Halofantrine is a drug used to treat malaria. Halofantrine's structure contains a substituted phenanthrene, and is related to the antimalarial drugs quinine and lumefantrine. Marketed as Halfan, halofantrine is never used to prevent malaria and its mode of action is unknown.
Trovafloxacin (sold as Trovan by Pfizer and Turvel by Laboratorios Almirall) is a broad spectrum antibiotic that inhibits the uncoiling of supercoiled DNA in various bacteria by blocking the activity of DNA gyrase and topoisomerase IV.[1] It was withdrawn from the market due to the risk of hepatotoxicity.