Ethyl Acetate → (1R, 5S, 6S)-2-[(3R)-pyrrolidine-2-thion-3-ylthio]-6-[(1R)-1-hydroxyethyl]-1-methylcarbapen-2-em-3-carboxylic acid isobutyryloxymethyl ester

Participants

Reaction Steps

(1R, 5S, 6S)-2-[(3R)-Pyrrolidine-2-thion-3-ylthio]-6-[(1R)-1-hydroxyethyl]-1-methylcarbapen-2-em-3-carboxylic acid potassium salt (0.5 g) is suspended in N,N-dimethylformamide (5 ml). To the suspension is added isobutyryloxymethyl iodide (338 mg) under ice cooling, and the mixture is stirred at the same temperature for 30 minutes. To the reaction mixture is added ethyl acetate, and the mixture is washed with water, dried and concentrated to dryness under reduced pressure. The residue is purified by silica gel flash column chromatography (eluent, chloroform:methanol=20:1) to give (1R, 5S, 6S)-2-[(3R)-pyrrolidine-2-thion-3-ylthio]-6-[(1R)-1-hydroxyethyl]-1-methylcarbapen-2-em-3-carboxylic acid isobutyryloxymethyl ester (0.14 g) as an amorphous powder.

Provenance & Evidence