Diisopropylethylamine → (S)-methyl 3-(3-(benzyloxy)-4-methoxyphenyl)-2-((S)-2-((tert-butoxycarbonyl)amino)-3-hydroxypropanamido)propanoate

Beteiligte Stoffe

Reaktionsschritte

Crude (S)-methyl 2-amino-3-(3-(benzyloxy)-4-methoxyphenyl)propanoate (TFA salt, 12 mmol) was dissolved in DMF (50 mL) followed by addition of Boc-L-serine (2.47 g, 12 mmol), HATU (6.87 g, 18.1 mmol) and DIPEA (10 mL) at 0° C. with stirring. The reaction mixture was allowed to warm to ambient temperature and stirred for 3 h. EtOAc (200 mL) and water (200 mL) was added and two layers were separated. The aqueous phase was extracted with EtOAc (100 mL×3) and the combined organic phases were washed with brine (200 mL×3), dried over anhydrous sodium sulfate, and concentrated. The residue was purified by flash column chromatography on silica gel (CH2Cl2/methanol (MeOH)=20:1) to afford (S)-methyl 3-(3-(benzyloxy)-4-methoxyphenyl)-2-((S)-2-((tert-butoxycarbonyl)amino)-3-hydroxypropanamido)propanoate (4.4 g, 73% yield).

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