In a manner similar to the method described in Examples 42c, 42d, rac-(2R,3R,4R,5S)-3-(4-bromo-thiophen-2-yl)-4-(4-chloro-2-fluoro-phenyl)-4-cyano-5-(2,2-dimethyl-propyl)-pyrrolidine-2-carboxylic acid trifluoroacetic acid prepared in Example 70c (0.2 g, 0.33 mmol) was reacted with 2-4S)-2,2-dimethyl-[1,3]dioxolan-4-yl)-ethylamine (0.14 g, 1 mmol), HATU (0.22 g, 0.58 mmol) and iPr2NEt (0.28 mL, 1.63 mmol) in CH2Cl2 at room temperature for 20 h, then reacted with aqueous HCl solution in tetrahydrofuran at room temperature for 2 h to give rac-(2R,3R,4R,5S)-3-(4-bromo-thiophen-2-yl)-4-(4-chloro-2-fluoro-phenyl)-4-cyano-5-(2,2-dimethyl-propyl)-pyrrolidine-2-carboxylic acid ((S)-3,4-dihydroxy-butyl)-amide as a white solid (0.15 g, 80%).
