Nucleophilic reactivity of thiolate, hydroxide, and phenolate ions toward a model<i>O</i><sup>2</sup>-arylated diazeniumdiolate prodrug in aqueous and cationic surfactant media
作者:Matthew S. Ning、Stacy E. Price、Jackie Ta、Keith M. Davies
DOI:10.1002/poc.1607
日期:——
and in solutions of cationic DOTAP vesicles. Second-order rate constants in buffered aqueous solutions (k(RS(-) ) = 3.48 - 30.9 M(-1)s(-1); 30 degrees C) gave a linear Bronsted plot (beta(nuc) = 0.414 +/- 0.068) consistent with rate-limiting S(N)Ar nucleophilic attack by thiolate ions. Cationic DOTAP vesicles catalyze the thiolysis reactions with rateenhancements between 11 and 486-fold in Tris-HCl
The present invention provides, in part a novel class of nonoate compounds which exhibit nitric oxide releasing activity and their pharmaceutically acceptable salts, esters and prodrugs. The compounds release nitric oxide upon activation by contact with plasma. The present invention also relates to the use of the disclosed compounds to deliver nitric oxide to treat disorders arising from nitric oxide dysregulation.
libraries generated against the tert-butyl phosphonatehapten 2 and the chloromethyl phosphonatehapten 3 with pivaloyloxymethyl-umbelliferone 1 as a fluorogenic substrate led to the isolation of eleven catalyticantibodies with rate accelerations around kcat/ kuncat = 10(3). The antibodies are not inhibited by the product and accept different acyloxymethyl derivatives of acidic phenols as substrates. The
d NO donor with an in-built fluorescencereporter. We demonstrate that this compound is capable of enhancing NO within cells in a dose-dependent manner, accompanied by a similar increase in fluorescence. The compatibility of this tool to study NO-mediated signalling as well as NO-mediated stress is demonstrated. FLUORO/NO is a convenient tool that shows NO-like activity and allows monitoring of NO
The Secondary Amine/Nitric Oxide Complex Ion R<sub>2</sub>N[N(O)NO]<sup>-</sup> as Nucleophile and Leaving Group in S<sub>N</sub>Ar Reactions
作者:Joseph E. Saavedra、Aloka Srinivasan、Challice L. Bonifant、Jingxi Chu、Anna P. Shanklin、Judith L. Flippen-Anderson、William G. Rice、Jim A. Turpin、Keith M. Davies、Larry K. Keefer
DOI:10.1021/jo0016529
日期:2001.5.1
the cis arrangement of the oxygens were confirmed by X-ray crystallography. Displacement by various nucleophiles showed R(2)N[N(O)NO](-) to be a reasonably good leaving group, with rate constants for displacement by hydroxide, methoxide, and isopropylamine that were between those of chloride and fluoride in the S(N)Ar reactions we surveyed. The Meisenheimer intermediate could be spectrally observed. These