The series of 2-benzylsulfanyl derivatives of benzoxazole and benzothiazole were synthesized, evaluated for their in vitro antimycobacterial activity against Mycobacterium tuberculosis and non-tuberculous mycobacteria, and the activity expressed as the minimum inhibitory concentration (MIC) in micromol/L. The substances bearing two nitro groups (4e, 4f, 5e, 5f) or a thioamide group (4i, 4j, 5i, 5j)
exhibited significant activity against both sensitive and resistant strains of M. tuberculosis and also against non-tuberculous mycobacteria. To facilitate drug design of benzoxazole as potentialantituberculosisagent, we have explored the quantitative structure–activity relationship (QSAR). We demonstrated that lower lipophilicity has significant contribution to activity. Dinitrobenzylsulfanyl derivative