Metabolism of the nitrofurans; ultraviolet absorption studies on urinary end-products after oral administration.

The general antibacterial action in vitro of a variety of furan derivatives substituted in the 5 position with a nitro group has been reported by Dodd and Stilhnan (1, 2). That the presence of the nitro group is essential was established by comparison of the activities with those of the corresponding non-nitrated derivatives. All the nitrofurans except those limited by insolubility exhibited a marked antibacterial action with the exception of nitrofuroic acid. The latter compound, in contrast, was but weakly active. With the in vitro activity of these derivatives firmly established, attention was directed to their possible use in the treatment of systemic infections. A report by Dodd (3) gave in detail the treatment of animal infections with one of the compounds, 5-nitro-2-furaldehyde semicarbazone (Furacin).’ In marked contrast to their behavior in vitro, not all of the nitrofurans gave a chemotherapeutic response in animal infections. An evaluation of more than sixty compound& 8 has shown that the presence of a semicarbazone or closely allied grouping as substituent in position 2 of the furan ring is almost uniquely favorable to pronounced response in this respect.