Synthesis and First-Time Assessment of o-Eugenol Derivatives against Mycobacterium tuberculosis

In this work, we report the first-time assessment of o-eugenol, 6-allyl-2-methoxyphenol, and their selected derivatives, against Mycobacterium tuberculosis H37RV, using the MABA susceptibility test. The bromo, nitro, O-alkylated, and reduced derivatives were obtained by standard methods and were characterized by spectroscopic and mass spectral data. Structure–activity relationships were investigated, with the most active derivatives being 4,5-dibromo-2-methoxy-6-propylphenol (139 μM) and 2-methoxy-3-nitro-6-propylphenol (237 μM). This study provides important information on the rational design of new lead anti-TB drugs based on o-eugenol derivatives.