Diisopropylethylamine → (S)[1-{(2-tert-Butoxycarbonylamino-ethyl)-[(2-methyl-2-phenyl-propylcarbamoyl)-methyl]-carbamoyl}-2-(1-trityl-1H-imidazol-4-yl)-ethyl]-carbamic acid benzyl ester

Participants

Reaction Steps

The compound from Step 3 (1.3 g, 1.8 mmol) was dissolved in methylene chloride (10 mL). β,β-dimethylphenethylamine hydrochloride (Example 1, Step 6) (0.370 g, 2 mmol) was added followed by diisopropylethylamine (1 mL, 5.7 mmol) and PyBOP (1.04 g, 2 mmol) dissolved in methylene chloride (10 mL). The reaction was stirred overnight at room temperature. The solution was concentrated, the residue taken up in ethyl acetate and washed three times with saturated NaHCO3, brine, dried over MgSO4, filtered and concentrated to give a white solid; 1.09 g (70% yield). MS-APCI: M+1=863.

Provenance & Evidence