Metronidazole

Metronidazole is a nitroimidazole drug similar to tinidazole (see Chapter 100, Tinidazole). It has the chemical formula 1-(2-hydroxyethyl)-2-methyl-5-nitroimidazole, the empirical formula C₆H₉N₃O_3, and a fairly low molecular weight, 171.15 kDa (see Figure 99.1). Following the discovery that azomycin, a nitroimidazole drug isolated from a Streptomyces species, was weakly active against Trichomonas vaginalis, many similar drugs were synthesized at the Rhône-Poulenc Research Laboratories in France. One of these, metronidazole, was very active against experimental T. vaginalis infections (Cosar and Julou, 1959), and was soon shown to be useful for the systemic treatment of urogenital trichomoniasis in humans (Durel et al., 1959). Animal studies suggested that it may also be useful in the treatment of amebiasis in humans (Cosar et al., 1961), and this was subsequently confirmed in human studies (Powell et al., 1966). In addition, it was demonstrated to be effective against human Giardia lamblia infections (Schneider, 1961). Figure 99.1 Structure of metronidazole. https://s3-euw1-ap-pe-df-pch-content-public-p.s3.eu-west-1.amazonaws.com/9781315152110/08d8042d-9481-4a8d-8c27-9bd589f6de6b/content/fig99_1.tif" xmlns:xlink="https://www.w3.org/1999/xlink"/>