Secondly, the elaboration of late-stage intermediates to the final product (commonly also termed an endgame) with an enzyme is a relatively new area of research, which profits from the ability of enzymes to discriminate between multiple reactive moieties and facilitate precise transformations on highly functionalized compounds. In contrast to the examples above, a surprisingly diverse array of enzyme functions has recently found applications in endgame transformations. While the Sherman group used a promiscuous P450 monooxygenase to diversify the scaffold of tirandamycin via repeated hydroxylation, several groups employed P450 enzymes for biaryl coupling reactions. For instance, the Gulder group furnished the bityrosine motif of arylomycin by enzymatic coupling following construction of the peptide backbone by solid phase synthesis. The groups of Seyedsayamdost and Tailhades and Cryle independently used OxyB, a P450 from vancomycin biosynthesis, to introduce a variety of different aryl connections into linear peptides with (sometimes only distant) structural similarity to the native substrate. Complementing the previously mentioned work with the oxygenase AsqJ, the Gulder group employed this enzyme for ring contractions yielding quinazolinones through a radical mechanism relying on the absence of stabilizing effects in non-native substrates. Aside from irondependent enzymes, flavoenzymes, prenyltransferases and SAM-dependent enzymes have recently enjoyed increased attention. For instance, the Renata group used a flavindependent halogenase for the regioselective installation of a chloride substituent in their total synthesis of fasamycin. The groups of Rudolf and Elshahawi independently employed promiscuous prenyltransferases for the late-stage diversification of arenes and arene-bearing peptides. By employing the methyltransferase PsmD for concurrent C-Hmethylation and stereoselective cyclization, the Pietruszka group gained access to physostigmine and analogues thereof featuring different acylation profiles. Finally, the groups of Tang, Houk and Garg used the strictosidine synthase from Catharanthus roseus for the final stereoselective Pictet-Spengler reaction to furnish strictosidine.