Publications by authors named "Mannathusamy Gopalakrishnan"

Unlabelled: Aims and Scope: The 2-hydroxy-1,4-naphthoquinone (lawsone) and 2,5-dihydroxy-1, 4-naphthoquninone (5-hydroxylawsone) are synthesized by one step process. The process involves an inexpensive catalyst urea hydrogen peroxide and a base (t-BuOK) in alcohol for the transformation of 1-naphthol or 2,5-dihydroxynaphthalene to lawsone or its derivatives in the presences of oxygen. The process is further directed to produce lawsone or its derivatives, with no extraneous heating to make it energetically efficient.

View Article and Find Full Text PDF

A novel sustained release delivery system of ciprofloxacin was developed. The system consists of a viscosity enhancer plus a penetration enhancer to overcome penetration barriers and loss due to wash-out and thus achieve the desired ciprofloxacin ocular absorption. A macromolecule of piperazine core 1,3,5-triazine dendrimer with eight molecules of ciprofloxacin drug as a surface moiety has been synthesized in five steps.

View Article and Find Full Text PDF

A new series of novel heterocyclic compounds containing both tetrazoles and piperidine nuclei together, namely, 1-(1-aryl-1H-tetrazol-5-yl)-2-(piperidin-1-yl)ethanone (22-28), were synthesized by the treatment of the respective 2-chloro-1-(1-aryl-1H-tetrazol-5-yl)ethanone (15-21) with piperidine in acetonitrile for 6 h. A series of novel tetrazole substituted piperidine derivatives were synthesized and evaluated for their antimicrobial activity using serial dilution method. The structures of the synthesized compounds were characterized by IR, (1)H NMR, (13)C NMR, mass spectral data, and elemental analysis.

View Article and Find Full Text PDF

In the title compound, C26H22ClFO2, the cyclo-propane ring is disordered over two orientations, with site-occupancy factors of 0.64 (2) and 0.36 (2).

View Article and Find Full Text PDF

Chemoprevention by medicinal plants has evolved as a practical strategy to control the incidence of cancer. Azadirachta indica (neem) containing various bioactive components is a promising candidate for chemoprevention. The present study was undertaken to evaluate the chemopreventive efficacy of the bioactive subfractions ethyl acetate chloroform insoluble fraction (ECIF) and the methanol ethyl acetate insoluble fraction (MEIF) following activity-guided fractionation of neem leaf extract.

View Article and Find Full Text PDF

Novel 1,1'-(5,5'-(1,4-phenylene)bis(3-aryl-1H-pyrazole-5,1-(4H,5H)-diyl))diethanones 7-12 were tested for their antimicrobial activity by disc diffusion and twofold serial dilution method against the tested bacterial and fungal strains. Compounds 7 against Micrococcus luteus, 8 against β-Heamolytic streptococcus, M. luteus, Klebsiella pneumonia, Microsporum gypseum, 9 against Staphylococcus aureus, Shigella flexneri, Vibreo cholerae, Pseudomonas aeruginosa, Aspergillus flavus, Mucor indicus, 10 against Salmonella typhii, S.

View Article and Find Full Text PDF