Voltammetric study of 7-nitro-1,4-benzodiazepin-2-ones and their acid hydrolysis products, 2-amino-5-nitrobenzophenones

Abstract

The electrochemical reduction of 7-nitro-I ,4-benzodiazepin-2-ones and of their acid hydrolysis products, 2-amino-5-nitrobenzophenonesf was studied by polarography and cyclic voltammetry in a solventbuffer system containing pyridine, formic acid and tetramethylammonium chloride solution in order to elucidate the effect of the nature and position of the substituents on the reduction of the nitro group. It was found that these two types of compounds can be polarographically and voltammetrically distinguished and that their reduction mechanisms differ owing to a structural change in substituents located at a para-position relative to the nitro group. Based on polarographic and cyclic voltammetric data, reduction mechanisms for these two species are proposed in which the donoracceptor properties of the substituents and the importance of the chemical reactions associated with the electron-transfer steps are indicated. Keywords: 7-Nitro -I , 4-benzo diazep in -2-one; 2 -am in o-5-n itro benzop h e n o n e; p o la rog rap h y; cyclic vo ltam -Paper 91006086

Elucidation of Degradation Behavior of Nitrazepam and Other Benzodiazepines in Artificial Gastric Juice: Study on Degradability of Drugs in Stomach (II)

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“…10) With regard to the physical properties of BZPs, it is known that the azomethine bond of the diazepine ring in many BZPs is cleaved off under acidic conditions, although ring closure occurs under neutral conditions. 10,11) These studies suggest that orally ingested BZPs are degraded in the stomach but restored to their original state in the small intestine. In addition, in the experiments based on these reports, the acidic condition for degradability verification is simply created by using dilute hydrochloric acid, and there are almost no data from in vivo research.…”

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Flow‐through polarographic cell for flow‐injection analysis. Determination of nifedipine in pharmaceutical formulations

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Study of Electrochemical Reactions Using Nanospray Desorption Electrospray Ionization Mass Spectrometry

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