Publications by authors named "Resmi Raghunandan"

In recent years, the synthesis of metal-organic framework (MOF)─nanocomposites has received wide attention from the scientific fraternity due to the presence of a tunable hierarchical architecture and invasive versatility in applications. The present work focuses on the solvothermal synthesis of a novel hybrid MOF-nanocomposite through the impregnation of Mn-doped ZnO nanoparticles onto the matrix of a pioneer metal-organic framework that is composed of zinc metal connected with terephthalic acid linkers (MOF-5). The hierarchical arrangements of the prepared material were further assessed by Fourier-transform infrared spectroscopy (FTIR), powder X-ray diffraction (PXRD), high-resolution transmission electron microscopy (HR-TEM), UV-visible, photoluminescence (PL), and dynamic light scattering (DLS) measurements.

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Recently, the synthesis, characterization, and structural evaluation of metal-organic framework (MOF) nanocomposites gain more attention due to the versatility in their applications. In the present work, the fluorescent active ZnO@MOF-5 composite was synthesized by encapsulating ZnO nanoparticles into the zinc terephthalate metal-organic framework (MOF-5). ZnO nanoparticles were prepared by a green method using the leaf extract of .

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Sterically hindered naphthalene-substituted biphenyls and terphenyls were synthesized in good yields, by Michael addition of a conjugate base of core-substituted phenylacetones to substituted 2-oxo-2H-pyran-3-carbonitriles at room temperature under alkaline conditions. These diversely functionalized benzenes (1,2-teraryls or 1,3-teraryls), bearing naphthyl and substituted aryl rings, show the phenomenon of atropisomerism, with one or two stereogenic biaryl axes. The resolution of the respective four atropisomers of the naphthalene-substituted biphenyls and terphenyls bearing 1,2-type or 1,3-type chiral biaryl axes was achieved by HPLC on a chiral phase.

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A novel series of thermally stable blue light emitting quateraryls with a piperidine donor and a nitrile acceptor was prepared from a ketene- S, S-acetal under mild conditions without using an organometal catalyst. The performance of a blue quateraryl 6e was investigated by fabricating a multilayer OLED with a configuration of ITO/PEDOT:PSS (40 nm)/quateraryl (60 nm)/BCP (6 nm)/Alq(3) (20 nm)/LiF (0.5 nm)/Al (200 nm), which exhibited blue emission with a low turn on voltage of 4 V at a brightness of 0.

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7-Methoxy-3-phenyl-4-phenylvinyl benzopyran-2-ones and the corresponding 2,2-dimethyl-benzopyrans, substituted with different alkylamino residues were synthesized. Except compound 13e, all compounds showed high level of estrogen agonistic activity (>81 %) whereas, compounds 13 b-e and 15a showed significant estrogen antagonistic activity (>20 %). X-Ray analysis of a 7-methoxy-3-phenyl-4-phenylvinyl benzopyran-2-one derivative 13d showed its structural resemblance to endogenous estrogen, 17beta-estradiol.

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Substituted amidoalkyl derivatives of 2,3-diarylacrylophenones carrying the amide chain on the 3-aryl residue have been prepared by reacting corresponding phenolic 2,3-diarylacrylophenones with haloalkyl carboxylic acid esters, their hydrolysis and subsequent treatment with different alkyl amines. Compounds thus prepared were evaluated for their relative binding affinity (RBA) towards estrogen receptors (ER), estrogen agonistic and antagonistic activities. Out of eleven amide derivatives thus prepared, compounds 7, 13, 15-19, 23, 24 showed significant estrogen antagonistic activity.

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A general, two-step, highly efficient synthesis of 1,2-diaryl-, 1,2,3-triaryl-, and 1,2,3,4-tetraarylbenzenes from simple stitching of alpha-oxo-ketene-S,S-acetals and active methylene compounds via a lactone intermediate is described. This procedure offers easy access to highly functionalized arylated benzenes that contain sterically demanding groups in good to excellent yields. The novelty of the procedure lies in the construction of aromatic compounds with the desired conformational flexibility along the molecular axis in a transition-metal-free environment through easily accessible precursors.

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Generation of phosphocholine by choline kinase is important for phosphatidylcholine biosynthesis via Kennedy pathway and phosphatidylcholine biosynthesis is essential for intraerythrocytic growth of malaria parasite. A putative gene (Gene ID PF14_0020) in chromosome 14, having highest sequence homology with choline kinase, has been identified by BLAST searches from P. falciparum genome sequence database.

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[reaction: see text] An expeditious synthesis of unsymmetrical biaryls functionalized with electron-withdrawing or -donating substituents is described and illustrated by carbanion-induced ring transformation of 2H-pyran-2-one using acetyltrimethylsilane (ATMS) as a novel reagent in good yield. The novelty of the reaction lies in the creation of an aromatic ring from 2H-pyran-2-ones via two-carbon insertion from ATMS used as a source of carbanion.

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