4-Methylmorpholine → 3-Tert-butoxycarbonyl-5(S)-{2-[N-(1-carbamoyl-1-methyl-ethyl)-carbamoyl]-2(S)-isopropyl-ethyl}-4(S)-{2(S)-isopropyl-3-[4-methoxy-3-(3-methoxypropyloxy)-phenyl]-propyl}-2,2-dimethyl-1,3-oxazolidine

Participants

Reaction Conditions

Reaction Steps

106 μl of 4-methyl-morpholine, 66 mg of 2-aminoisobutyric acid amide hydrochloride and 91 mg of O-benztriazol-1-yl-N,N,N','-tetramethyluronium hexafluorophosphate (HBTU) are added in succession to 119 mg of 3-tert-butoxycarbonyl-5(S)-(2(S)-carboxy-3-methyl-butyl)-4(S)-{2(S)-isopropyl-3-[4-methoxy-3-(3-methoxypropyloxy)-phenyl]-propyl}-2,2-dimethyl-1,3-oxazolidine (Example 124 c) in 8 ml of dimethylformamide. The reaction mixture is stirred for 8 days at 40° C. The mixture is concentrated by evaporation and the residue is partitioned between ethyl acetate and saturated sodium chloride solution. The organic phases are concentrated by evaporation and the residue is purified by means of FC (60 g of silica gel, dichloromethane/methanol=95:5). The title compound is obtained: Rf (dichloromethane/methanol=95:5)=0.30.

Provenance & Evidence