http://nopr.niscair.res.in/handle/123456789/310 Search the Channel search http://nopr.niscair.res.in/simple-search http://nopr.niscair.res.in/handle/123456789/474 Title: Synthesis of novel 1,2,4-oxadiazole heterocyclic compounds containing 2-H pyranopyridine-2-one moiety and related compounds <br/> <br/>Authors: Kumar, N Vasanth; Mashelker, Uday C <br/> <br/>Abstract: 7-Hydroxy/Amino-5-methyl-6-(5-substituted-[1,2,4]oxadiazol-3-yl)-2-oxo-2H-pyrano[2,3-b]pyridine-3-carboxylic acid amides 5a-c and 6a-c have been prepared starting from ethyl 2H-pyrano [2,3-b] pyridine-3-carboxylate 1 and 2, compounds 1 and 2 are treated with aqueous ammonia solution to afford 2H-pyrano[2,3-b] pyridine-3-carboxamide 3a-b, which are converted to 6-carboxamidoxime 2H-pyrano [2,3-b] pyridine-3-carboxamide 4a-b by treating with hydroxyl amine in refluxing ethanol. Carboxamidoximes 4a-b are treated with various acid chlorides to obtain 1,2,4-oxadiazole derivatives 5a-c and 6a-c. Carboxamide 3a is reacted with triethyl orthoformate to give 4-amino-5-methyl pyrano [3",2':5,6] pyrido [2,3-d] pyrimidine-7-carboximde 7. Carboxamidoxime 4a is allowed to react with N,N-dimethyl formamide dimethyl acetal under reflux to obtain N-(6-carbonyl-4-methyl-7-oxo-1,7-dihydropyrano[2,3-b]pyrazolo[4,3-e]pyri¬dine-3-yl)methanamide 8. These compounds are expected to have better hypertensive activity. <br/> <br/>Page(s): 216-220 http://nopr.niscair.res.in/handle/123456789/472 Title: A novel synthesis of spiroisoxazoles via 1,3-dipolar cycloaddition of nitrile oxide to 6-arylidene 6,7,8,9- tetrahydrobenzo¬cyclohepten-5-one <br/> <br/>Authors: Venkateswarlu, Peesapati; Vasireddy, Nageswara Rao <br/> <br/>Abstract: Synthesis of a series of spiroisoxazole derivatives have been accomplished in good yield by regioselective 1,3-dipolar cycloaddition of nitrile oxide to 6-arylidene-3-methyl-6,7,8,9-tetrahydro-5H-benzo[a]cyclohepten-5-one. The antimicrobial activity of these compounds have been carried out. <br/> <br/>Page(s): 213-215 http://nopr.niscair.res.in/handle/123456789/471 Title: Microwave-assisted facile synthesis of a new class of asymmetrical diheteroarylmethanes bearing imidazopyridine moieties under solvent-free condition <br/> <br/>Authors: Duan, Guiyun; Sun, Yawei; Liu, Junzhi; Zhao, Guilong; Zhang, Datong; Wang, Jianwu <br/> <br/>Abstract: Microwave-assisted facile condensation of ethyl 2-benzimidazoleacetates or ethyl 2-benzothiazoleacetates with o-diaminopyridines under solvent-free condition has afforded asymmetric diheteroarylmethanes in excellent yields. The synthetic route is optimized and all the reported compounds are fully characterized. <br/> <br/>Page(s): 210-212 http://nopr.niscair.res.in/handle/123456789/469 Title: Microwave assisted synthesis of N-(3-aryl-1,8-naphthyridin-2-yl) phthalimides under solvent-free conditions <br/> <br/>Authors: Mogilaiah, K; Sakram, B <br/> <br/>Abstract: A simple, rapid and efficient protocol for the synthesis of N-(3-aryl-1,8-naphthyridin-2-yl)phthalimides 3 has been achieved by the reaction of 2-amino-3-aryl-1,8-naphthyridines 1 with phthalic anhydride 2 in the presence of catalytic amount of DMF under microwave irradiation. <br/> <br/>Page(s): 207-209