Collect. Czech. Chem. Commun.
2004, 69, 1429-1442
https://doi.org/10.1135/cccc20041429
Polarographic and Voltammetric Behavior of the Antibiotic Cefetamet; Reduction of the Methoxyimino Group
Mara Aleksića, Vera Kapetanovićb and Petr Zumanc,*
a Department of Physical Chemistry, Faculty of Pharmacy, Vojvode Stepe 450, 11000 Belgrade, Yugoslavia
b Department of Analytical Chemistry, Faculty of Pharmacy, Vojvode Stepe 450, 11000 Belgrade, Yugoslavia
c Department of Chemistry, Clarkson University, Potsdam, NY 13699-5810, U.S.A.
Abstract
Evaluation of DC polarographic i-E curves and analogous curves obtained by cyclic voltammetry in aqueous buffers as well as in buffers containing 30% v/v ethanol indicated that the methoxyimino group of cefetamet is reduced on DME and HDME in the following way: the methoxyimino group can be at the electrode surface rapidly protonated up to pH about 9. In the protonated form of the grouping (>C=NH-OCH3)+, the OCH3 is cleaved off in the first two-electron step. The resulting imine is in equilibrium with its protonated form, which is reduced in a second two-electron step. At pH higher than about 10, the unprotonated form of the methoxyimino group is reduced in a single four-electron step to amine. Studies using cyclic voltammetry were complicated by adsorption phenomena.
Keywords: Cefetamet; Cephalosporins; Oximino group; Electroreduction; Polarography; Voltammetry; Antibiotics; Electrochemistry.
References: 13 live references.
