NMKRV College for Women

Bangalore, India

NMKRV College for Women

Bangalore, India
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Vanitha G.K.,Maharanis Science College for Women | Ramaiah M.,NMKRV College for Women | Vaidya V.P.,Kuvempu University
Journal of Chemical and Pharmaceutical Research | Year: 2013

Ethyl 3-aminonaphtho [2, 1-b] furan-2-carboxylate 1, which was obtained by Thorpe-Zeigler cyclization reaction between 2-hydroxy-1-naphthonitrile and ethylchloroacetate in presence of weak base-on treatment with formamide produced 3, 4-dihydro-4-oxo-naphtho[2, 1-b] furo[3, 2-d] pyrimidine 2. The oxopyrimidine2 was converted into 4-chloronaphtho[2, 1-b] furo[3, 2-d] pyrimidine 3 by refluxing it with phosphorous oxychloride. Various 3-amino-5-aryl-1, 3, 4-thiadiazoles 4a-f were synthesized by reaction between appropriately substituted aromatic acids with thiosemicarbazide. The thiazoles4a-f on treatment with 4-chloronaphtho[2, 1-b] furo[3, 2-d] pyrimidine 3 using triethylamine as a catalyst in DMF, resulted in the formation of desired products. 4-substituted-naphtho[2, 1-b] furo[3, 2-d] pyrimidine-2-amino-5-aryl-1, 3, 4-thiadiazoles. 5a-f. The newly synthesized compounds have been characterized by analytical and spectra studies. Evaluation of the synthesized compounds for antibacterial activity against Staphylococcus aureus, Bacillus subtillis, Bacillus polymixa, Vibrio cholera and Salmonella typhi using Gentamycin as a standard by agar diffusion method, indicated that some of the compounds possessed moderate antibacterial activity.


Veena K.,Maharanis Science College for Women | Ramaiah M.,NMKRV College for Women | Shashikaladevi K.,Maharanis Science College for Women | Avinash T.S.,University of Mysore | Vaidya V.P.,Kuvempu University
Journal of Chemical and Pharmaceutical Research | Year: 2011

2-Hydroxy-1-naphthaldehyde served as a good starting material for the synthesis of the azines, which was prepared from 2-naphthol by Reimer-Tiemann reaction. The hydroxy aldehyde on treatment with phenacyl bromide, under basic condition, underwent both condensation and cyclization and furnished 2-benzoylnathpho[2,1-b]furan 1, Nitration of ketone 1, under mild reaction condition, yielded 2-(3′,5′-dinitrobenzoyl)-3-nitronaphtho[2,1-b]furan 2, as evidenced by its mass spectrum. The reaction of the compound 2, with hydrazine hydrate, resulted in the formation of corresponding hydrazone 3. Various azines 4a-g were obtained when the hydrazine 3 was treated with, appropriate aldehydes by using different reaction condition in absence and in presence of hydrochloric acid as a catalyst. All the newly synthesized compounds have been characterized by analytical and spectral studies and were screened for antibacterial activity against Bacillus subtilus and Alcaligenes fecalies and antifungal activity against Aspergillus nidulans, Aspergillus parasiticus and Aspergillus terius.


Veena K.,Maharanis Science College for Women | Shashikaladevi K.,Maharanis Science College for Women | Shanmukha I.,Scs College Pharmacy | Ramaiah V.,NMKRV College for Women | Vaidya V.P.,Kuvempu University
Pharmacologyonline | Year: 2011

The present study was undertaken to evaluate antioxidant activity of the synthesised naphtho [2,1- b] furan derivatives. 3-nitro-2-acetylnaphtho[2,1-b]furan, 3-nitro-2-acetylnaphtho[2,1-b] furanhydrazone, Ethyl-3-aminonaphtho[2,1b]furan-2-carboxylate, Ethyl-3-(2,5-dimethylpyrrole naphtho[2,1-b]furan-2-carboxylate, 3-(2,5-dimethylpyrrole naphtho[2,1b]furan-2-carboxyhydrazide were synthesised from 2-hydroxy-1- naphthaldehyde. The structure of these compounds was confirmed by analytical, IR and 1H NMR spectral data. The above compounds were evaluated for their antioxidant activity by reducing power and DPPH methods. In reducing power the percentage of inhibition of naphtho [2,1- b] furan derivatives 1,2 and 3 were found 86.66%, 87.34% at 150 μg/ml and 85.18% at 125 μg/ml, similarly in DPPH 90.20%, 86.7% at 150 μg/ml and 84.4% at 125 μg/ml and respectively. These results suggest that the antioxidant effect of naphtho [2,1- b] furan derivatives as a powerful source used for suppression of pimples.


