Malonate Ion → 3-[(2-chlorophenyl)methyl]-2-propylthio-N-acetylhistidine

Participants

Reaction Conditions

Reaction Steps

Crude 1-(2-chlorophenyl)methyl)-5-chloromethyl-2-propylthio-1H-imidazole hydrochloride (0.3 g, 0.853 mmole) in dimethyl formamide (2 mL) was added to sodium diethyl acetamidomalonate (prepared by introducing sodium hydride (2.84 mmol) to a solution of diethyl acetamidomalonate (0.415 g, 1.91 mmol) in dimethyl formamide (3 mL)). The mixture was stirred under argon at 25° C. for 18 hours, poured into water and the product was extracted into methylene chloride. The water-washed organic extracts were dried and concentrated in vacuo to a light orange product. This crude product was purified over silica gel with 1:1 hexane/ethyl acetate to afford 0.27 g of the malonate addition product. This product was hydrolyzed in 50% aqueous ethanol (20 mL) and sodium carbonate (0.85 g) in water (20 mL) on the steam bath for 3 hours. The reaction mixture was poured into water and extracted with methylene chloride. The washed, dried, concentrated product (0.23 g) was purified by prep TLC on silica gel with a system of 15% methanol in chloroform containing 0.5% of formic acid to provide 0.13 g of 3-[(2-chlorophenyl)methyl]-2-propylthio-N-acetylhistidine as an amorphous solid; m.p. 182°-184° C.

Provenance & Evidence