Enzyme catalysed hydrolyses of dialkylated propanedioic acid diesters have been studied. A novel change of enantioselectivity from pro-S to pro-R in the hydrolysis of ester groups was observed, depending on the chain length of the alkyl substituents of the substrate. Optically pure (S)-(-)-α-methylphenylalanine was prepared by α-chymotrypsin catalysedhydrolysis of benzylmethylpropanedioic acid dimethyl
synthesis features a Catellani reaction/oxa‐Michael cascade for the construction of the isochroman scaffold, a one‐pot deprotection/spiroacetalization operation for the formation of the tetracyclic core structure, and a late‐stage Ni‐catalyzed reductive coupling for the introduction of the lateral chain. Notably, four stereocenters are established from a single existing chiral center with excellent stereocontrol