Biosynthesis of Depsides, Depsidones, and Diphenyl Ethers from Fungi and Lichens

Depsides are a class of natural products in which two or more (poly)phenolic acid derivatives are linked by an ester bond. Depsides and related natural products, such as depsidones and diphenyl ethers, are widespread in nature and exhibit a wide range of biological activities. Although their biosynthesis has attracted considerable research interest for many decades, it remained largely elusive until recently. Recent studies have revealed the molecular mechanisms underlying the biosynthesis of several depsides and related natural products, uncovering unique enzymatic chemistry in their biosynthetic pathways. This review summarizes the biosynthetic pathways and mechanisms for depsides, depsidones, and diphenyl ethers, focusing on fungi and lichens, which are the primary producers of these compounds.