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101.
102.
Ravindra D. Jadhav Hitesh D. Mistry Hashim Motiwala Kishorkumar S. Kadam Shivaji Kandre Amol Gupte Ashok K. Gangopadhyay Rajiv Sharma 《Journal of heterocyclic chemistry》2013,50(4):774-780
Hydroxy (tosyloxy) iodobenzene (HTIB), a hypervalent iodine reagent, has been extensively used for oxidative transformations. We have developed a one‐pot synthesis wherein aldoximes when reacted with alkynes in the presence of HTIB result in the direct formation of isoxazoles. This simple and straightforward reaction allows for ease of purification while leading to the formation of high purity 3,5‐disubstituted isoxazoles in moderate yields. 相似文献
103.
Sanjay A. Jadhav Shashikant B. Landge Samadhan S. Shelke Navanath C. Niphade Raghavendra K. Panchangam Vijayavitthal T. Mathad Saroj R. Bembalkar 《Chromatographia》2010,71(11-12):1055-1061
A rapid and sensitive gas chromatographic method using flame ionization detection (GC–FID) has been developed and validated for five process related non-chromophoric impurities viz, 2-(2-chloroethoxy)ethanol (2-CEE), piperazine, 2-(piperazin-1-yl)ethanol (HEP), 2-[2-(piperazin-1-yl)ethoxy]ethanol (HEEP), 2,2-[piperazine-1,4-diylbis(ethane-2,1-diyloxy)]diethanol (DEEP) observed during the process development of quetiapine hemifumarate, an antipsychotic drug is presented. All five non-chromophoric impurities ranging from 0.05 to 0.1% were detected using DB-5 (30 m × 0.53 mm, 5 μm) column with a good peak separation. The method was fully validated according to the ICH Q2 (R1) guidelines. The investigated validation protocols showed that the method has acceptable specificity, accuracy, linearity, precision, robustness and high sensitivity with detection limits and quantitation limits ranging from 0.001 to 0.01% and 0.004 to 0.03%, respectively. These non-chromophoric impurities generated during the process were identified by GC–MS and are characterized by MS, 1H NMR and FT-IR spectroscopy. 相似文献
104.
A. V. Karnik N. J. Malviya A. M. Kulkarni D. Jaimini B. L. Jadhav 《Journal of heterocyclic chemistry》2006,43(2):489-493
Chemoselective synthesis of novel hetero cyclopenta[b]chrysene derivatives, namely, 6‐Aryl‐2,2a‐dihydro‐naphtho[2′,1′‐5,6]pyrao[4,3‐e][1,2,4]triazolo[3,4‐b][1,3,4]thiadiazine ( 4a‐j ) under neutral condition has been described. These molecules exhibited good to excellent anti‐bacterial activities. 相似文献
105.
106.
S. R. Sarda W. N. Jadhav N. B. Kolhe M. G. Landge R. P. Pawar 《Journal of the Iranian Chemical Society》2009,6(3):477-482
α-β-Unsaturated carbonyl compounds on condensation with o-phenylenediamine in the presence of catalyst sulfamic acid under solvent free conditions, resulted in the formation of corresponding benzo-[b]-1,4-diazepines in excellent yields. 相似文献
107.
The substituted warfarin acid chalcones have been prepared by condensation of warfarin acid and aromatic/aliphatic aldehyde using aq. NaOH as catalyst. The method is simple, cost‐effective and gives good yield in a short reaction time. All the compounds synthesized have been characterized by IR, NMR and Mass spectra. A new series of 4‐hydroxy‐3‐(3‐oxo‐1,5‐diaryl‐3‐oxo‐pent‐4‐enyl)‐chromen‐2‐ones were synthesized and submitted to biological activity. Result of the biological screening showed the compounds 3b , 3h being the most effective among the various treatments in antimicrobial screening. Compounds 3c , 3d , 3k and 3l showed moderate activity against the microorganisms tested. Compounds 3e , 3h have shown good antifungal activity. 相似文献
108.
Vrushali H. Jadhav Omprakash P. Bande Vedavati G. Puranik Dilip D. Dhavale 《Tetrahedron: Asymmetry》2010,21(2):163-170
The Sharpless asymmetric epoxidation of d-glucose-derived allyl alcohol 4 afforded α- and β-epoxides 5a and 5b in high stereoselectivity. The epoxide ring opening in 5a/5b was studied with different nucleophilic azido reagents, under various reaction conditions, and was found to be highly regioselective to give the preferential formation of 6-azido diol 6a/6b over 5-azido-diol 7a/7b. The 6-azido diol 6a/6b and 5-azido diol 7a/7b thus obtained were converted to the corresponding seven- and six-membered iminosugar, namely, azepane 1a/1b and 1-deoxy-nojirimycin 2a/2b. 相似文献
109.
Some new 3,5‐diphenyl and 1,3,5‐triphenyl‐2‐pyrazolines derivatives were synthesized by reacting 1,3‐diphenyl‐2‐propen‐1‐ones with hydrazine hydrates and phenyl hydrazine in ethanol. The structural elucidation of the compounds was performed by IR, 1H NMR and elemental analysis. All examined compounds showed appreciable antibacterial activity. 相似文献
110.
A rapid, selective and simple method has been developed for the determination of Sc in rock samples by thermal neutron activation analysis, employing substoichiometric solvent extraction of Sc(III) with alizarin into 1-octanol. Two samples and a standard can be processed and counted within three hours. 相似文献