Bio-Based Approaches for Selective Cyclization

Cyclic natural products offer important, unique scaffolds and functionalities for the pharmaceutical industry. They are produced by enzymes catalyzing a wide range of cyclization reactions. This large family of enzymes creates distinctive cyclic structures via a variety of mechanisms naturally evolved for selectivity. In this review, we aim to present an overview of these natural catalysts, the therapeutic compounds for which they are involved in the production, as well as engineering efforts to tune them for anthropogenic needs in human medicine. Biochemical methodologies commonly used for the discovery and engineering of enzymes will also be highlighted, with an emphasis on enzymatic terpene cyclization and Pictet-Spengler-type cyclization.