Synthesis of New 2-N,N' ­ dialkylamino-1,4-naphthoquinone Derivatives: Concerning the Reactivity of Lapachol with Secondary Amines

The reactivity of 2-methoxy-naphthoquinones with secondary amines can be modified by the presence of side-chain substituents in natural and synthetic quinones. We report the synthesis of 2-dialkylamino-1,4-naphthoquinone derivatives by nucleophilic substitution with secondary amines using 2-methoxy-1,4-naphthoquinones derived from nor-lapachol and lawsone. The reported reactions show good yields and straightforward experimental conditions. No products were obtained for the reaction of 2-methoxy-lapachol with secondary amines under the studied experimental conditions. The compounds were characterized by H-1, C-13 NMR spectroscopy, HMBC, IR and by comparing with literature data.