Facile Synthesis of Azaarene-Substituted Hydroxycoumarins Possessing High Biological Activities via Three-Component C(sp3)–H Functionalization

An unprecedented three-component C­(sp3)–H functionalization of 2-alkylazaarenes with aryl aldehydes and 4-hydroxycoumarins was realized, providing azaarene-substituted 3-benzyl-4-hydroxycoumarins in good to excellent yields. These new target compounds displayed broad-spectrum antibacterial activities, providing a new type of antibacterial skeleton.