Peptide-Catalyzed Conversion of Racemic Oxazol-5(4H)-ones into Enantiomerically Enriched α-Amino Acid Derivatives
摘要:
We report the development and optimization of a tetrapeptide that catalyzes the methanolytic dynamic kinetic resolution of oxazol-5(4H)-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 competition experiments. High-field NOESY analysis was performed to elucidate the solution-phase structure of the peptide, and we present a plausible model for catalysis.
This paper reports the totalsynthesis of antibacterial cyclic hexapeptides nicrophorusamides A () and B (), isolated from the actinomycete strain UTG9 belonging to the genus . The synthesis involved solid-phase peptide elongation and solution-phase macrolactamization, followed by the removal of the protecting groups. Synthetic and demonstrated inhibitory effects on the growth of with minimum inhibitory