The Synthesis of Chiral γ‐Lactones by Merging Decatungstate Photocatalysis with Biocatalysis

Abstract

Supporting information for this article is given via a link at the end of the document.

Exciting Enzymes: Current State and Future Perspective of Photobiocatalysis

“…[16] EPC-systems often combine photocatalytic bond-forming steps to provide a scaffold for a follow-up biocatalytic reaction (Figure 1d). [19] Hyster and co-workers developed strategies via photoexcitation for forming carbon-centered radicals from organohalides and acetates, using flavin-dependent EREDs (Figure 2a), [61] demonstrating the ability of this enzyme family to control the stereochemical outcome of radical reactions. [62] This approach has been further expanded to an ERED-based photoenzymatic platform capable of harnessing nitrogencentered radicals for CÀ N bond formation (Figure 2b).…”

“…[16] This can be done either via the direct incorporation of photocatalysts in a protein scaffold (Figure 1c), [16,18,[55][56][57][58] or in so-called photochemo-enzymatic cascade reactions (EPCsystems; Figure 1d). [1,19,23,[59][60] As an example of the former case, recently, a triplet state energy transfer PE that performs [2 + 2] cycloadditions was constructed by incorporation of a photoactive non-canonical amino acid into a protein scaffold, [18] a development that raises the opportunity to transfer the vast reaction scope of triplet sensitization chemistry to biocatalysis. In this context, also the conjugation of photocatalysts to protein scaffolds via covalent bonds was successfully applied.…”

“… The three disciplines of photobiocatalysis: PE: photoenzymes, including ( a ) natural photoenzymes (e. g., FAP) [9] as well as ( b ) photo‐promiscuous enzymes (e. g., ERED catalyzed C−C bond formation) [17] and ( c ) enzymes that are linked to a photosensitizer (e. g., [2+2] cycloaddition by an enzyme with a non‐canonical amino acid), [18] all requiring light in their mechanism. EPC: enzyme‐photosensitizer coupled systems, that either ( d ) combine photocatalytic reactions with an enzyme in a synthetic cascade (e. g., photocatalytic C−C bond formation and biocatalytic keto‐reduction), [19] or ( e ) use external photosensitizers to provide redox equivalents for a biocatalyst (e. g., regeneration of FMNH 2 for EREDs) [20] . NPC: natural photosynthesis coupled systems, that utilize living photoautotrophic cells, either ( f ) to supply redox enzymes with cofactors, electrons or oxygen, based on photosynthetic water splitting (e. g., reduction of C=C bonds using EREDs), [21] or ( g ) for their ability to produce chemicals from CO 2 and light (e. g., production of 1‐butanol from CO 2 ) [22] .…”

Evaluating Multienzyme Cascade Routes for Pharmaceutically Relevant Molecules

“…This approach has turned out to be extremely widespread and currently, many groups worldwide are focusing on developing enzyme cascade synthesis to find new innovative synthetic routes to various important chiral building blocks and bioactive molecules. [8][9][10][11][12] Living cells can be considered as "synthetic factories" given that multiple enzymes work in a relay to catalyze the biosynthesis of various molecules with the highest order of complexity without interfering with, or hampering each other's reactivity. Using this approach, scientists have come up with the idea of combining multiple enzymes in a single pot to catalyze a relay of transformations.…”

“…Additionally, conducting multiple steps in an enzymatic cascade saves time, and resources thus leading to a prompt and cost‐efficient process. This approach has turned out to be extremely widespread and currently, many groups worldwide are focusing on developing enzyme cascade synthesis to find new innovative synthetic routes to various important chiral building blocks and bioactive molecules [8–12] …”