Formula C3H3N3O2 Melting point 303 °C | Molar mass 113.07 g/mol | |
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Nitroimidazole
5-Nitroimidazole is an organic compound with the formula O2NC3H2N2H. The nitro group at position 5 on the imidazole ring is the most common positional isomer. The term nitroimidazole also refers to a class of antibiotics that share similar chemical structures.
Contents
2-Nitroimidazole (azomycin) is used in the synthesis of Etanidazole.
Synthesis
Imidazole reacts with a mixture of nitric acid to give 5-nitroimidazole:
C3H3N2H + HNO3 → O2NC3H2N2H + H2OUnder conventional conditions for nitration, the reaction is conducted in the presence of sulfuric acid.
Nitroimidazole antibiotics
From the chemistry perspective, nitroimidazole antibiotics can be classified according to the location of the nitro functional group. 4- and 5-nitroimidazole are equivalent from the perspective of drugs since these tautomers readily interconvert. Drugs of the 5-nitro variety include metronidazole, tinidazole, nimorazole, dimetridazole, 6-Amino PA824, ornidazole, megazol, and azanidazole. Drugs based on 2-nitromidazoles include benznidazole.
Nitroimidazole antibiotics have been used to combat anaerobic bacterial and parasitic infections. Perhaps the most common example is metronidazole. Other heterocycles such as nitrothiazoles (thiazole) are also used for this purpose. Nitroheterocycles may be reductively activated in hypoxic cells, and then undergo redox recycling or decompose to toxic products.
Related groups
If a pyran ring is attached it produces a nitroimidazopyran, eg. as in the drug pretomanid