Acetic Anhydride → 3,5-Dioxohexanoic acid

Participants

Reaction Steps

4-(4-(2-methyl-5-((2S,3R,4R,5S,6R)-3,4,5-trihydroxy-6-(methylthio)tetrahydro-2H-pyran-2-yl)benzyl)phenoxy)butanoic acid (39, 1.47 g, 3.2 mmol), 2-amino-2-methyl-1-(4-methylpiperazin-1-yl)propan-1-one (1.07 g, 2 HCl salt, 4.1 mmol), HATU (1.45 g, 3.8 mmol), and DIPEA (2.2 mL, 13 mmol) were combined in CH3CN (32 mL) and stirred overnight at room temperature. To the reaction were added DMAP (39 mg, 0.32 mmol), DIPEA (3.3 mL, 19 mmol), and acetic anhydride (1.5 mL, 16 mmol). The reaction was stirred for 1 hour, then quenched with saturated aqueous NaHCO3, stirred for 1 hour, and extracted twice with EtOAc. The combined organic phases were washed with brine, dried over MgSO4, filtered, and concentrated under vacuum. The residue was purified by silica gel chromatography (gradient 2-10% MeOH/CH2Cl2) to yield 2.27 g (94% yield) of triacetate as a yellow foam.

Provenance & Evidence