Nitrofuran chemical structures

For example, the original scarlet red colour changes to yellow on heating for 30 minutes at 120° and the chemical structure of the compound changes considerably (see p. 338). The bacteriostatic activity of the yellow solution against dysentery bacillus is about 250 times greater than that of panazone. This observation has prompted the synthesis of other di-(nitrofuran) derivatives, some of which are listed in Table 6.8. 

Fig. 1 Chemical structures of nitrofuran parent drug compounds, the metabolites, and their 2-NBA nitrophenyl derivatives.

The synthesis, antimicrobial activity, and biodeterioration resistance of cellulose 5-nitrofuran derivatives and furan derivatives of model saccharides have been studied, and the relationship between their biological properties and chemical structures was discussed. ... 

The nitroimidazoles are antiprotozoal drugs, with antimicrobial activity. The main nitroimidazole used in human medicine is metronidazole, whereas in veterinary medicine it is dimetridazole. Ronidazole and ipronidazole have also been used. The chemical structure of these drugs is similar to that of the nitrofurans except the nitrofuran heterocyclic ring is replaced with that of the nitroimidazole ring. The chemical structures of the nitroimidazoles are shown in Figure 12.17. 

A number of studies in this area have been prompted by interest in the antibacterial activity of hydrazone derivatives of 5-nitrofurfuraldehyde having the general structure 33 (R1 = CH = N-NR2, R3 = R4 = H). The antibacterial activity, and associated carcinogenic and mutagenic activities, of these 2-nitrofurans are related to reduction of the nitro group, which has led to chemical studies of the reductive process (Table 5). Early work on the reduction of 2-nitrofurans has previously been reviewed (74H391). 

The electrochemical method was also [86] used to obtain radical anions from 2-nitrofuran and eight of its derivatives containing substituents in the 3-, 4-, and 5-positions the EPR spectra of these compounds had well-resolved hyperfine structure and contained nearly all the theoretically derived constants. These radicals were obtained in aqueous and in aqueous ethanolic solutions, and a method was developed for stud3dng the kinetics of their disappearance [76, 77]. It was shown that the hyperfine coupling constants in the spectra for these radicals correlated linearly with data from quantum-chemical calculations. 

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