Abstract
Introduction: Menaquinone is used for transporting electrons and is essential for the aerobic and anaerobic respiratory systems of all pathogens and prokaryotes. Many Gram-positive bacteria use only menaquinone in the electron transport system. Thus, menaquinone biosynthesis is a potential target for the development of inhibitors against bacteria including drug-resistant pathogens. Results: After modeling, synthesis and in vitro testing, we determined that 7-methoxy-2-naphthol-based inhibitors targeted the MenA enzyme of the menaquinone biosynthesis pathway. The developmental compounds 1 and 2 were active against Mycobacterium tuberculosis and methicillin-resistant Staphylococcus aureus with a minimal inhibitory concentration of 3–5 μg/ml. Conclusion: Nontraditional bicyclic inhibitors, compounds 1 and 2 could serve as lead compounds for the development of an antimicrobial agent, with activities against M. tuberculosis and methicillin-resistant S. aureus.
Papers of special note have been highlighted as: • of interest; •• of considerable interest
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