We report the development and optimization of a tetrapeptide that catalyzes the methanolytic dynamic kinetic resolution of oxazol-5 (4 H)-ones (azlactones) with high levels of enantioinduction. Oxazolones possessing benzylic-type substituents were found to perform better than others, providing methyl ester products in 88: 12 to 98: 2 er. The mechanism of this peptide-catalyzed process was investigated through truncation studies and ...