Synthesis and Biological Evaluation of Naphthoquinone-Fused Pyrrole and Imidazopyridinedione Heterocycles

Abstract

We have developed an efficient and easy synthetic route to obtain naphthoquinone fused pyrrole derivatives (up to 93% yield) via intramolecular cyclization of 2-(arylethynyl)naphthalene-1,4-dione derivatives with NH4OAc in methanol at ambient temperature. Furthermore, imidazopyridinedione derivatives were synthesized via the coupling between 2-bromonaphthalene-1,4-dione and 2-amino pyridine through condensation and rearrangement under neat conditions in the presence of a catalytic amount of AcOH. A series of functionalized pyrrolonaphthoquinone and imidazopyridinedione derivatives are synthesized in high yields. Additionally, one of the synthesized pyrrolonaphthoquinones was chosen as a model substrate for analyzing cytotoxicity and antimicrobial activity against gram-positive and gram-negative biofilm bacteria.