PREPARATION AND CHARACTERIZATION OF IMINOQUINONE AND AMINOPHENOL DERIVATIVES OF COENZYME PQQ
5-Iminoquinone derivative of PQQ was easily prepared by treatment with ammonia.Reduction of the iminoquinone with methylhydrazine gave aminophenol derivative of reduced PQQ.Spectral characteristics of them are presented.
Reaction of Methoxatin and 9-Decarboxymethoxatin with Benzylamine. Dynamics and Products
The pH dependence of kinetics and products in the oxidation of benzylamine by methoxatin (1a) and 9-decarboxymethoxatin (1b) has been determined as has the pH dependence of the hydration of 1a and 1b (25 deg C in water, μ = 1.0 with KCl).The hydration equ
Rodriguez, Evelyn J.,Bruice, Thomas C.
p. 7947 - 7956
(2007/10/02)
Kinetics and Mechanism of the Oxidative Deamination of Amines by Coenzyme PQQ
Kinetic studies on the oxidative deamination of amines by coenzyme PQQ are carried out under anaerobic conditions.The reaction is first-order in the appearance of the reduced PQQ and in the total amine concentrations.A large kinetic isotope effect (kH/kD=7.24) in the oxidation of α,α-dideuteriobenzylamine indicates that the C-H bond cleavage is a rate-determining step.From the results of formation of two types of reduced PQQ (quinol and aminophenol) and low reactivities of secondary and tertiary amines, we propose the mechanism via covalent addition of the amine to the quinone followed by rate-limiting α-proton removal.