4-Methylmorpholine → Acetylalanylalanylleucine benzyl ester

Participants

Reaction Steps

To a stirred solution of acetylalanine (0.03 mole) and N-methylmorpholine (0.03 mole) in dry tetrahydrofuran (200 ml) at -20° to -25° is added isobutyl chloroformate (0.03 mole). After 10 minutes, a suspension of the crude alanylleucine benzyl ester hydrochloride (0.03+ mole) and N-methylmorpholine (0.04 mole) in tetrahydrofuran (25 ml) is added in portions over 1/2 hour. The mixture is allowed to warm to room temperature over a period of 2 hours and stirred overnight. The reaction mixture is evaporated to dryness and the residue is purified by chromatography on silica gel (200 gm) and elution with 10% methanol in chloroform to give acetylalanylalanylleucine benzyl ester.

Provenance & Evidence