- The Lactam-Lactim Tautomerization of Monoamino-Substituted 2-Pyridinols in Tetrahydrofuran
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MINDO/3 calculations have been performed on 3-amino-, 4-amino-, 5-amino-, and 6-amino-2-pyridinols to estimate their molecular geometries.The lactam-lactim tautomerization from amino-2-pyridone to amino-2-pyridinol was expected for 5-amino- and 6-amino-2-pyridinols from the MINDO/3 calculations.In addition, their dimer formation energies were evaluated by the CNDO/2 method.Among the four amino-2-pyridones, 6-amino-2-pyridone has the largest dimer formation energy and 3-amino-2-pyridone the smallest.Furthermore, to certify the tautomerization of 3-amino-, 5-amino-, and 6-amino-2-pyridinols the UV absorption and fluorescence spectra were measured, and compared with those of their O-methyl and nuclear N-methyl derivatives.From the UV spectral data the equilibrium constants of the lactam-lactim tautomerization were determined for 5-amino and 6-amino derivatives in tetrahydrofuran (THF) at various temperatures.The lactam form is more stable than that of the lactim; the enthalpy changes between two forms of 5-amino and 6-amino derivatives were estimated to be 7.9 and 6.3 kJ mol-1, respectively.The lactam and lactim dimers of these two derivatives were found to be easily formed in THF and ether.From the fluorescence spectral data the lactim dimer of 6-amino derivative was found to be formed in the lowest excited ?,?* singlet state.On the other hand, the 3-amino derivative exists predominantly in the lactam monomer form in both the ground and the lowest excited ?,?* singlet states.
- Fujimoto, Akira,Inuzuka, Kozo
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- Transformation of Streptonigrin to Streptonigrone: Flavin Reductase-Mediated Flavin-Catalyzed Concomitant Oxidative Decarboxylation of Picolinic Acid Derivatives
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In the flavin-reductase-catalyzed reducing condition, a mild and efficient α-hydroxylation and decarboxylation procedure using natural flavins as a catalyst and atmospheric oxygen as an external oxidizing agent has been successfully developed and applied
- Wo, Jing,Kong, Dekun,Brock, Nelson L.,Xu, Fei,Zhou, Xiufen,Deng, Zixin,Lin, Shuangjun
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- SUBSTITUTED HYDANTOIN AND THIOHYDANTOIN DERIVATIVES AS ANDROGEN RECEPTOR ANTAGONISTS
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Disclosed are compounds, compositions and methods for treating of disorders that are affected by the antagonism of one or more androgen receptor types. Such compounds are represented by Formula (I), wherein R1, R2a, R,2b,Z
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Page/Page column 81
(2018/09/25)
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- MOF-derived Ni-based nanocomposites as robust catalysts for chemoselective hydrogenation of functionalized nitro compounds
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Porous graphitic carbon layers encapsulating Ni nanoparticles (Ni@C) were prepared by a facile thermolysis of a Ni-containing metal-organic framework, the structure of which were characterized by power X-ray diffraction (XRD), N2 adsorption-desorption, transmission electron microscopy (TEM), and X-ray photoelectron spectroscopy (XPS) in detail. The resulting Ni@C nanocomposites served as highly efficient and magnetically recyclable catalysts for the hydrogenation of diverse functionalized nitro compounds to the corresponding anilines under relatively milder conditions. The high catalytic performance and the enhanced stability are ascribed to the synergistic effects and electron transfer between the metallic Ni and graphitic carbon as well as the unique encapsulation structure. The achieved success in the MOF-derived Ni@C nanocomposites may pave the way for designing environmentally benign catalytic hydrogenation processes for industrial applications.
- Tang, Bo,Song, Wei-Chao,Yang, En-Cui,Zhao, Xiao-Jun
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p. 1531 - 1539
(2017/01/21)
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- SUBSTITUTED THIOHYDANTOIN DERIVATIVES AS ANDROGEN RECEPTOR ANTAGONISTS
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Disclosed are compounds, compositions and methods for treating of disorders that are affected by the antagonism of one or more androgen receptor types. Such compounds are represented by Formula (I) as follows: Formula (I) wherein R1 and G are defined herein.
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Page/Page column 224; 225
(2017/08/07)
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- A metal-organic framework-templated synthesis of γ-Fe2O3 nanoparticles encapsulated in porous carbon for efficient and chemoselective hydrogenation of nitro compounds
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The γ-Fe2O3 nanoparticles well dispersed in porous carbon were fabricated via a Fe-based metal-organic framework-templated pyrolysis. The resultant product exhibits excellent catalytic activity, chemoselectivity and magnetic recyclability for the hydrogenation of diverse nitro compounds under mild conditions.
