4-Methylmorpholine → (4-N-tert-butoxycarbonylpiperazinylmethyl-2-phenylbenzoyl)methionine methyl ester

Participants

Reaction Steps

A solution of the product of Example 290A (0.544 g, 1.37 mmol), L-methionine, methyl ester hydrochloride (0.553 g, 2.74 mmol), 3-hydroxy-1,2,3-benzotriazin-4(3H)-one (1.14 g, 6.85 mmol), 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide (1.34 g, 6.85 mmol), and N-methylmorpholine (0.980 g, 9.59 mmol) in DMF (14 nlL) was stirred at ambient temperature for 16 hours. The mixture was diluted with ethyl acetate and then extracted with a 2:1 mixture of H2O and saturated aqueous NaHCO3 (2×), a 1:1 mixture of the same (2×) and brine (2×). The organic phase was dried (MgSO4) and concentrated to provide an amber oil. Radial chromatography (1:1 hexane-ethyl acetate) afforded the desired compound (0.356 g, 48%) as an amber oil.

Provenance & Evidence