In-vitro studies of two 5-nitroimidazole derivatives.

This paper reports the findings obtained using two new compounds belonging to the 5-nitroimidazole family: sulphuridazole (V1) and sulphonidazole (V2). We first assessed their antimicrobial activity on Clostridia spp. and then extended the study to Gram-positive and Gram-negative aerobic microorganisms and to Candida albicans. Their MICs were compared with those of metronidazole. The findings show that the antibacterial and antimycotic activity of sulphonidazole is greater than that of sulphuridazole, while metronidazole is not active against any aerobic organism. It also emerges that the NO2 group is indispensable for all the microorganisms assayed and that sulphuridazole and sulphonidazole are the first two 5-nitroimidazoles active against C. albicans. The redox potentials of the 5-nitroimidozoles studied suggest that their action mechanism is mainly based on redox processes.