Item 2-(4-Bromophenyl)-2-oxoethyl 4-hydroxybenzoate(2011) Fun, H.-K.; Loh, W.-S.; Garudachari, B.; Isloor, A.M.; Satyanarayana, M.N.In the title compound, C15H11BrO4, the dihedral angle between the aromatic rings is 66.77 (8)°. In the crystal, O - H?O, C - H?Br and C - H?O hydrogen bonds link the molecules, forming layers lying parallel to (101). The crystal packing is further consolidated by C - H?? inter-actions and ?-? stacking interactions [centroid-centroid distance = 3.5476 (7) Å]. © Fun et al. 2011.Item Synthesis, characterization and antimicrobial studies of some new quinoline incorporated benzimidazole derivatives(2012) Garudachari, B.; Satyanarayana, M.N.; Thippeswamy, B.; Shivakumar, C.K.; Shivananda, K.N.; Hegde, G.; Isloor, A.M.Two new series of quinoline incorporated benzimidazole derivatives (4a-i and 8a-f) were synthesized from substituted aniline and isatin through multi-step reaction. 6-substituted-4-carboxyquinolines (3a,b and 7) were synthesized by multi component one pot reactions (via Doebner reaction and Pfitzinger reaction respectively) and the targeted benzimidazole derivatives were obtained by the reaction of 6-substituted-4-carboxyquinolines (3a,b and 7) with substituted aromatic diamines in acidic media. All the newly synthesized compounds were characterized by IR, NMR mass spectral study and also by C, H, N analyses. The final compounds were screened for their in-vitro antibacterial and antifungal activity by well plate method (zone of inhibition). The results revealed that, compounds 4c, 4d, 8c and 8d showed significant antibacterial activity. The compound 8b was found to be potent antifungal agent. 4a, 8a and 8f showed moderate to good antimicrobial activity as compared to the standard drugs against all tested microbial strains. © 2012 Elsevier Masson SAS. All rights reserved.Item Design and regioselective synthesis of trifluoromethylquinolone derivatives as potent antimicrobial agents(Elsevier Masson SAS infos@masson.fr 62 rue Camille Desmoulins Issy les Moulineaux Cedex 92442, 2013) Garudachari, B.; Isloor, A.M.; Satyanarayana, M.N.; Fun, H.-K.; Pavithra, N.; Kulal, A.Three series of new trifluoromethyl substituted quinolone derivatives were synthesized (4a-f, 6a-f and 8a-f) from corresponding substituted anilines by multi-step reactions. The regioselective alkylation with different alkyl halides were carried out by approaching two different routes to get the final products in good yield. Newly synthesized compounds were characterized by spectral study and also by C, H, N analyses. Three dimensional structure of 2b and 4b were also confirmed by single crystal X-ray studies. The final compounds (4a-f, 6a-f and 8a-f) were screened for their in-vitro antibacterial and antifungal activity by well plate method (zone of inhibition). The results revealed that, compounds 4a, 6b, 6c and 8e showed significant antibacterial activity as compared to the standard drug Ciprofloxacin. The compound 8a was found to be a potent antifungal agent. © 2013 Elsevier Masson SAS. All rights reserved.Item Click chemistry approach: Regioselective one-pot synthesis of some new 8-trifluoromethylquinoline based 1,2,3-triazoles as potent antimicrobial agents(2014) Garudachari, B.; Isloor, A.M.; Satyanarayana, M.N.; Fun, H.-K.; Hegde, G.Three series of 8-trifluoromethylquinoline based 1,2,3-triazoles derivatives (5a-c, 6a-d and 7a-c) were synthesized by multi-step reactions by click chemistry approach. Synthesized compounds were characterized by spectral studies and X-ray analysis. The final compounds were screened for their in-vitro antimicrobial activity by well plate method (zone of inhibition). Compounds 5c, 6b, 8b, 11 and 12 were found to be active against tested microbial strains. The results are summarized in Tables 5 and 6. © 2014 Elsevier Ltd. All rights reserved.Item Morphology controlled n-type TiO2 and stoichiometry adjusted p-type Cu2ZnSnS4 thin films for photovoltaic applications(American Chemical Society, 2017) Varadharajaperumal, S.; Sripan, C.; Ganesan, R.; Hegde, G.; Satyanarayana, M.N.This paper presents the fabrication and characterization of stoichiometry adjusted Cu2Zn1.5Sn1.2S4.4 thin film (FTO/TiO2/CdS/CZTS/Au) photovoltaic (PV) devices. The PV devices were developed using the window layer of rutile TiO2 nanoarchitecture arrays, i.e., one-dimensional (1D) nanorods and three-dimensional (3D) combined/ hierarchical structures (nanorods with microspheres). Onedimensional (1D) nanorods and 3D combined structures of TiO2 window layers were synthesized by a hydrothermal method with different solvents without any assistance of surfactants and templates. We achieved two kinds of TiO2 nanostructures by tuning