Nitrofurazone metabolism

The first drugs in this class to be introduced into clinical practice are simple derivatives of 5-nitrofurfural (18). Thus, the oxime is known as nitrofuroxime (19) while the semicarbazone is called nitrofurazone (20). In order to maintain better control over the distribution and metabolism of these antibacterial agents, increasingly complex side chains and rings have been grafted onto the hydrazone. 

Nitro groups in the furan ring are reduced easily by various biochemical processes . Nitrofurazone can function as an electron acceptor in a number of bacterial dehydrogenase systems involved in carbohydrate metabolism. 

In rats, the oxidative and reductive metabolism products have been identified as the 4-hydrox5iated fiiran and [(3-cyano-l-oxoprop5i)meth5ieneamino]-2-4-imidazolidinedione, respectively (27,42). In addition, the ease of electron transfer as a mechanism of activity with nitrofurantoin and nitrofurazone has been studied (43). 

The aromatic furan ring system, though not found in animal metabolism, occurs widely in secondary plant metabolites, especially in terpenoids perillene is a simple example. Vitamin C, ascorbic acid, is at the oxidation level of a trihydroxyfuran, though it assumes an unsaturated lactone tautomeric form. Though one normally associates thiols with unpleasant odours, furfuryl thiol is present in the aroma of roasted coffee. Some 5-nitrofurfural derivatives are important in medicine, Nitrofurazone, a bactericide, is a simple example. Ranitidine is one of the most commercially successful medicines ever developed it is used for the treatment of stomach ulcers. 

Under certain circumstances, respective parent antibiotics cannot be targeted as marker residues, and therefore, derivatization and chemical conversion are required. Nitrofurans including furazolidone, furaltadone, nitrofurazone, and nitrofurantoin are metabolized rapidly to 3-amino-2-oxazolidinone (AOZ),... 

Pereira AS, Donato JA, De Nucci G, Implications of the use of semicarbazide as a metabolic target of nitrofurazone contamination in coated products. Food Addit. Contam. 2004 21(l) 63-69. 

All reports should generally be checked independently by (ideally) two suitably qualified staff members. The laboratory should implement a policy regarding the provision of opinions and interpretation of data. The basis on which an opinion has been stated must be documented. An opinion or interpretation may include, but not be limited to, recommendations on how to use results, or information related to the pharmacology, metabolism, and pharmacokinetics of a substance. This is particularly important for classes of compounds for which the client/authority may not be aware of the latest developments or recent knowledge in the field, as is often the case, for instance, for natural hormones such as boldenone and nandrolone in breeding animals, compounds newly discovered to be naturally occurring such as thiouracil, and marker residues that may be unreliable such as semicarbazide as a marker for nitrofurazone abuse. °... 

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