First, the enzymatic generation of (typically chiral) starting materials or intermediates for total synthesis campaigns is an elegant method for the precise oxidative manipulation or deracemization of bulk material. Generally, this strategy aims to generate synthons which are either not easily available by purely chemical methods or are difficult to obtain in the desired optical purity. Here, enzymes facilitate synthesis by complementing the tools available through conventional organic chemistry. Although, from a conceptional standpoint, this approach follows in the footsteps of the early examples of enzymes in synthesis (which were largely limited to lipases), the scope of available enzymes has been broadened immensely, and so has the variety of available functionalizations and accessible synthons. At the forefront of these advancements, the Renata group has been leading the use of iron-dependent enzymes for the oxyfunctionalization of early intermediates. For instance, in their concise five-step synthesis of mitrekaurenone, 10 the use of a dioxygenase-reductase fusion enzyme enabled the precise introduction of a hydroxyl group on an otherwise scarcely functionalized terpene scaffold. In a similar fashion, the use of an engineered P450BM3 variant previously developed for steroid oxidation enabled the early hydroxylation of a sclareolide epimer en route to the meroterpenoid polysin, among other terpenoids. In both of these studies, the authors used readily available starting materials from the chiral pool and employed oxygenases for their further functionalization. In addition to these terpenes, the Renata group has pursued a modular chemoenzymatic synthesis of the tetrapeptide GE81112 B1, a bacterial translation inhibitor produced by Streptomyces sp. which is composed of four unnatural amino acids. In this synthesis, non-heme -ketoglutaratedependent hydroxylases gave access to hydroxylated amino acids, such as 3-hydroxy-L-pipecolic acid and 4-hydroxyl-L-citrulline which could be combined by peptide coupling after suitable protection. This strategy could also be leveraged to explore structure-activity relationships as the hydroxylated analogues of L-proline and L-norleucine could be obtained in an analogous fashion. By employing a dynamic kinetic resolution strategy with thermostable amino acid transferases, the same group recently also demonstrated the preparation of enantioenriched -methylated amino acids. This provided access to building blocks bearing vicinal stereocenters, which could, for instance, be elaborated by ester and amide formation to give jomthonic acid, a soil-derived natural product with antidiabetic and antiatherogenic activities. Starting from perhaps more exotic synthons, the groups of Huang and Chen recently used a Baeyer-Villiger monooxygenase to desymmetrize a dichlorinated ketone to give the corresponding chiral ester, setting the stage for a subsequent Prins reaction and olefination en route to a variety of prostaglandins, among them PGF2. Notably, in addition to the early use of a monooxygenase, the authors also employed a ketoreductase for the stereoselective hydrogenation of a late branching point intermediate. Finally, in their synthesis of viridicatin, the groups of Chang and colleagues used the ketoglutarate-dependent oxygenase AsqJ to install an epoxide on a diketodiazepine scaffold where ring-contraction could be triggered by Lewis acid catalysis. Further elaboration of the obtained brominated quinolinone under Heck conditions afforded a diversely substituted set of viridicatin analogues.