1-Iodoethyl isopropyl carbonate → 1-(isopropoxycarbonyloxy)ethyl (5R,6S)-6-((1R)-1-hydroxyethyl)-2-(imidazo[5,1-b]thiazol-3-yl)-1-carbapen-2-em-3-carboxylate

Participants

Reaction Conditions

Reaction Steps

To a solution of 48 mg of sodium (5R,6S)-6-((1R)-1-hydroxyethyl)-2-(imidazo[5,1-b]thiazol-3-yl)-1-carbapen-2-em-3-carboxylate in 1 ml of DMF was added 73 mg of 1-(isopropoxycarbonyloxy)ethyl iodide under the atmosphere of argon at −20° C., and the mixture was stirred for 3 hours during which the temperature was raised up to −10° C. The reaction mixture was extracted twice with 20 ml of ethyl acetate, and washed twice with 10 ml of semi-saturated aqueous saline. The organic layer was dried over anhydrous magnesium sulfate, filtered and concentrated under reduced pressure to a volume of 2 ml. The residue thus obtained was purified by column chromatography on silica gel (chloroform:methanol=9:1) and on Sephadex LH-20 (dichloromethane:methanol=1:1) in this sequence to give the title compound in a yield of 22 mg.

Provenance & Evidence