Ethanol → (4S)-4-[(tert-Butoxycarbonyl)amino]-5-ethoxy-5-oxopentanoic acid

Participants

Reaction Conditions

Reaction Steps

Boc-Glu (OBzl)-OH, 1.01 g (3.0 mmol), 620 mg (3.1 mmol) of N,N-dicyclohexylcarbodiimide (DCC) and 475 mg (3.1 mmol) of 1-hydroxybenzotriazole monohydrate (HOBt.H2O) were suspended in 12 ml of methylene chloride. The suspension was cooled to 0° C. and 175 μl of ethyl alcohol was added thereto. After reverting to room temperature, stirring was continued overnight. The mixture was extracted with ethyl acetate/water. After the organic layer was washed with aqueous saturated sodium chloride solution (brine), sodium sulfate was added thereto and dried. The organic layer was concentrated under reduced pressure. The resulting residue was dissolved in 12 ml of methanol, and 100 mg of 10% Pd/C was added to the solution. The mixture was stirred in a hydrogen atmosphere overnight and purified in accordance with the purification step A to give the crude product of the title compound.

Provenance & Evidence