Engineering Ene-Reductases for the Chemoenzymatic Synthesis of a Sacubitril Intermediate and Its Derivatives

The availability of an effective ene-reductase (ER) for the synthesis of Sacubitril intermediates represents a major challenge. Herein, we report the engineering of ClER and GoER utilizing three different substrates to synthesize the key Sacubitril precursor. The best performing variant, ClER M3 (M35C/Y76C/Q244G/V289P), enables substrate loadings of up to 100 mM with up to 99% yields and ee. This chemoenzymatic strategy provides a valuable platform for the reduction of challenging α,β-unsaturated carboxylic acids bearing large substituents, such as biphenyls or naphthyl motifs.