Diisopropylethylamine → HCID 68725930, compound

Participants

Reaction Steps

(S)-3-(4-benzyloxy-3-hydroxy-phenyl)-2-tert-butoxycarbonylamino-propionic acid (465 mg) was dissolved in anhydrous DMA (5 ml) and HBTU (910 mg) added in portions followed by methyl 2-aminoisobutyrate hydrochloride (366 mg). N,N-Diisopropylethylamine (0.4 ml) was added and the solution stirred at room temperature for 3 days. The mixture was diluted with water and ethyl acetate. The aqueous phase was extracted with ethyl acetate and the combined organic extracts were washed with dil HCl, with aq sodium bicarbonate with water and with brine. Drying (MgSO4) and evaporation of solvent gave the crude 2-[(S)-3-(4-benzyloxy-3-hydroxy-phenyl)-2-tert-butoxycarbonylamino-propionylamino]-2-methyl-propionic acid methyl ester as a gum, 690 mg; HPLC/MS retention time 5.77 min, m/z 487.

Provenance & Evidence