http://nopr.niscair.res.in/handle/123456789/2887 Search the Channel search http://nopr.niscair.res.in/simple-search http://nopr.niscair.res.in/handle/123456789/10741 Title: Microwave assisted facile and efficient synthesis of benzopyran <br/> <br/>Authors: Tripathi, A K; Koul, S; Taneja, S C <br/> <br/>Abstract: A convenient, fast and high yielding method for the preparation of 3,4-dihydrobenzopyrans has been achieved by the condensation of various acetophenones with different keto compounds in the presence of a base, assisted by microwave activation under solvent free conditions with or without use of a solid support. <br/> <br/>Page(s): 301-304 http://nopr.niscair.res.in/handle/123456789/6869 Title: Weinreb amide based building blocks for convenient access to various synthetic targets <br/> <br/>Authors: Sivaraman, B; Manjunath, B N; Senthilmurugan, A; Harikrishna, K; Singh, Aidhen Indrapal <br/> <br/>Abstract: <i>N</i>-Methoxy-<i>N</i>-methylamide, popularly known as the Weinreb amide (WA), has served as an excellent acylating agent for organolithium and/or organomagnesium reagents and a robust equivalent for an aldehyde group. The stability of the WA functionality, its ease of preparation, the scalability of its reactions and its predictable reactivity are the key features responsible for its prominent use in several synthetic endeavors by the chemists world-wide. The development of WA-based building blocks and synthetic equivalents for interesting synthons has been a long drawn pursuit initiated in nineties and through this mini-review accomplishments in this direction, with particular emphasis on the building blocks, developed recently in the last three years are summarized. <br/> <br/>Page(s): 1749-1756 http://nopr.niscair.res.in/handle/123456789/6868 Title: Synthesis and lipase-catalysed enantioselective acylation studies on ethyl 4-aryl-3,4-dihydropyrimidin-2(1<i style="">H</i>)-ones <br/> <br/>Authors: Prasad, Ashok K; Arya, Pragya; Bhatia, Sumati; Sharma, Raman K; Singh, Rishipal; Singh, Brajendra K; Eycken, Erik Van der; Singh, Rajpal; Olsen, Carl E; Parmar, Virinder S <br/> <br/>Abstract: A series of different analogs of 4-aryl-3,4-dihydropyrimidin-2(1<i style="">H</i>)-one have been synthesized and their biocatalytic resolution has been carried out using immobilized lipase CAL-L(A) (immobilized on accurel). The systematic one-step procedure is developed for the synthesis of optically enriched ethyl 4-aryl-6-methyl-3,4-dihydropyrimidin-2-one-5-carboxylates <b style="">8a</b>-<b style="">d</b> and acylated ethyl 4-aryl-6-methyl-3,4-dihydropyrimidin-2-one-5-carboxylates <b style="">9a</b>-<b style="">e</b>, <b style="">10a</b>-<b style="">e</b>, <b style="">11b</b>-<b style="">d</b> and <b style="">12a</b>-<b style="">e</b>, by the enantioselective acylation of racemic ethyl 4-aryl-6-methyl-3,4-dihydropyrimidin-2-one-5-carboxylates using CAL-L(A). <br/> <br/>Page(s): 1738-1748 http://nopr.niscair.res.in/handle/123456789/6867 Title: Synthesis and studies on antimicrobial, antiinflammatory and antiproliferative activities of heterocycles derived from 4-/5-/6-/7-nitro/5-fluoro/chloro/bromoindole-2-carbohydrazides <br/> <br/>Authors: Narayana, B; Ashalatha, B V; Raj, K K Vijaya; Sarojini, B K <br/> <br/>Abstract: Synthesis and studies on antimicrobial, antiinflammatory and antiproliferative activities of heterocycles derived from 4-/5-/6-/7-nitro/5-fluoro/chloro/bromoindole-2-carbohydrazides are discussed. 4-/5-/6-/7-nitroindole-2-carbohydrazides and 5-fluoro/chloro/bromoindole-2-carbohydrazides on treatment with acetyl acetone in methanol have resulted in 2-[(3,5-dimethyl-1<i>H</i>-pyrazol-1-yl)carbonyl]-4-/5-/6-/7-nitro-1<i>H</i>-indoles and 2-[(3,5-dimethyl-1<i>H</i>-pyrazol-1-yl) carbonyl]-5-fluoro/chloro/bromo-1<i>H</i>-indoles respectively. 4-/6-/7-nitroindole-2-carbohydrazides on treatment with CS₂/KOH in methanol have yielded 5-(4-/6-/7-nitro-1<i>H</i>-indol-2-yl)-1,3,4-oxadiazole-2-thiol and with cyanogen bromide yielded 5-(4-/6-/7-nitro-1<i>H</i>-indol-2-yl)-1,3,4-oxadiazol-2-amine. Nitroindole-2-carbohydrazides are also treated with various aromatic carboxylic acids and triethyl orthoformate yielded 2-[5-(aryl)-1,3,4-oxadiazol-2-yl]-4-/5-/6-/7-nitro-1<i style="">H</i>-indoles and 4-/6-/7-nitro-2-(1,3,4-oxadiazol-2-yl)-1<i>H</i>-indoles, respectively. Structures of the newly synthesized compounds are characterized by analytical and spectral data. <br/> <br/>Page(s): 1794-1805