Nitroimidazoles are the group of

organic compounds Some chemical authorities define an organic compound as a chemical compound that contains a carbon–hydrogen or carbon–carbon bond; others consider an organic compound to be any chemical compound that contains carbon. For example, carbon-co ...

consisting of an

imidazole Imidazole (ImH) is an organic compound with the formula . It is a white or colourless solid that is soluble in water, producing a mildly alkaline solution. It can be classified as a heterocycle, specifically as a diazole. Many natural products, ...

ring with at least one

nitro group In organic chemistry, nitro compounds are organic compounds that contain one or more nitro functional groups (). The nitro group is one of the most common explosophores (functional group that makes a compound explosive) used globally. The nit ...

substituent. The term also refers to the class of antibiotics that have nitroimidazole in their structures. These antibiotics commonly include the 5-nitroimidazole

positional isomer In chemistry, a structural isomer (or constitutional isomer in the IUPAC nomenclature) of a compound is a compound that contains the same number and type of atoms, but with a different connectivity (i.e. arrangement of bonds) between them. The ...

Synthesis

Imidazole Imidazole (ImH) is an organic compound with the formula . It is a white or colourless solid that is soluble in water, producing a mildly alkaline solution. It can be classified as a heterocycle, specifically as a diazole. Many natural products, ...

undergoes a

nitration In organic chemistry, nitration is a general class of chemical processes for the introduction of a nitro group () into an organic compound. The term also is applied incorrectly to the different process of forming nitrate esters () between Alcohol ...

reaction with a mixture of

nitric acid Nitric acid is an inorganic compound with the formula . It is a highly corrosive mineral acid. The compound is colorless, but samples tend to acquire a yellow cast over time due to decomposition into nitrogen oxide, oxides of nitrogen. Most com ...

and

sulfuric acid Sulfuric acid (American spelling and the preferred IUPAC name) or sulphuric acid (English in the Commonwealth of Nations, Commonwealth spelling), known in antiquity as oil of vitriol, is a mineral acid composed of the elements sulfur, oxygen, ...

to give 5-nitroimidazole.

Nitroimidazole antibiotics

From the chemistry perspective, nitroimidazole antibiotics can be classified according to the location of the nitro

functional group In organic chemistry, a functional group is any substituent or moiety (chemistry), moiety in a molecule that causes the molecule's characteristic chemical reactions. The same functional group will undergo the same or similar chemical reactions r ...

. Structures with names 4- and 5-nitroimidazole are equivalent from the perspective of drugs since these tautomers readily interconvert. Drugs of the 5-nitro variety include

metronidazole Metronidazole, sold under the brand name Flagyl and Metrogyl among others, is an antibiotic and antiprotozoal medication. It is used either alone or with other antibiotics to treat pelvic inflammatory disease, endocarditis, and bacterial vagino ...

tinidazole Tinidazole, sold under the brand name Tindamax among others, is a medication used against protozoan infections. It is widely known throughout Europe and the developing world as a treatment for a variety of anaerobic amoebic and bacterial infecti ...

nimorazole Nimorazole (INN) is a nitroimidazole anti-infective. It is also being investigated for the treatment of head and neck cancer Head and neck cancer is a general term encompassing multiple cancers that can develop in the head and neck region. The ...

dimetridazole Dimetridazole is a drug that combats protozoan infections. It is a nitroimidazole class drug. It used to be commonly added to poultry feed. This led to it being found in eggs. Because of suspicions of it being carcinogenic its use has been legal ...

pretomanid Pretomanid is an antibiotic medication used for the treatment of multi-drug-resistant tuberculosis affecting the lungs. It is generally used together with bedaquiline and linezolid. It is taken by mouth. The most common side effects include ...

ornidazole Ornidazole is an antibiotic used to treat protozoan infections. A synthetic nitroimidazole, it is commercially obtained from an acid-catalyzed reaction between 2-methyl-5-nitroimidazole and epichlorohydrin. Ornidazole is nothing but chloro-secn ...

megazol Megazol (CL 64855) is a nitroimidazole based drug that cures some protozoan infections. A study of nitroimidazoles found the drug extremely effective against '' T. cruzi'' and '' T. brucei'' which cause Chagas disease and African sleeping sickn ...

, and

azanidazole Azanidazole is a nitroimidazole derivative used in gynecology Gynaecology or gynecology (see American and British English spelling differences) is the area of medicine concerned with conditions affecting the Female reproductive system, female ...

. Drugs based on 2-nitroimidazoles include

benznidazole Benznidazole is an antiparasitic medication used in the treatment of Chagas disease. While it is highly effective in early disease, the effectiveness decreases in those who have long-term infection. It is the first-line treatment given its mod ...

and azomycin. Nitroimidazole antibiotics have been used to combat

anaerobic Anaerobic means "living, active, occurring, or existing in the absence of free oxygen", as opposed to aerobic which means "living, active, or occurring only in the presence of oxygen." Anaerobic may also refer to: *Adhesive#Anaerobic, Anaerobic ad ...

bacterial Bacteria (; : bacterium) are ubiquitous, mostly free-living organisms often consisting of one biological cell. They constitute a large domain of prokaryotic microorganisms. Typically a few micrometres in length, bacteria were among the ...

and

parasitic Parasitism is a close relationship between species, where one organism, the parasite, lives (at least some of the time) on or inside another organism, the host, causing it some harm, and is adapted structurally to this way of life. The ent ...

infection An infection is the invasion of tissue (biology), tissues by pathogens, their multiplication, and the reaction of host (biology), host tissues to the infectious agent and the toxins they produce. An infectious disease, also known as a transmis ...

s. Perhaps the most common example is

. Other heterocycles such as nitrothiazoles (

thiazole Thiazole (), or 1,3-thiazole, is a 5-membered heterocyclic compound that contains both sulfur and nitrogen. The term 'thiazole' also refers to a large family of derivatives. Thiazole itself is a pale yellow liquid with a pyridine-like odor and the ...

) are also used for this purpose. Nitroheterocycles may be reductively activated in

hypoxic Hypoxia means a lower than normal level of oxygen, and may refer to: Reduced or insufficient oxygen * Hypoxia (environmental), abnormally low oxygen content of a specific environment ** Hypoxia in fish, responses of fish to hypoxia * Hypoxia (medi ...

cells, and then undergo

redox Redox ( , , reduction–oxidation or oxidation–reduction) is a type of chemical reaction in which the oxidation states of the reactants change. Oxidation is the loss of electrons or an increase in the oxidation state, while reduction is t ...

recycling or

decompose Decomposition is the process by which dead organic substances are broken down into simpler organic or inorganic matter such as carbon dioxide, water, simple sugars and mineral salts. The process is a part of the nutrient cycle and is essen ...

to toxic products.

References

{{Nucleic acid inhibitors Disulfiram-like drugs