Impact of the β-turn hydrogen bond on the trans/cis ratio and the performance of the peptide catalyst H-dPro-Pro-Glu-NH2

Abstract

The effect of the β-turn hydrogen bond on the trans/cis conformer ratio and the catalytic performance of the peptidic catalyst H-dPro-Pro-Glu-NH2 was investigated. Different electron withdrawing and donating substituents at the C-terminus of peptide analogues caused changes in the trans/cis ratio and the enantioselectivities of the peptides in conjugate addition reactions of aldehydes to nitroolefins. The results imply that the β-turn H-bond contributes but is not critical for the catalytic performance of H-dPro-Pro-Glu-NH2 and related peptidic catalysts. © 2020 Elsevier