Activity, antibacterial hydrazones

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). 

Other reductive aminations of tylosin-related macrolides have been reported, including the synthesis of dimeric moieties which retain antibacterial activity [92,93]. Other modifications of the aldehyde group include a variety of hydrazone derivatives, reduction products, and C-alkylated analogues [83, 94]. 

The hemiketal products (11) and (12) have been converted to the corresponding oximes, hydrazones, and substituted amines (40,41). Although many of these derivatives exhibit substantial antibacterial activity, they are generally less active than the parent tetracyclines. 

As already indicated, many acylated quinoxalinethiones have been synthesized as potential pesticides/ Quinoxaline-2-thiones have been tested for antitubercular activity and 3-hydrazinoquinoxaline-2-thione has been incorporated into an antileprosy ointment/ Hydrazones of 3-hydrazinoquinoxaline-2-thione have antibacterial activity/... 

Miscellaneous In Vitro Actives — With antibacterial activity accompanied by some in vivo tolerance or nonbacterial chemotherapy data were the following additional reports triazenoimidazole, hydrazones of N-amino (cyclic) hexamethyleneimine,further reports on antibacterial mes-ionic oxadiazoles,oxamylhydroxamic acids, ° 5-fluropyrlmidines, ° and a dinitropyrrole. ° ... 

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