Fig. 1: Design and synthesis of naphthoquinone derivatives.

a A schematic on the characteristics of naphthoquinone derivatives that confer antimicrobial activities. b Synthetic routes for the synthetic naphthoquinone derivatives including compounds 6a, 6b, 6c, 6d, and 6e. c Molecular structure of compound 6c determined from the single-crystal X-ray analysis. Red: oxygen atom; Gray: carbon atom; White: hydrogen atom.