Shashikala Devi K.,Maharanis Science College for Women | Ramaiah M.,NMKRV College for Women | Vanita G.K.,Maharanis Science College for Women | Veena K.,NMKRV College for Women | Vaidya V.P.,Kuvempu University
Journal of Chemical and Pharmaceutical Research | Year: 2011

The required starting material 3-nitronaphtho[2,1-b]furan-2-carhohydrazide 1 was synthesized from ethy1 3-nitronaptho[2,1-b]furan-2-carboxylate. The compound 1 on reaction with carbon disulphide and hydrazine hydrate in presence of alkali produced the key intermediate 3-nitro-4-amino-5-naphtho[2,1-b]furan-2-y1-4H-1,2,4-triazole-3-thiol 2. 1,3,4-Thiadiazole moiety was constructed on triazole ring system by adopting three different experimental protocols to obtain 3-nitronaphtho[2,1b]furan-2-yl-5H-[1,2,4]triazolo[3,4-b][1,3,4]thiadiazole-6(5H)-thione 4, 3-nitronaphtho[2,1-b]furan-2-yl-6-aryl-5,6-dihydro[1,2,4 triazolo[3,4-b][1,3,4]thiadiazoles 5(ad). and 3-nitronaphtho[2,1-b]furan-2-yl-6-aryl[1,2,4]triazolo[3,4-b][1,3,4]thiadiazoles 6(a-c). To investigate the synthetic utility of compound 2 in the synthesis of bridge head six membered heterocycles, it was treated with chloroacetic acid and sodium acetate in ethanol. This reaction furnished 3-nitronaphtho[2,1-b]furan-2-y1-5H-[1,2,4]triazolo [3,4-b][1,3,4]thiadizin-6(7H)-one 3. The newly synthesized compounds were characterized by analytical and spectral studies. All the compounds were evaluated for analgesic activity by acetic acid induced writhing method by using Swiss albino mice.


Hema M.R.,NMKRV College for Women | Ramaiah M.,NMKRV College for Women | Vaidya V.P.,Kuvempu University | Shivakumar B.S.,NMKRV College for Women
Research Journal of Pharmaceutical, Biological and Chemical Sciences | Year: 2011

Artocarpus integrifolia is an important medicinal plant belonging to Artocarpus Genus (family Moraceae) is distributed over tropical and sub tropical regions. Various parts of this plant species have been used to cure ailments like inflammation, skin diseases, boils, fever, diarrhea etc. In the present study methanol extract of root bark of this plant has been evaluated for antidiabetic and antitubercular activities. Two compounds homopterocarpin and cycloheterophyllin have been isolated from methanol extract. This is the first time homopterocarpin has been isolated from Artocarpus genus. The α-amylase inhibition was assayed by adapting modified dinitrosalicylic acid method of Bernfeld to assess the antidiabetic activity. Antitubercular activity was evaluated against Mycobacterium tuberculosis H37Rv using microplate Alamar Blue(MABA) Assay method. Present study revealed that methanol extract of root bark of A. integrifolia was found to have highest inhibiting effect on α-amylase (25.2 % at 100μ g/ml) and also inhibited the growth of M. tuberculosis H37Rv (MIC 6.25μg/ml). The compounds isolated viz., homopterocarpin and cycloheterophyllin, from the root bark of this plant, showed low inhibition activity against α- amylase and did not control the H37Rv bacterial growth at low concentrations. This investigation revealed that the methanol extract of root bark of A. integrifolia has the potential to be developed further in to natural antidiabetic and antitubercular drug.


