Cesium carbonate → 4-{(S)-2-[(4-Benzyloxycarbonylmethoxy-7-methyl-naphthalene-2-carbonyl)-amino]-4-tert-butoxycarbonyl-butyryl}-piperazine-1-carboxylic acid butyl ester

Participants

Reaction Steps

To a solution of 1.0 g 4-{(S)-4-tert-Butoxycarbonyl-2-[(4-hydroxy-7-methyl-naphthalene-2-carbonyl)-amino]-butyryl}-piperazine-1-carboxylic acid butyl ester in 12 ml of DMF, 645 mg of cesium carbonate and 447 mg of Bromo-acetic acid benzyl ester were added and the reaction mixture was stirred for 2 h at RT. Then, the reaction mixture was diluted with water and extracted with ethyl acetate. The organic phase was dried over MgSO4 and the solvents were removed under reduced pressure. The isolated crude product was pure enough for the next reaction step. Yield: 710 mg.

Provenance & Evidence