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51.
Sandeep Sundriyal Smriti Khanna Rikta Saha Prasad V. Bharatam 《Journal of Physical Organic Chemistry》2008,21(1):30-33
This theoretical study attempts to find out similarity between metformin and glitazone class of antidiabetic drugs. It was found that some tautomeric forms of both metformin and thiazolidinedione ring of glitazones have similar molecular electrostatic potential (MESP) surface and may bind to a common complementary surface. Complexation and docking studies were also carried out in order to support this hypothesis. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
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Fadhil S. Kamounah Liudmil Antonov Vesselin Petrov Gert van der Zwan 《Journal of Physical Organic Chemistry》2007,20(5):313-320
The aim of the current report is to shed light on the tautomerism of 4‐((Phenylimino)methyl) naphthalene‐1‐ol in solution, which was studied by UV–Vis spectroscopy and quantum chemical calculations. It was found that this compound does not have the typical tautomeric behavior of its analog 4‐Phenylazo‐naphthalen‐1‐ol. The complicated equilibrium between the enol‐ and keto‐like forms and two kinds of dimers that can exist in solution, is strongly dependent on the proton acceptor/donor abilities of the solvent. Using advanced data treatment quantitative information about the tautomeric and dimeric equilibrium constants was obtained. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
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Influence of dibenzoylmethane's substituents in meta and para positions on chemical shift values of tautomers' characteristic protons was investigated in four solvents with 1H NMR spectroscopy: acetone‐d6, benzene‐d6, CDCl3 and deuterated dimethyl sulfoxide (DMSO‐d6). It was proved that the influence of substituents on chemical shifts strongly depends on the kind of the solvent; the greatest changes were observed in benzene‐d6 and the smallest in CDCl3. In acetone‐d6 and DMSO‐d6, the influence of substituents on chemical shifts is similar and the most regular. It allowed a fair correlation of chemical shifts of para‐substituted dibenzoylmethane derivatives' characteristic protons with Hammett substituent constants in these solvents. In CDCl3, characteristic protons' chemical shifts were near 1H NMR spectroscopy measurement error limits, and, therefore, correlation with Hammett substituent constants in this solvent was unsatisfactory. In benzene, although the changes of chemical shifts are the most evident, the changes are also the most irregular, and, therefore, correlation in this solvent failed completely. Results of meta‐substituted derivatives were much more irregular, and their correlation with Hammett substituent constants was poor in all investigated solvents. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
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Karnaukhova R. V. Nizovtseva T. V. Nakhmanovich A. S. Albanov A. I. Komarova T. N. 《Russian Chemical Bulletin》2001,50(12):2475-2476
Reactions of 1-aroyl-2,2-dimethylhydrazines with 1,3-dibromopropyne in MeOH or MeCN at 20—50 °C yield 2-aryl-6-bromomethylidene-4,4-dimethyl-5H-1,3,4-oxadiazinium bromides. 相似文献
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Hong Ping LI Hai Fei ZHANG Jun LIU Bu Xing HAN* Center for Molecular Sciences Institute of Chemistry Chinese Academy of Sciences Beijing 《中国化学快报》2001,(4)
There are some unique advantages for chemical reactions in SCFs. For example, reaction rates, yields, and selectivity can be tuned by pressure or small amount of cosolvent. SCFs can be used to replace environmentally undesirable solvents. It is not surprised that in recent years the use of SCFs as solvents for chemical reaction media has received much attention. However, mechanism for the effect of pressure and cosolvents on chemical reactions is not very clear. Tautomeric reactions are id… 相似文献
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