(2S,4R)-5-Biphenyl-4-yl-2-methyl-2-(tetrahydropyran-2-yloxymethyl)-4-[(1H-1,2,3-triazole-4-carbonyl)amino]pentanoic acid (126 mg, 255 μmol) was combined with 4 M HCl in dioxane (191 mL, 765 μmol) in MeCN (0.7 mL, 10 mmol). The mixture was then concentrated under reduced pressure and the residue was purified by reverse phase chromatography. DCM (1 mL, 20 mmol) and acetyl chloride (24 mg, 306 μmol) were added, followed by DIPEA (133 mL, 765 μmol). The resulting mixture was stirred for 10 minutes. The solvent was evaporated and the residue was dissolved in AcOH and purified by preparative HPLC to yield the title compound (5 mg). MS m/z [M+H]+ calc'd for C24H26N4O5, 451.19. found 451.
