[Chemotherapeutically effective nitro compounds. 3rd communication: nitropyridines, nitroimidazopyridines and related...

New 2-nitropyridines and 3-nitropyridines, and 3-nitroimidazo-[1,2-a]-pyridines and related compounds (together 106) were synthesized and tested for their chemotherapeutic efficacy against trichomonads, amoebas and other organisms, such as Eimeria tenella, bacteria, fungi, helminths. Several 2-nitropyridines revelaed a detectable systemic effect against Entamoeba histolytica (extraintestinal amoebiasis of the golden hamster) and also a weak activity against Trichomonas fetus in the NMRI-mouse. Only a few 3-nitropyridines showed a marked systemic effect against trichomonads. Of the 3-nitroimidazo-[1,2-a]-pyridines, only the electroneutral carboxylic acid amide group exhibited a pronounced activity, exclusively against trichomonads; however, the activity was nullified again by electronegative, electropositive and other electroneutral substituents. As they were not superior in chemotherapeutic respect compared to the known standard preparation (metronidazole), no further tests were carried out with the most effective compounds.