Recent advances in nitroaromatics: The synthesis and development of anti-infective drugs.

Infectious diseases commonly occur in tropical and sub-tropical countries. The pathogens of such diseases are able to multiply in human hosts, warranting their continual survival. Infections that are commonplace include malaria, chagas, trypanosomiasis, giardiasis, amoebiasis, toxoplasmosis and leishmaniasis. Malaria is known to cause symptoms, such as high fever, chills, nausea and vomiting, whereas the chagas disease causes enlarged lymph glands, muscle pain, swelling and chest pain. People suffering from African trypanosomiasis may experience severe headaches, irritability, extreme fatigue and swollen lymph nodes. As an infectious disease progresses, the human host may also experience personality changes and neurologic problems. If left untreated, most of these diseases can lead to death. Parasites, microbes and bacteria are increasingly adapting and generating strains that are resistant to current clinical drugs. Drug resistance creates an urgency for the development of new drugs to treat these infections. Nitro containing drugs, such as chloroamphenicol, metronidazole, tinidazole and secnidazole had been banned for use as antiparasitic agents, due to their toxicity. However, recent discoveries of nitro containing anti-tuberculosis drugs, i.e. delamanid and pretonamid, and the re-purposing of flexinidazole for use in combination with eflornithine for the treatment of human trypanosomiasis, have ignited interest in nitroaromatic scaffolds as viable sources of potential anti-infective agents. This review highlights the differences between old and new nitration methodologies. It furthermore offers insights into recent advances in the development of nitroaromatics as anti-infective drugs.