Diisopropylethylamine → benzyl ((25)-4-((4-((tert-butoxycarbonyl)amino)-1-methyl-1H-pyrazol-3-yl)amino)-1-hydroxy-4-oxobutan-2-yl)carbamate

Beteiligte Stoffe

Reaktionsschritte

To a solution of tert-butyl (3-amino-1-methyl-1H-pyrazol-4-yl)carbamate (1.0 g), (3S)-3-(((benzyloxy)carbonyl)amino)-4-methoxy-4-oxobutanoic acid (1.5 g) and HATU (2.2 g) in DMF (24 mL) was added diisopropylethylamine (1.2 mL), and the mixture was stirred overnight at room temperature. The reaction mixture was poured into water, and the mixture was extracted with ethyl acetate. The extract was washed successively with saturated aqueous ammonium chloride solution, saturated aqueous sodium hydrogen carbonate solution and saturated brine, and dried over anhydrous magnesium sulfate, and the solvent was evaporated under reduced pressure to give a crude product (2.6 g). To a suspension of lithium borohydride (0.26 g) in THF (20 mL) was added a solution of the crude product (2.2 g) in methanol (10 mL) under ice-cooling, and the mixture was stirred at 0° C. for 1 hr. To the reaction mixture was added water, and the mixture was concentrated under reduced pressure. The residue was extracted with ethyl acetate, the extract was washed with saturated brine, and dried over anhydrous magnesium sulfate, and the solvent was evaporated under reduced pressure. The residue was purified by silica gel column chromatography (ethyl acetate/hexane) to give the title compound (1.6 g).

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