A new series of 23 6, 7-difluoro-3-methyl-2-phenylthio/phenylsulfonyl/phenylsulfinyl/ benzylamino/phenylamino-quinoxaline 1, 4-dioxides variously substituted in the phenyl moiety, was synthesized and submitted to in vitro evaluation for anti-mycobacterial, anti- trichomonas, anti-candida, anti-mycoplasma and antibacterial activities. In anti- mycobacterial assays, several compounds resulted active (MIC90= 2.0–4.0 μg/ml) against ...