Compound 9b

(S)-3-((tert-Butoxycarbonyl)amino)-4-((S)-2-(((S)-1-(((R)-1-((S)-2-(((S)-1-methoxy-1,4-dioxo-4-(tritylamino)butan-2-yl)carbamoyl)pyrrolidin-1-yl)-1-oxo-3-phenylpropan-2-yl)amino)-1,4-dioxo-4-(tritylamino)butan-2-yl)carbamoyl)pyrrolidin-1-yl)-4-oxobutanoic acid

From: Combinatorial evolution of site- and enantioselective catalysts for polyene epoxidation