Two-step, high-yielding total synthesis of antibiotic pyrones.

A simple two-step dialkylation protocol was developed to synthesize biologically active antibiotics photopyrones, pseudopyronines, and violapyrones from bio-renewable triacetate lactone in excellent yields. These pyrones are functionally modified into another set of pyrone natural products by a single O-methylation reaction. The high-yielding gram scale synthesis of four natural products [pseudopyronine A, photopyrone A, pseudopyronine B and photopyrone C] demonstrated the viability for industrial applications.