1Laboratory of Electroanalytical Chemistry, Faculty of Chemistry, University of Tabriz, Zip code 51664, Tabriz, I.R. IRAN
2Laboratory of Organic Syntheses, Faculty of Chemistry, University of Tabriz, Zip code 51664, Tabriz, I.R. IRAN
The electrochemical behavior of nifedipine (I), nitrendipine(II) and their photodegradation products has been studied by employing electrochemical techniques in chloroform and in 1:4 mixture of chloroform-isopropanol using piperidinium perchlorate (PPC) as supporting electrolyte. It has been shown that I and II undergo in a 4e, 4H+ irreversible reduction reaction, while the reduction product, phenylhydroxylamine, is oxidized in a 2e, 2H+ reversible process to an unstable nitrosophenyl compound. Photodegradation of I and II by sunlight produces a nitrosophenyl derivative which is reversibly reduced to the corresponding unstable phenylhydroxylamine. No significant change is observed in electrochemical properties of drugs by passing from chloroform to chloroform-isopropanol mixture. The possibility of analysis of I and II by dp polarography is also verified.