4-Methylmorpholine → 5(S)-[1(S)-(Boc-amino)-2-phenylethyl]-3(R)-phenylmethyldihydrofuran-2-(3H)one

Participants

Reaction Steps

A solution of 250 mg of 5(S)-(Boc-amino)-4(S)-tert-butyldimethylsilyloxy)-6-phenyl-(R)-phenylmethyl-hexanoic acid in 3 ml of DMF with 230.5 mg of BOP, 70.4 mg of HOBT and 182.6 ml of N-methylmorpholine is stirred for 30 minutes at room temperature in approximately 2 ml of DMF, and then 189.5 mg of H-(L)-Val-(L)-Phe-morpholin-4-ylamide [preparation, see under 1 k) to 1 n)] are added. After 16 hours at room temperature, the reaction mixture is concentrated by evaporation and the residue is partitioned between three portions of ethyl acetate, water, saturated sodium hydrogen carbonate solution, water and brine, and the organic phases are dried with sodium sulfate and concentrated by evaporation, yielding the title compound as a crude product; TLC Rf (A)=0.24; FAB-MS (M+H)+ =843.

Provenance & Evidence