- Mechanistic Insights of a Concerted Metalation-Deprotonation Reaction with [Cp?RhCl2]2
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The effect of the carboxylate used in a concerted metalation-deprotonation reaction is probed and shows a direct correlation of pKa to observed rate up to a pKa of 4.3, where the rate drops off at higher pKa. The rate of the C-H activation of 2-(4-methoxyphenyl)pyridine with [Cp?RhCl2]2 and carboxylate follows first-order kinetics in the active metal species, Cp?RhCl(2-OAc), and zero-order kinetics in substrate when in a 1:1 ratio. There is a first-order dependence on substrate observed when excess substrate is present. The evaluation of the mechanism using kinetic studies allowed for a mechanistic proposal in which a second Ph′Py coordinates prior to the rate-determining C-H activation.
- Walsh, Aaron P.,Jones, William D.
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Read Online
- SUBSTITUTED PYRIMIDINES
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Disclosed are substituted pyrimidines useful as HIF prolyl hydroxylase inhibitors to treat anemia and like conditions.
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Page/Page column 87
(2013/04/10)
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- SUBSTITUTED PYRIMIDINES
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The present invention relates to substituted pyrimidines useful as HIF prolyl hydroxylase inhibitors to treat anemia and like conditions.
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Page/Page column 87; 88
(2013/04/10)
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- Spectrophotometric and spectrofluorimetric determination of fluorouracil in the presence of its degradation products
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Three reliable spectrophotometric and spectrofluorimetric procedures are described for the determination of fluorouracil in bulk powder and ampoules in the presence of its degradation products. One spectrophotometric procedure, based on measurement at 555 nm of the violet-coloured complex formed by fluorouracil with cobalt(II), has a detection limit of 0.03 mg mL-1. Two sensitive spectrofluorimetric procedures are also proposed. One is based on measurement of the intrinsic fluorescence of the liberated fluorouracil at 375 nm, after precipitation as its cobalt(II) complex, decomposition of the precipitate with sulphuric acid and excitation at 295nm. The second depends on excitation of the fluorouracil-cobalt(II) complex at 395 nm and measuring its fluorescence at 483 nm. The limits of detection of the two spectrofluorimetric procedures are 0.5 and 2 μg mL-1, respectively. The three procedures have been used successfully for the determination of fluorouracil ampoules. The validity of the methods has been assessed by applying the standard addition technique.
- Amer,Hassan,Abd El-Fatah,El-Kosasy
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p. 133 - 138
(2007/10/03)
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- Homogeneous, stable and flowable aqueous mixtures and dispersions of water-insoluble substances formulated therefrom exhibiting optical birefringence
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Stable and flowable aqueous dispersions of at least one water-insoluble material are formulated by dispersing such water-insoluble material, e.g., solid particulates of a plant protection compound, into a homogeneous, stable and flowable aqueous composition that includes (1) at least one water-soluble derivative of a plant protection active agent bearing at least one ionizable functional group and at least one hydrophilic functional group, (2) at least one nonionic surface-active agent and/or at least one aliphatic, cycloaliphatic or arylaliphatic alcohol having from 4 to 15 carbon atoms, and (3) water, this composition exhibiting optical birefringence and a yield point of at least 0.1 pascal.
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