Acetonitrile → Nalpha-(2,6-dichlorobenzoyl)-4-{2-ethoxycarbonylamino-5-(N-formyl-N-methyl-aminomethyl)-benzoylamino}-L-phenylalanine isopropyl ester

Participants

Reaction Conditions

Reaction Steps

To 2.0 g of 2-amino-5-(N-formyl-N-methylamino-methyl)-benzoic acid, there were added 10 mL of acetonitrile and 3.9 mL of pyridine to form a slurry and the latter was cooled to 10° C. To this slurry, there was dropwise added 2.76 mL of ethyl chloro-formate over 5 minutes and then stirred for one hour. After the confirmation of the disappearance of the starting material by HPLC, 1.46 mL of 2-propanol was added to the reaction liquid so that the unreacted ethyl chloroformate was thus decomposed at 25° C. To this reaction liquid, there was added 3.80 g of 4-amino-Nα-(2,6-dichlorobenzoyl)-L-phenylalanine isopropyl ester and the resulting mixture was stirred overnight. Subsequently, 30 mL of 2-propanol was dropwise added to the mixture, followed by the stirring of the mixture at 10° C. for 3 hours. The solid separated was isolated through filtration under reduced pressure, washed with 10 mL of 2-propanol and then dried at 60° C. for 18 hours under reduced pressure to thus give 4.35 g of the intended product as a white crystalline solid.

Provenance & Evidence