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11.
Venkatapuram Padmavathi Dandu Rangayapalle Chinna Venkata Subbaiah Boggu Jagan Mohan Reddy 《Journal of heterocyclic chemistry》2005,42(2):255-258
A new class of bis Michael adducts are prepared from 1,3‐bis‐[2‐(2‐arylethenesulfonyl)‐vinyl]‐benzenes and 1,4‐bis‐[2‐(2‐arylethenesulfonyl)‐vinyl]‐benzenes by double Michael addition reaction with active methylene compounds. 相似文献
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Venkatapuram Padmavathi Akula Balaiah Dandu Bhaskar Reddy 《Journal of heterocyclic chemistry》2002,39(4):649-653
The 1,5‐diaryl‐3,3‐disubstituted‐1,5‐pentanedione on reaction with ammonium acetate, phosphorus pentoxide and phosphorus pentasulfide gave respective 1,4‐dihydropyridine, 4H‐pyran and 4H‐thiopyran. Novel spiro heterocycles have been obtained by the cyclocondensation of 4H‐thiopyran with hydrazine, hydroxylamine, urea and thiourea. 相似文献
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Venkatapuram Padmavathi Shaik Mahaboob Basha Dandu Rangayapalle Chinna Venkata Subbaiah Tippireddy Venkata Ramana Reddy Adivireddy Padmaja 《Journal of heterocyclic chemistry》2005,42(5):797-802
Novel spiro heterocycles, substituted spiro‐pyrimidine, pyrazole and isoxazole compounds are prepared by the cyclocondensation of 4‐oxocyclohexane gem‐dicarboxylates and cyano esters with nucleophiles. 相似文献
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Synthesis and Antimicrobial Activity of a New Class of Sulfonylmethane Linked Bisheterocycles 下载免费PDF全文
Padmavathi Venkatapuram Seenaiah Dandu Premakumari Chokkappagari Padmaja Adivireddy 《Journal of heterocyclic chemistry》2014,51(6):1757-1763
A new class of sulfonylmethane linked bisheterocycles were prepared and studied their antimicrobial activity. 相似文献
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Padmavathi Venkatapuram Sreelatha Tumma Seenaiah Dandu Premakumari Chokkappagari 《Journal of heterocyclic chemistry》2015,52(3):756-763
The amido‐linked oxazolyl/thiazolyl/imidazolyl pyrazoles and isoxazoles were prepared from the synthetic intermediates oxazolyl/thiazolyl/imidazolyl acrylamides adpoting1,3‐dipolar cycloaddition of nitrile imines and nitrile oxides. 相似文献
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Dandu Bhaskar Reddy Nalla Reddy Chandrasekhar Babu Venkatapuram Padmavathi 《Journal of heterocyclic chemistry》2001,38(3):769-772
The double Michael addition of dimethyl malonate to 2‐arylethenyl‐2′‐arylethynyl sulfones (3) resulted in 3,5‐diaryl‐5,6‐dihydro‐4,4‐dimethoxycarbonyl‐1‐thiin‐1,1‐dioxides (4) . The latter on cyclocondensation with urea / thiourea / hydrazine hydrate / hydroxylamine hydrochloride gave spiroheterocycles. 相似文献
18.
Kurt A. Josef Reddeppareddy Dandu Ming Tao Robert L. Hudkins 《Journal of heterocyclic chemistry》2006,43(3):719-722
This paper communicates the (regio) synthesis and a convenient NMR structural assignment method for N‐methyl‐tetrahydro‐5H‐indazol‐5‐one isomers. The cyclization reaction of 7‐(hydroxymethylene)‐1,4‐dioxaspiro[4,5]decan‐8‐one ( 3 ) with methylhydrazine yields, after de‐protection predominately the N‐2 methyl isomer 2 . Analysis of the product ratio and structural assignments are based on NMR data including NOE difference experiments and subsequently confirmed with X‐ray crystallography. These findings are in sharp contrast with the literature. The experimental conditions used to optimize the synthesis of the individual isomers are discussed. 相似文献