Diisopropylethylamine → 3-(4-Benzyloxy-phenyl)-2-[4-methyl-2-(morpholine-4-sulfonylamino)-pentanoylamino]-propionic acid tert-butyl ester

Participants

Reaction Steps

A solution of the product from Example AI ([S-(R*,R*)]-2-(2-amino-4-methyl-pentanoylamino)-3-(4-benzyloxy-phenyl)-propionic acid tert-butyl ester) (397 mg, 0.90 mmol), morpholine-4-sulphonyl chloride (334 mg, 1.8 mmol, prepared by the method of von Geldem, et al., J. Med. Chem., 1996;39:968-981), N,N-diisopropylethyl-amine (246 mg, 1.9 mmol), and DMAP (25 mg) in benzene (5 mL) was heated under reflux for 3 hours, then concentrated in vacuo and the residue dissolved in ethyl acetate, and washed with saturated NaHCO3 solution, water and brine, dried over anhydrous sodium sulfate, and concentrated in vacuo. The amber oil thus obtained was purified via flash chromatography (silica gel, 35% EtOAc/Hexane) to give 346 mg (65%) of the title compound as a yellow foam, mp=54-57° C.

Provenance & Evidence