Phosphate → (5R,6S)-6-((1R)-1-hydroxyethyl)-2-(6-methylimidazo[5,1-b]thiazolium-3-yl)-1-carbapen-2-em-3-carboxylate

Participants

Reaction Steps

To a suspension of 100 mg of 4-nitrobenzyl (5R,6S)-6-((1R)-1-hydroxyethyl)-2-(imidazo[5,1-b]thiazol-3-yl)-1-carbapen-2-em-3-carboxylate in 1.5 ml of dry dichloromethane was added 1.37 ml of iodomethane, and the mixture was stirred under the atmosphere of argon in the darkness at room temperature for 24 hours. Unreacted reagent was removed under reduced pressure. The residue thus obtained was dissolved in 4 ml of THF and 4 ml of 1/15 M phosphate buffer (pH 6.8), and 160 mg of 10% Pd-C was added. The reactor was purged with hydrogen, the reaction mixture was stirred at room temperature for 3.5 hours. The catalyst was collected by filtration on Celite and washed with water. The filtrate was washed with ethyl acetate, and purified by column chromatography on DIAION HP-20 and COSMOSEAL 40C18-PREP (water:methanol=20:1) to give 4.8 mg of the title compound.

Provenance & Evidence