Geodin (CAS: 427-63-4)

(+)-Geodin is a chlorinated polyketide secondary metabolite produced by Aspergillus terreus and related Aspergillus species. It is formed through a regio- and stereospecific oxidative phenol-coupling reaction catalyzed by the blue copper enzyme dihydrogeodin oxidase during biosynthesis. Geodin and its semi-synthetic derivatives exhibit significant antibacterial activity against Staphylococcus aureus and Aeromonas salmonicida, potent antifungal activity against Candida albicans, and measurable insecticidal effects. Structure-activity relationship studies indicate that substitution at the 4-OH position enhances antimicrobial potency. Geodin serves as both a biosynthetic model for copper-dependent oxidative coupling and a scaffold for antimicrobial and agrochemical development.