- Li, Yang,Zhou, Yu-Xiao,Ma, Xiao,Jiang, Hai-Long
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supporting information
p. 4199 - 4202
(2016/03/19)
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- N -pyridyl and pyrimidine benzamides as KCNQ2/Q3 potassium channel openers for the treatment of epilepsy
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A series of N-pyridyl benzamide KCNQ2/Q3 potassium channel openers were identified and found to be active in animal models of epilepsy and pain. The best compound 12 [ICA-027243, N-(6-chloro-pyridin-3-yl)-3,4-difluoro-benzamide] has an EC50 of 0.38 μM and is selective for KCNQ2/Q3 channels. This compound was active in several rodent models of epilepsy and pain but upon repeated dosing had a number of unacceptable toxicities that prevented further development. On the basis of the structure-activity relationships developed around 12, a second compound, 51, [N-(2-chloro-pyrimidin-5-yl)-3,4-difluoro- benzamide, ICA-069673], was prepared and advanced into a phase 1 clinical study. Herein, we describe the structure-activity relationships that led to the identification of compound 12 and to the corresponding pyrimidine 51.
- Amato, George,Roeloffs, Rosemarie,Rigdon, Greg C.,Antonio, Brett,Mersch, Theresa,McNaughton-Smith, Grant,Wickenden, Alan D.,Fritch, Paul,Suto, Mark J.
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scheme or table
p. 481 - 484
(2011/08/22)
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- SUBSTITUTED PYRIDAZINE CARBOXAMIDE COMPOUNDS AS KINASE INHIBITOR COMPOUNDS
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Pyridazine derivatives have unexpected drug properties as inhibitors of protein kinases and are useful in treating disorders related to abnormal protein kinase activities such as cancer.
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(2010/01/12)
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- DERIVATIVES OF QUINOLINES AND QUINOXALINES AS PROTEIN TYROSINE KINASE INHIBITORS
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The invention relates to compounds of Formula (I), wherein the substituens are as defined in the specification, in free form or in the form of a pharmaceutically acceptable salt, solvate, ester, N-oxide thereof; processes for the preparation thereof; to p
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(2009/12/27)
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- One step hair coloring compositions using salts
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A hair coloring composition comprising the following two compositions which are mixed just prior to application to the hair: (a) a composition comprising a water-soluble peroxygen oxidizing agent; and (b) a composition comprising one or more oxidative hair coloring agents selected from the group consisting of an aromatic diamine, an amino phenol, a naphthol, a polyhydric phenol, a catechol and mixtures thereof; wherein the composition comprising one or more oxidative hair coloring agents further comprises al least one water soluble carbonate releasing salts; and optionally a water soluble ammonium salt, is described.
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- Transition metal complexes as dye forming catalysts in hair coloring compositions
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A hair coloring composition comprising a first composition which comprises: (a) a dye forming transition metal salt or complex; which is first applied to the hair; and a second composition which comprises the following two compositions which are mixed just prior to application to the hair: (a) a composition comprising a water-soluble peroxygen oxidizing agent; and (b) a composition comprising one or more oxidative hair coloring agents selected from the group consisting of an aromatic diamine, an aminophenol, a polyhydric phenol a catechol and mixtures thereof.
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- Enhanced color deposition for hair with sequestering agents
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Hair coloring compositions which comprise: (A) non-nitrogenous chelating agents from the group consisting of polyphosphate; phosphonates; hydroxycarboxylates; polyacrylates; zeolite; and mixtures thereof; (B) an oxidative dye primary intermediate; and (C) an oxidative dye coupler; (D) and water are described. The present invention also relates to a method for coloring hair which comprises contacting said hair with a hair coloring composition as described above.
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- Chroman derivative and pharmaceutical use thereof
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Chroman derivatives of the formula ?I! STR1 wherein R1 is a cyano, a nitro, a trihalomethyl, a trihalomethoxy or a halogen atom; R2 is a lower alkoxyalkyl, an aryloxyalkyl or a dialkoxyalkyl; R3 is a lower alkoxyalkyl or an aryloxyalkyl; R4 is a hydroxy, a formyloxy or a lower alkanoyloxy; X is N--H, an N--optionally substituted lower alkyl, an oxygen atom, a sulfur atom or a single bond; and Y is an optionally substituted aromatic ring residue or an optionally substituted heterocyclic residue, pharmaceutically acceptable salts thereof and pharmaceutical use thereof. The compound of the present invention and pharmaceutically acceptable salts thereof have selective and excellent coronary vasodilating action and extremely weak hypotensive action. Accordingly, it is possible to selectively increase the coronary blood flow without causing a sudden hypotention causative of tachycardia which has a detrimental effect on the heart, and they are useful as a coronary vasodilator, in particular, an agent for the prophylaxis and treatment of cardiovascular disorders such as angina pectoris and heart failure.
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