AbstractA series of 4‐alkylthiopyridine‐2‐carbothioamides have been prepared and evaluatedin vitrofor antimicrobial activity. Chemical structures have been demonstrated by IR and1H NMR data and by elemental analysis. The antimycobacterial activity of these compounds againstMycobacterium tuberculosis, Mycobacterium kansasii, Mycobacterium avium, andMycobacterium fortuitum, and the antifungal activity againstCandida albicans, Candida tropicalis, Candida krusei, Candida glabrata, Trichosporon beigelii, Trichophyton mentagrophytes, Aspergillus fumigatus, andAbsidia corymbiferawere determined by the MIC values. Compounds3exhibit good antimycobacterial activity compared to isoniazide. A moderate antifungal activity was observed againstT. mentagrophytes.Activity is influenced by hydrophobicity of the alkyl