the precursor concentrations and volume by keeping a constant growth time and temperature. The detailed structural properties were studied using X-ray diffraction and high resolution transmission electron microscopy. Phase formation and chemical state of the prepared samples were examined by Raman spectroscopy and X-ray photoelectron spectroscopy. The surface morphology and luminescence studies of TiO2 nanostructures were analyzed using field emission scanning electron microscopy and cathodoluminescence techniques. The current-voltage performance of fabricated devices were measured under an AM 1.5 solar simulator. It is observed that combined structure PV device shows better efficiency (1.45%) than the nanorods alone structure (0.55%). Present work is a first attempt made to construct the inverted CZTS based solar cells. This study establishes the window layer of hierarchical TiO2 nanostructures based morphology that offers a great potential for the development of high-efficiency nonstoichiometric CZTS based solar cells. © 2017 American Chemical Society.Item Boronic Acid-Based n-Type Semiconductor for Electronic Device Application(Springer, 2022) Kagatikar, S.; Dhanya, D.; Kekuda, D.; Satyanarayana, M.N.; Kulkarni, S.D.; Karkera, C.Electron transporting, or n-type, semiconductors can serve as charge-transport materials, and are ideal for use in organic electronic devices. Boron-based small organic molecules have garnered immense research attention as the heteroatom can effectively alter the electronic structures leading to excellent photophysical and electrochemical properties. A luminescent Schiff base (E)-(4-((2-(2-hydroxybenzoyl)hydrazono)methyl)phenyl)boronic acid (SHB) was prepared by a one-pot condensation reaction between salicyloyl hydrazide and formylphenylboronic acid. The synthesized molecule was chemically characterized by infrared spectroscopy, nuclear magnetic resonance spectroscopy, and mass spectrometry. The blue-emitting boronic acid-derived molecule displayed intramolecular charge transfer, high carrier concentration, good thermal stability, a reversible reduction tendency and formation of uniform amorphous thin films. A diode was successfully fabricated via a solution processing technique with an ideality factor of 7.76. Further, AC conductivity, dielectric constant, dielectric loss, and capacitance values in a frequency range of 10–1000 Hz were extracted from dielectric studies. The dielectric constant of SHB was found to be 9.71 with an AC conductivity of 6.34 × 10−9 Ω−1 cm−1 at 1000 Hz. Graphical Abstract: [Figure not available: see fulltext.] © 2022, The Author(s).Item Pyrene-based chalcones as functional materials for organic electronics application(Elsevier Ltd, 2023) Kagatikar, S.; Dhanya, D.; Kekuda, D.; Satyanarayana, M.N.; Kulkarni, S.D.; Sudhakar, Y.N.; Vatti, A.K.; Sadhanala, A.Though new generation organic electronic devices have evolved from mere scientific perceptions to real-life marketed applications, considerably less research attention has been focused on n-type or electron transporting small molecule semiconductors. The present study is focused on the exploration of structural, thermal, electrochemical, electrical, and optical properties of two pyrene-based chalcones: PC1 and PC2, synthesized through Claisen Schmidt condensation reaction. The chalcones displayed good thermal stability and wide bandgap n-type semiconducting behaviour with high charge carrier concentration and dielectric constant. The experimental evidences including fluorescence measurements, nanoaggregate size, and morphology analysis, supported by DFT calculations and molecular dynamic simulations advocated the intramolecular charge transfer and aggregation-induced enhanced emission features of the molecules. Successful fabrication of a diode in combination with the current-voltage characteristics established the candidature of PC1 and PC2 for electro-optical devices. The dielectric studies were performed to measure dielectric constant and AC conductivity at different frequency ranges. The cyclic voltammetry and AC impedance response of PC2 differed from PC1 due to the inclusion of a fluorine atom in the molecular scaffold. Further, the functional implication of PC2 as an electrode material was explored by constructing a supercapacitor, which offered a specific capacitance of 220 Fg-1 at a scan rate of 10 mV s−1. Moreover, these chalcone-based organic semiconductors displayed high thermal and charge carrier concentration as well as compatibility with other layers in an OLED device. Hence PC1/PC2 can be further investigated as dopants along with other emissive layers as host materials in OLEDs. © 2022 Elsevier B.V.