Enantioselective β-carbonyl Alcohol Dehydration Reaction Mediated By A Dehydratese β-turn Peptide Mimic

In living systems, proteases have a superior chiral recognition ability, they have evolved to accelerate one of the racemic isomers to start biochemical reactions. Therefore, researches on kinetic resolution of important chiral compounds and the chiral phenomenon in living systems via protease have the great value. However, many characteristics of proteases, such as the complexity of structure, narrow substrates and instability in vitro, hinder their in-depth study. Synthetic biomimetic peptides with higher conformation structures, which can imitate the enzyme-mediated reactions well, have great theoretic values in the explanation of enzyme catalytic mechanism.The dehydratase-catalyzed dehydration reaction is one of the most fundamental biochemical reactions, but researches on selective dehydration of racemic substrates have no report by our knowledge. Here, we present a series of biomimeticβ-turn tetrapeptide catalysts for the kinetic resolution of racemicβ-carbonyl alcohol substrates. The reaction proceeds via an enantioselective dehydration protocol, which achieved chiral nonracemicβ-carbonyl alcohol compounds with excellent enantioselectivities, which is up to 97%ee. Furthermore, we can get two products in one reaction, one is chiralβ-carbonyl alcohol, the other isα,β-unsaturated carbonyl compound. Both of them often appear in natural products and are valuable as synthetic intermediates. More broadly, the approach described herein may also stimulate related research involving mimetic peptide of enzyme and dehydratase.