Photoinduced electron transfer photodegradation of photosensitive diuretic drug-xipamide

Xipamide (1), a photosensitive diuretic drug is photolabile under anaerobic conditions and with UVA light. In the present study the photochemical behavior of xipamide was investigated in the presence of both electron donor and acceptor. When xipamide (1) was irradiated with a high-pressure mercury lamp under anaerobic conditions in the presence of electron-donor N,N-dimethyl aniline (DMA) it afforded photoproduct 2 and in the presence of an electron-acceptor 1,4-dicyanonaphthalene (DCN) it afforded photoproduct 3. The product formation was explained through the photoinduced electron transfer mechanism. Products were isolated and identified on the basis of IR, NMR and mass spectral studies.