Empowering molecular complexity via biocatalysis: emerging blueprints in the total synthesis of medicinally relevant natural products

Biocatalysis has ascended as a defining force in contemporary total synthesis, furnishing catalytic modalities that deliver molecular complexity with unparalleled chemo-, regio-, and stereo-control. As structurally sophisticated therapeutics-including macrocyclic lactones, polyketides, terpenoids, alkaloids, and pharmacologically privileged scaffolds-continue to drive innovation, enzyme-mediated strategies provide mechanistically exquisite, environmentally consonant solutions that increasingly transcend the capabilities of traditional chemical catalysis. This review articulates the unifying principles and activation paradigms through which oxidoreductases, hydrolases, and transferases orchestrate the streamlined construction of architecturally dense natural products. In particular, emphasis is placed on cascade logic, mechanistically integrated chemoenzymatic platforms, and advances in enzyme engineering, which collectively furnish transformative blueprints for accessing next-generation bioactive architectures. By foregrounding conceptual frameworks rather than enumerating examples, this review positions biocatalysis as a central strategic axis at the intersection of synthetic methodology, chemical biology, and therapeutic discovery and as a driving force in shaping the future landscape of complex molecule synthesis (covering 2000-2025).