Studies on pyrazine derivatives. XLVII. Synthesis and antibacterial activity of novel pyrazine derivatives with amidoxime moiety.

The new pyrazine derivatives exhibiting an antibacterial activity have been synthesized. Initial amidoxime 1 was obtained in the reaction of pyrazinecarbonitrile with hydroxylamine. Upon treatment of amidoxime with methyl iodide O-methyl derivative 2 was formed. Both amidoximes were transformed into imidoyl chlorides 3, 4. Then the chloride atom in those derivatives was substituted with various secondary amines giving appropriate oximes 5-18 and O-methyl-oximes 19 and 20. The obtained compounds were tested in vitro for their tuberculostatic activity. The inhibiting concentration (MIC) values were within 25-100 microg/mL. Their activity towards 25 strains of anaerobic and 25 strains of aerobic bacteria was also studied. Three compounds exhibited activity against both types of bacteria.