Ethylmorpholine → L-Pyroglutamyl-4-aminobutyric acid tert. butyl ester

Participants

Reaction Steps

1.3 ml of N-ethylmorpholine and 3.08 g of L-pyroglutamic acid 2,4,5-trichlorophenyl ester were added to a solution of 1.95 g (10 mmols) of 4-aminobutyric acid tert. butyl ester hydrochloride in 20 ml of dimethylformamide. The solution was left overnight at room temperature. It was concentrated, the residue was dissolved in a mixture of ethyle acetate and water, and the ethyl acetate solution was shaken with sodium bicarbonate solution, KHSO4 -solution and NaCl-solution, dried with Na2SO4 and concentrated. The residue was triturated with petroleum ether.

Provenance & Evidence