1-Hydroxybenzotriazole → {[(S)-2-tert-Butoxycarbonylamino-3-(2-nitro-benzenesulfonylamino)-propionyl]-methyl-amino}-acetic acid ethyl ester

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

To a solution of compound A (10.0 g, 25.7 mmol) in DMF (100 mL) was added HOBt (5.2 g, 38.5 mmol) and the reaction mixture was cooled to −10° C. To this reaction mixture, EDC-HCl (5.4 g, 28.2 mmol) was added in portions over 10 min and stirred at −10° C. for 20 min. To the reaction mixture, Sarcosine ethyl ester (256.8 mmol) in CHCl3 (300 mL) was added drop wise over 30 min. The reaction mixture was stirred at this temperature for 30 min followed by stirring at ambient temperature overnight. Solvents were then removed in vacuo, and the residue was dissolved in EtOAc (500 mL), washed with water (3×300 mL), saturated aqueous NaHCO3 (2×300 mL) and brine (100 mL). The organic layer was separated, dried over Na2SO4 and concentrated in vacuo to afford compound B (11.5 g, 91%) as a cream solid. LC-MS [M+H] 489.5 (C19H28N4O9S+H, calc: 489.3). Purity >95% (UV/254 nm). Compound B was used without further purification.

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