2,6-Dichlorobenzoyl chloride → N-[(2,6-dichlorophenyl)carbonyl]-4-(1,3,6-trimethyl-2,4-dioxo-5-pyrimidinyl)-L-phenylalanine 1-(acetoxy)ethyl ester

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Reaction Steps

To a suspension of 4-(1,3,6-trimethyl-2,4-dioxo-5-pyrimidinyl)-L-phenylalanine 1-(acetoxy)ethyl ester hydrochloride salt (0.723 mmol, 399 mg) and 2,6-dichlorobenzoyl chloride (0.8 mmol, 0.17 g) in dichloromethane (5 mL) was added diisopropylethylamine (3.2 mmol, 0.45 mL) at room temperature. After 5 min, everything went into solution and the clear yellow solution was stirred for 48 h at room temperature. The resulting light brown solution was diluted with dichloromethane (50 mL). The dichloromethane layer was washed successively with 1N hydrochloric acid (2×50 mL), saturated sodium bicarbonate solution (50 mL), and brine solution (50 mL) and was dried over anhydrous magnesium sulfate. Filtration of the drying agent and concentration of the solvent gave the crude product, which was purified by silica gel chromatography using a Biotage (40s) column to afford 0.312 g (67% yield) of N-[(2,6-dichlorophenyl)carbonyl]-4-(1,3,6-trimethyl-2,4-dioxo-5-pyrimidinyl)-L-phenylalanine 1-(acetoxy)ethyl ester as a white solid: mp 168-170° C. ES-HRMS m/e calcd for C27H27Cl2N3O7 (M+Na) 598.1118, found 598.1122.

Provenance & Evidence