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91.
P. Rajesh P. Ramasamy 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2009,74(1):210-213
1 0 0 directed ammonium dihydrogen phosphate single crystal has been grown using the uniaxially solution-crystallization method of Sankaranarayanan–Ramasamy (SR). The size of the grown crystal is 40 mm in diameter and 50 mm in thickness. The grown crystals were characterized by UV–vis spectroscopy, Vickers hardness and dielectric studies. Comparing the 1 0 0 plane of the conventional method grown ADP crystal with 1 0 0 directed SR method grown ADP crystal, optical transparency, dielectric constant and Vickers hardness number are increased and dielectric loss is decreased in SR method grown crystal. 相似文献
92.
Ammonium metavanadate: A novel catalyst for synthesis of 2-substituted benzimidazole derivatives 总被引:1,自引:0,他引:1
Ammonium metavanadate (10 tool%) was found to be a useful catalyst for the synthesis of various 2-substituted aryl benzimidazoles. It was used as an oxidizing agent for the condensation of o-pbenylenediamine with different substituted aryl aldehydes at room temperature in ethanol. The method was proved to be simple, convenient and the product was isolated with good yields (79-91%). 相似文献
93.
Synthesis of 2-aryl-1-arylmethyl-1H-1,3-benzo[d]imidazoles by the reaction of o-phenylenediamine with substituted aromatic aldehydes in the presence of l-heptanesulfonic acid sodium salt (10 mol%) at room temperature.The reactions were performed in acetonitrile:water (8:2).The method was proved to be eco-friendly,convenient and the products were isolated with good yields (82-90%). 相似文献
94.
Rajesh N. Hegde Ragunatharaddi R. Hosamani Sharanappa T. Nandibewoor 《Colloids and surfaces. B, Biointerfaces》2009,72(2):259-265
We discovered a novel method to prepare a protein-based hydrogel, that is, a “Three-Dimensional Nanostructured Protein Hydrogel (3D NPH)”, which is composed of protein–polymer hybrid nanoparticles. In this study, we propose a novel protein microarray whose 3D NPH spots were prepared by dispensing a small volume of the solution of protein–polymer mixture on a substrate. The dispensed solution had a short time for cross-linking before its drying-up and the resulting 3D NPH had loosely cross-linked, thin spongy structure. Therefore, the reaction ratio between ligands and analytes was drastically improved in this system compared with the large volume system for Surface Plasmon Resonance (SPR) protein microarray. 相似文献
95.
Rajesh S. Murthy Sivaramakrishnan Muthukrishnan Sridhar Rajam Sarah M. Mandel Bruce S. Ault Anna D. Gudmundsdottir 《Journal of photochemistry and photobiology. A, Chemistry》2009,201(2-3):157-167
Photolysis of azides 1–4 in methanol, which have a built-in intramolecular triplet sensitizer, yields mainly carbamates 5–8. Laser flash photolysis of 1–4 shows formation of their triplet-excited ketone, which decays by intramolecular energy transfer to form triplet nitrenes 1n–4n. Irradiating 1–3 in matrices yields isocyanic acid, whereas photolysis of 4 forms isocyanate 4i. The depletion rate of the azide bands between 2100 and 2200 cm?1 is different than the rate of formation for the isocyanic acid bands at ~2265 cm?1; thus, the formation of isocyanic acid is a stepwise process. Irradiating 1 in matrices produces an absorption band due to nitrene 1n (λmax ~ 343 nm), which is depleted upon further irradiation, whereas the absorption due to 4-acetyl benzaldehyde (λmax ~ 280 nm) increases with prolonged irradiation. We propose that formation of isocyanic acid in matrices must come from secondary photolysis of nitrenes 1n–3n. This mechanism is further supported by calculation, which show that the estimated transition state for 1n–4n to fall apart to yield alkoxy and cyanato radicals is only ~34 kcal/mol above the ground state of the triplet nitrenes and thus the cleavage can take place photochemically. Thus, nitrenes 1n–4n can be formed selectively, but these intermediates are highly photosensitive and undergo secondary photolysis in matrices. 相似文献
96.
97.
Patwa AN Gonnade RG Kumar VA Bhadbhade MM Ganesh KN 《The Journal of organic chemistry》2010,75(24):8705-8708
X-ray crystallographic studies of methylene linked Ferrocene-bis(thymine/uracil) conjugates Fc(T:T)(M) and Fc(U:U)(M) reveal base dependent 2-D supramolecular assemblies generated via wobble self-pairing for bis-thymine and reverse wobble self-pairing for bis-uracil conjugates, differing in architecture from the corresponding butylene spacer linked conjugates. 相似文献
98.
Sulata Kumari Sahu Rajesh Ganesan T. Gnanasekaran 《The Journal of chemical thermodynamics》2010,42(1):1-7
Standard molar Gibbs free energy of formation of ternary oxides Pb5CrO8(s), Pb2CrO5(s), and PbCrO4(s) were determined by measuring equilibrium oxygen partial pressures over relevant phase fields using manometry and solid oxide electrolyte based emf methods and are given by: 相似文献
99.
Raju Suresh Kumar Stephen Michael Rajesh Subbu Perumal Perumal Yogeeswari Dharmarajan Sriram 《Tetrahedron: Asymmetry》2010,21(11-12):1315-1327
Enantiomerically pure (R)-(1-phenylethyl)-3,5-bis[(E)-arylmethylidene]tetrahydro-4(1H)-pyridinones were synthesized for the first time, and their 1,3-dipolar cycloaddition with nitrile oxides affording di- and trispiroheterocycles regio- and stereoselectively in moderate yields was investigated. These compounds were evaluated against Mycobacterium tuberculosis H37Rv (MTB) and multi-drug-resistant M. tuberculosis (MDR-TB). Among the compounds screened, the dispiroheterocycle, namely, (5R,6R,10S)-3,9-bis(4-chlorophenyl)-10-(2,4-dichlorophenyl)-14-[(E)-(2,4-dichlorophenyl)methylidene]-12-[(R)-1-phenylethyl]-1,4,7-trioxa-2,8,12-tri-azadispiro[4.0.4.4]tetradeca-2,8-diene 5m was found to possess the maximum activity with MIC of 0.49 μM against MTB, being 9.6 and 15.6 times more potent than ciprofloxacin and ethambutol, respectively. Against MDR-TB, 5m displayed maximum activity with an MIC of 0.49 μM, with it thus being more active than rifampicin, isoniazid, ciprofloxacin and ethambutol by 7.8, 23, 77 and 124 times, respectively. 相似文献
100.
Baggu Chinnababu Sudina Purushotham Reddy Chitturi Bhujanga Rao Karuturi Rajesh Yenamandra Venkateswarlu 《Helvetica chimica acta》2010,93(10):1960-1966
A simple and highly efficient stereoselective total synthesis of dodoneine ( 1 ), a naturally occurring bioactive 5,6‐dihydro‐2H‐pyran‐2‐one, was achieved. The synthesis involved Keck's asymmetric allylation, iodine‐induced electrophilic cyclization, and Grubbs' catalyzed ring‐closing metathesis as key steps. 相似文献