Design of Peptidyl Thiourea Derivatives as Organocatalysts for the Asymmetric Ring Opening of meso-Stilbene Oxides

Chiral peptidyl thiourea organocatalysts were designed and synthesized for asymmetric ring-opening of cis-stilbene oxides with N-phenylpiperazines. Chiral beta-amino alcohols were obtained with up to 95% ee after crystallization. The configuration at the N-terminal residue stereogenic center of peptidyl thiourea organocatalyst was found to affect the stereochemical outcome of the reaction.