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31.
32.
Sridhar Madabhushi Kondal Reddy GodalaRaveendra Jillella Kishore Kumar Reddy MalluNarsaiah Chinthala 《Tetrahedron letters》2014
The synthesis of highly functionalized 2,3-dihydroisoxazoles by a one-pot multicomponent reaction of an aldehyde, hydroxamic acid, and malononitrile or methyl cyanoacetate is described. 相似文献
33.
34.
B.V. Subba Reddy Govindaraju Karthik Tamilselvan Rajasekaran Aneesh Antony B. Sridhar 《Tetrahedron letters》2012,53(19):2396-2401
A rhodium(II) catalyzed [4+2]/[2+2] cycloaddition reaction of N-protected isatin-3-arylimine with acylketene derived from α-diazocarbonyl compounds has been achieved for the first time for the preparation of a novel class of spiro(oxindolyl)oxazinone and spiro(oxindolyl)-β-lactam derivatives. 相似文献
35.
Devappa S. Lamani Kallam. R. Venugopala Reddy Halehatty. S. Bhojya Naik Halehatty. R. Prakash Naik Ajjanna. M. Sridhar 《高分子科学杂志,A辑:纯化学与应用化学》2013,50(10):857-864
The synthesis of macrocyclic ligand, diquinolineno[1,3,7,9]tetraazacyclododecine-7, 15 (14H, 16H)-dibenzene(L), is described. The metal complexes of the type [MLX2], where (M = Co(II) (1), Cu(II) (2) and X = (Cl), have been synthesized by the reaction of ligand(L) with the corresponding metal salts, and characterized by elemental analysis, FT-IR, 1H-NMR and electronic spectra. The binding property of the complexes with CT-DNA was studied by absorption spectra, viscosity measurements, as well as thermal denaturation studies. The absorption spectral results indicate that the complexes (1) and (2) are binds with base pairs of DNA. The intrinsic binding constant Kb had the value 3.8 × 104M ?1 for (1) and 3.3 × 104 M?1 for (2), respectively, in 5 mM Tris-HCl/50 mM NaCl buffer at pH 7.2. The viscosity measurement results show the viscosity of sonicated rod-like DNA fragments increased when the complex were added to the solution of calf thymus-DNA. The synthesized ligand and its metal complexes have been screened for antibacterial and antifungal activities. 相似文献
36.
Vethathiri Pakkirisamy Sridhar Mahadevan Surianarayanan Suthangathan Paramashivan Sivapirakasam Asit Baran Mandal 《Journal of Thermal Analysis and Calorimetry》2013,112(3):1335-1341
The objective of this article is to generate thermal decomposition data on fireworks tip mixture, a mixture used to coat the tip of fireworks, for easy ignition. This mixture has reportedly involved in triggering many accidents in fireworks industry. Different quantities of water were added to the mixture and its thermal characteristics were studied. Differential scanning calorimeter was used for screening tests and accelerating rate calorimeter was used for detailed studies in adiabatic and isothermal modes. The self-heat rate data obtained showed onset temperature for different quantity of water, at a range of 80–170 °C. The mixture with 40 % water wt/wt had onset at 80 °C in adiabatic mode. The same mixture on isoaging at 40 °C exhibited exothermic characteristics with a substantial rise in system pressure (57 bar). The heats of exothermic decomposition and Arrhenius kinetics were also computed. 相似文献
37.
Ramu Surakanti Sumalatha Sanivarapu Chiranjeevi Thulluri Pravin S. Iyer Raghuram S. Tangirala Rambabu Gundla Dr. Uma Addepally Y. L. N. Murthy Lakshmi Velide Dr. Subhabrata Sen 《化学:亚洲杂志》2013,8(6):1168-1176
An elegant reagent‐controlled strategy has been developed for the generation of a diverse range of biologically active scaffolds from a chiral bicyclic lactam. Reduction of the chiral lactam with LAH or alkylation with LHMDS to trigger different cyclization reactions have been shown to generate privileged scaffolds, such as pyrrolidines, indolines, and cyclotryptamines. Their amenability to substitution allows us to create various compound libraries by using these scaffolds. In silico studies were used to estimate the drug‐like properties of these compounds. Selected compounds were subjected to anticancer screening by using three different cell lines. In addition, all these compounds were subjected to antibacterial screening to gauge the spectrum of biological activity that was conferred by our DOS methodology. Gratifyingly, with no additional iterative cycles, our method directly generated anticancer compounds with potency at low nanomolar concentrations, as represented by spiroindoline 14 . 相似文献
38.
Prathama S. Mainkar Chirumarry Sridhar Ambadi Sudhakar Srivari Chandrasekhar 《Helvetica chimica acta》2013,96(1):99-108
The synthesis of bolaamphiphiles from unusual β‐amino acids or an alcohol and C12 or C20 spacers is described. Unusual β‐amino acids such as a sugar amino acid, an AZT‐derived amino acid, a norbornene amino acid, and an AZT‐derived amino alcohol were coupled with spacers under standard conditions to get the novel bolaamphiphiles 5 – 8 (Scheme 1), 12 and 13 (Scheme 2), and 17 and 20 (Scheme 3). Some of these compounds, on precipitation from MeOH/H2O, self‐assembled into organized molecular structures. 相似文献
39.
Krishnaiah Atmakur Narender Reddy Emmadi Sridhar Balasubramanian 《Journal of heterocyclic chemistry》2013,50(3):513-518
A series of novel fluorinated 11H‐azaindolo[3,2‐c]isoquinolines ( 7 ) have been synthesized starting from 2(1H)pyridones ( 1 ) via azaindoles ( 5 ). Initially, compound 1 was treated with POCl3/DMF, and the resulting compound 2 was reacted with benzylamine to obtain compounds 3 that were subjected to cyclization after protecting the secondary amine to get azaindoles ( 5 ). Further, compounds 5 were subjected to cyclization as per Pictet–Spengler reaction condition. However, it was not successful. Subsequently, the azaindoles ( 5 ) were acetylated and then cyclized to give title compounds 7 . These compounds are new and well characterized by spectral data. 相似文献
40.
M. S. R. Murty Rayudu Venkateswara Rao Kesur R. Ram N. Rami Reddy J. S. Yadav B. Sridhar 《合成通讯》2013,43(19):2914-2921
Zinc-mediated facile and efficient chemoselective S-alkylation of 5-aryl 1,3,4-oxadiazole-2-thiols in the presence of a catalytic amount of tetra butyl ammonium iodide was described. The reaction was performed under neutral conditions. The chemoselectivity of the alkylation was confirmed by NMR spectroscopy and x-ray crystallography. 相似文献