80632-27-5Relevant articles and documents
4- BROMO - 5 - (2- CHLORO - BENZOYLAMINO) - 1H - PYRAZOLE - 3 - CARBOXYLIC ACID AMIDE DERIVATIVES AND RELATED COMPOUNDS AS BRADYKININ B1 RECEPTOR ANTAGONISTS FOR THE TREATMENT OF INFLAMMATORY DISEASES
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Page 174, (2008/06/13)
Disclosed are compounds of formula I and II that are bradykinin B1 receptor antagonists and are useful for treating diseases, or relieving adverse symptoms associated with disease conditions, in mammals mediated by bradykinin B1 receptor. Certain of the compounds exhibit increased potency and are also expected to exhibit increased duration of action.
General Base Catalysis, Structure-Reactivity interactions, and Merging of Mechanisms for Elimination Reactions of (2-Arylethyl)quinuclidinium Ions
Gandler, Joseph R.,Jencks, William P.
, p. 1937 - 1951 (2007/10/02)
Structure-reactivity parameters and interaction coefficients are reported for elimination reactions of N-(2-arylethyl)quinuclidinium ions and for 2-arylethyl halides and tosylates in 60percent Me2SO/wares at 40 deg C, based on direct measurements of Bronsted β values for general base catalysis by oxyanion buffers, Hammet ρ values, and β1g for substituted quinuclidines.The Bronsted slopes increase from β - 0.67 for N-(2-(p-nitrophenyl)ethyl)quinuclidinium ions, which react by an E1cBirr mechanism, to β ca. 0.9 for the reactions of other N-(2-arylethyl)quinuclidinium ions by a concerted E2 elimination.There is no detectable interaction between the base catalyst and the leaving group for E1cB elimination, so that the interaction coefficient pxy = dβ1g/dpKBH = dβ/dpK1g is ca.0 for the N-(2-(p-nitrophenyl)ethyl)quinuclidinium ions.In contrast, values of β1g become less negative with increasing pKa of the base catalyst for the p-cyano and other N-(2-arylethyl)quinuclidinium ions, giving a constant value of pxy = 0.018 for the E2 elimination reactions of these compounds.The positive pxy coefficient for the N-(2-phenylethyl)quinuclidinium ions is confirmed by the observation of less negative values of β1g as the effective basicity of aqueous tetramethylammonium hydroxyde is increased by the addition of Me2SO.An increase in β with poorer leaving groups in the series of 2-(p-nitrophenyl)ethyl halides also corresponds to a positive pxy coefficient and an E2 mechanism.The interaction between the leaving group and central atoms is shown by the less negative values of β1g with electron-withdrawing substituents on the β-phenyl group, which corresponds to a negative coefficient pyy' = -dβ1g/d?- = -dρ/dpK1g = -0.09.A small decrease in β with electron-withdrawing substituents on the β-phenyl group suggests an interaction between the base catalyst and the central atoms that is described by a negative coefficient pxy' = dβ/d?- = dρ/dpKBH = -0.07.The sign of the pyy' and pxy' coefficient are consistent with an important component of proton transfer in the transition state.These properties of the E2 elimination reactions of N-(2-arylethyl)quinuclidinium ions can be described by a reaction coordinate that is rotated 24 deg counterclockwise from the x coordinate (for proton transfer) on a reaction coordinate-energy diagram that is defined by the observed structure-reactivity parameters.In contrast, β increases with increasing ? for elimination reactions of 2-arylethyl bromides with a positive value of pxy' = 0.07.This suggests more diagonal character to the transition state on the reaction coordinate diagram.The change from E1cB to an E2 mechanism is more easily described as a transformation of mechanism than as a change between two coexisting mechanisms.
