Kinetic study of the chlorine transfer fromN-chlorosuccinimide to amino compounds

Abstract

A kinetic study of the reactions of N-chlorosuccinimide (NCS) with glycine (Gly), sarcosine (Sar), 2-methylalanine (2MA), proline (Pro) and pyrrolidine (Pyr) was carried out. The reactions were found to be first order with respect to both NCS and the amine or amino acid and order ؊ 1 in proton concentration. In order to calculate the experimental activation parameters, the effect of temperature on the reaction rates was studied. The ionic strength and buffer concentration were found to have no effect on the rate constant. A reaction mechanism involving Cl + transfer from NCS to the amine or amino acid to form an N-chloro compound is proposed. ©

Modification of IκBα by taurine bromamine inhibits tumor necrosis factor α-induced NF-κB activation

“…In addition, it may be worth mentioning the following. The reactivity order as oxidizing agents of N-halide compounds is generally N-Br > N-Cl [46,47]. Therefore, once TauCl and TauBr enter a cell in equal amounts, it is conceivable that TauBr is more reactive than TauCl.…”

Oxidation-Controlled, Strain-Promoted Tellurophene-Alkyne Cycloaddition (OSTAC): A Bioorthogonal Tellurophene-Dependent Conjugation Reaction

“…Results in Figure a are of OSTAC performed in 10 mM NaOAc buffer, pH 5 + 0.025% Triton X-100. Citrate, acetate, phosphate, and borate buffers are found to be compatible with OSTAC; amine buffers were avoided due to the possibility of free amines being chlorinated by NCS. − The increased proportion of free amines in the biological sample at high pH and their competition against TePhe for reaction with NCS may be one reason for poorer overall performance of OSTAC under basic conditions (Figure S19d).…”

Mechanism for the reactions of sulfides with hypochlorous acid and N‐chlorosulfon‐amides: Formation of solvated chlorosulfonium cation and λ4‐sulfane intermediates

“…Therefore, one can conclude that, in contrast with the reactions of sulfides with HOCl, [25] the reactions of sulfides with N-chlorosulfonamides do not proceed with the S N 2 mechanism, presented on Scheme 4. N-chloroamides are widely used chlorinating agents [11,35,36] ; the chlorine transfer reactions to sulfides [1,[9][10][11][12][13][14] and amines [37][38][39][40] have been thoroughly investigated. The chlorine potential of N-chlorosulfonamides increases with the increasing acidity of the protons of parent amides (MsNH − << MsNH 2 < < MsNHCl).…”