Nagaraju D.H.,National University of Singapore | Kuezma M.,National University of Singapore | Suresh G.S.,NMKRV College for Women
Journal of Materials Science | Year: 2015

One of the challenges in incorporating reduced graphene oxide (rGO) in energy storage material is to synthesize the homogenized mixtures of rGO with the electrode active materials at molecular level. In this direction, we have synthesized flexible, thin sheets of rGO-wrapped LiFePO4 plates using aqueous GO solution and precursors of LiFePO4. The in situ rGO provides necessary conductivity required for the charge storage performance. The LiFePO4/rGO composite was used as a active material without using any conductive carbon additive. The composite could be able to deliver the energy as high as about 161 mAh/g at C/10 rate and posses good cyclability. The high energy storage capabilities of LiFePO4 is due to the wrapping of highly conductive thin rGO sheets, which increases the electronic conductivity of the LiFePO4. © 2015, Springer Science+Business Media New York.


Prasannakumar S.,M.R.Research | Manjunatha R.,M.R.Research | Nethravathi C.,Materials Research Group | Suresh G.S.,M.R.Research | And 3 more authors.
Portugaliae Electrochimica Acta | Year: 2012

A modified electrode is fabricated by the electrodeposition of polyaniline-polystyrene sulphonate composite onto the carboxylated graphene modified graphite electrode for the detection of hydrogen peroxide (H2O2). The modified electrode displayed excellent catalytic response to the reduction of hydrogen peroxide in neutral pH. It was found that the presence of carboxylated graphene in the sensor system could effectively increase the electron transfer rate and stability. The modified electrode was characterized by cyclic voltammetry, electrochemical impedance spectroscopy and atomic force microscopy. Chronoamperometric studies showed the linear relationship between the reduction peak current and the concentration of H2O2 in the range 25 to 350 μM (R = - 0.995) with the detection limit of 1×10-6 mol/L (S/N=3). Further, electrochemical analysis of H2O2 in the presence of common interferents such as dopamine, uric acid and ascorbic acid with the modified electrode reveals that there is no overlapping signal from the interferents.


Devi K.S.,Maharanis Science College for Women | Ramaiah M.,NMKRV College for Women | Roopa D.L.,NMKRV College for Women | Vaidya V.P.,Kuvempu University
E-Journal of Chemistry | Year: 2010

Ethyl-3-nitronaphtho[2,1-b]furan-2-carboxylate (2) has been synthesized from ethyl naphtha [2,1-b]furan-2-carboxylate (1). This nitro product on reaction with hydrazine hydrate formed 3-nitronaphtho [2,1-b] furan-2-carbohydrazide (3). Various Schiff bases 3-nitro-N1(aryl- methylene)-substituted-naphtho [2,1-b]furan- 2-carbohydrazides 4(a-g) were obtained by treating hydrazide (3) with different aldehydes. These Schiff bases on reaction with chloro acetyl chloride in presence of triethylamine in dioxane yielded 3-nitro-N-(3-chloro-2-oxo-substituted-phenylazetidine- 1-yl) naphtha [2,1-b]furan-2-carboxamides 5(a-g). All the newly synthesized compounds have been characterized by spectral and analytical studies. The Schiff bases, 4a-g and azetidione derivatives, 5a-g have been studied for antioxidant and antimicrobial activities.


Nagaraju D.H.,Linköping University | Suresh G.S.,NMKRV College for Women
ECS Electrochemistry Letters | Year: 2012

In this article, we have demonstrated the synthesis of palladium nanoparticles decorated on reduced graphene oxide (RGO-Pd NPs) film via green chemistry route, one pot electrochemical reduction of graphene oxide and palladium ions without using any chemical reducing agents. Cyclic voltammetry in acid medium shows the characteristic nanosized palladium nanoparticles. The RGO-Pd NPs poses very high electrochemically active surface area and shows good catalytic properties for the elctrooxidation of ethanol in alkaline medium. © 2012 The Electrochemical Society.


Malingappa P.,Bangalore University | Yarradoddappa V.,NMKRV College for Women
Analytical Chemistry Insights | Year: 2014

A new chemosensor has been used to monitor atmospheric nitrogen oxides [NO + NO2] at parts per billion (ppb) level. It is based on the catalytic reaction of nitrogen oxides with rhodamine B hydrazide (RBH) to produce a colored compound through the hydrolysis of the amide bond of the molecule. A simple colorimeter has been used to monitor atmospheric nitrogen dioxide at ppb level. The air samples were purged through a sampling cuvette containing RBH solution using peristaltic pump. The proposed method has been successfully applied to monitor the ambient nitrogen dioxide levels at traffic junction points within the city limits and the results obtained are compared with the standard Griess-Ilosvay method. © the authors, publisher and licensee Libertas Academica Limited.

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