Acetone → (S)-2-Amino-3-methylbutyric Acid 3-Acetyl-5-[N'-((R)-2-carboxy-2-hydroxyethyl)-N'-(5'-chloro-2'-fluorobiphenyl-4-ylmethyl)hydrazinocarbonyl]pyrazol-1-ylmethyl Ester

Participants

Reaction Conditions

Reaction Steps

(R)-3-[N′-(5-Acetyl-2H-pyrazole-3-carbonyl)-N-(5′-chloro-2′-fluorobiphenyl-4-ylmethyl)hydrazino]-2-hydroxypropionic acid (95.5 mg, 0.2 mmol) was dissolved in acetone (886 μL, 12.1 mmol). Et3N (70 μL, 503 μmol) and (S)-2-t-butoxycarbonylamino-3-methyl-butyric acid chloromethyl ester (56.1 mg, 211 μmol) were added, and the resulting mixture was stirred at 60° C. for 6 hours. The solvent was removed in vacuo and the residue was purified using flashy chromatography (normal phase; MeOH:EtOAc=0:50). The pure fractions were collected, concentrated, then dissolved in MeCN (630 μL, 12.1 mmol). A solution of 4.0 M HCl in 1,4-dioxane (503 μL, 2.0 mmol) was added, and the resulting mixture was stirred at room temperature for 2 hours. The solvent was removed in vacuo to yield the title compound (90 mg).

Provenance & Evidence