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Author: search.filters.author.Venugopala, Katharigatta Narayanaswamy

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    Synthesis and characterization of Ethyl 7-Acetyl-2-substituted 3-(substituted benzoyl)indolizine-1-carboxylates for in vitro anticancer activity
    (Chemic Publishing Company, 2016) Sandeep, C.; Padmashali, Basavaraj; Kulkarni, Rashmi S.; Venugopala, Katharigatta Narayanaswamy; Venugopala, Rashmi; Odhav, Bharti
    Efficient synthesis of a series of novel indolizines (2a-r) has been achieved by reaction between 4-acetyl-1-[2-(substituted phenyl)-2-oxoethyl]pyridin-1-ium bromide and substituted alkynes in presence of anhydrous potassium carbonate in dimethyl formamide medium. The title compounds have been characterized by spectroscopic techniques and elemental analysis. Selected compounds 2b, 2h, 2i, 2q and 2r have been screened for in vitro anticancer activity using adriamycin as positive control and it was found that compounds 2b, 2q and 2r have shown significant anticancer activity.
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    Trifluoroacetic acid: An efficient catalyst for paal-knorr pyrrole synthesis and its deprotection
    (AJC, 2013) Venugopala, Katharigatta Narayanaswamy; Prasanna, Renuka T.; Odhav, Bharti
    In the present work, we demonstrated a simple and an efficient method for the condensation of substituted aryl/heteroaryl amines with acetonylacetone in the presence of trifluoro acetic acid to afford the corresponding 2,5-dimethyl-1-substitued pyrroles using Paal-Knorr synthesis in excellent yields. Trifluoroacetic acid was used under reflux condition for the deprotection of 2,5-dimethyl-1-substitued pyrroles to their corresponding substituted aryl/heteroaryl amines in moderate yields. 2,5-Dimethyl-1-substitued pyrrole were characterized by NMR and LC-MS. The yield of the compounds was found to be excellent. - See more at: http://www.asianjournalofchemistry.co.in/user/journal/viewarticle.aspx?ArticleID=25_16_103#sthash.ZgrkcJg7.dpuf
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    Antimicrobial and antioxidant activities of substituted halogenated coumarins
    (Academic Journals, 2014-02) Kasumbwe, K.; Venugopala, Katharigatta Narayanaswamy; Mohanlall, Viresh; Odhav, Bharti
    Pathogens frequently display resistance to current drugs, which frequently lack selectivity/efficacy and have detrimental side effects. Thus, there is a constant need for novel therapeutic agents. Coumarins belong to the family of lactones, having a benzopyrone system that can be isolated from plants as well as total synthesis that can be carried out in the laboratory. To date, many chemical reactions have been established that can be used to synthesize coumarins. The synthesis of coumarins and their derivatives has attracted the attention of organic and medicinal chemists, as these are widely used as fragrances, pharmaceuticals and agrochemicals. In the present study, the antimicrobial and antioxidant activities of substituted coumarin analogue compounds have been screened. 3-(2-bromoacetyl)-2H-chromen-2-one (CMRN3) and 3-(2, 2-dibromoacetyl)-2H-chromen-2-one (CMRN6) showed bacterial growth inhibition for all the tested species except Klebsiella pneumonia and Bacillus stearothermophilus. CMRN4 and CMRN5 displayed moderate bacterial inhibition against Bacillus cereus, Micrococcus luteus, Staphylococcus aureus. CMRN3 and CMRN6 had a minimum inhibition concentration at 0.75 mg/ml against B. cereus, Bacillus coagulans, and Streptococcus faecalis. They displayed a minimum inhibitory concentration (MIC) of 1.5 mg/ml against Escherichia coli and S. aureus. (CMRN5) displayed an MIC at 0.75 mg/ml against M. luteus and 1.5 mg/ml against S. aureus. Compounds3-(2-bromoacetyl)- 6-chloro-2H-chromen-2-one (CMRN4), 3-(2-aminothiazol-4-yl)-6-bromo-2H-chromen-2-one(CMRN7), 3- acetyl-6-bromo-2H-chromen-2-one (CMRN1) exhibited potent antioxidant activity at 85, 61 and 56%, respectively, as evaluated by the DPPH free radical method.
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    Antimicrobial and antioxidant activities of substituted halogenated coumarins
    (Academic Journals, 2014-02-03) Kasumbwe, K.; Venugopala, Katharigatta Narayanaswamy; Mohanlall, Viresh; Odhav, Bharti
    Pathogens frequently display resistance to current drugs, which frequently lack selectivity/efficacy and have detrimental side effects. Thus, there is a constant need for novel therapeutic agents. Coumarins belong to the family of lactones, having a benzopyrone system that can be isolated from plants as well as total synthesis that can be carried out in the laboratory. To date, many chemical reactions have been established that can be used to synthesize coumarins. The synthesis of coumarins and their derivatives has attracted the attention of organic and medicinal chemists, as these are widely used as fragrances, pharmaceuticals and agrochemicals. In the present study, the antimicrobial and antioxidant activities of substituted coumarin analogue compounds have been screened. 3-(2-bromoacetyl)-2H-chromen-2-one (CMRN3) and 3-(2, 2-dibromoacetyl)-2H-chromen-2-one (CMRN6) showed bacterial growth inhibition for all the tested species except Klebsiella pneumonia and Bacillus stearothermophilus. CMRN4 and CMRN5 displayed moderate bacterial inhibition against Bacillus cereus, Micrococcus luteus, Staphylococcus aureus. CMRN3 and CMRN6 had a minimum inhibition concentration at 0.75 mg/ml against B. cereus, Bacillus coagulans, and Streptococcus faecalis. They displayed a minimum inhibitory concentration (MIC) of 1.5 mg/ml against Escherichia coli and S. aureus. (CMRN5) displayed an MIC at 0.75 mg/ml against M. luteus and 1.5 mg/ml against S. aureus. Compounds3-(2-bromoacetyl)-6-chloro-2H-chromen-2-one (CMRN4), 3-(2-aminothiazol-4-yl)-6-bromo-2H-chromen-2-one(CMRN7), 3-acetyl-6-bromo-2H-chromen-2-one (CMRN1) exhibited potent antioxidant activity at 85, 61 and 56%, respectively, as evaluated by the DPPH free radical method.