(3S,4R)-3-[(1R)-1-(t-butyldimethylsilyloxy)ethyl]-4-{(1R)-1-methyl-2-[7-(pyridin-3-yl)carbonylimidazo[5,1-b]thiazol-2-yl]-2-oxoethyl}-1-[4-nitrobenzyloxycarbonyl(triphenylphosphoranylidene)-methyl]azetidin-2-one → (4-nitrobenzyl) (1S,5R,6S)-6-[(1R)-1-(t-butyldimethylsilyloxy)ethyl]-2-[7-(pyridin-3-yl)carbonylimidazo[5,1-b]thiazol-2-yl]-1-methylcarbapen-2-em-3-carboxylate

Participants

Reaction Steps

A solution of 54.6 mg of (3S,4R)-3-[(1R)-1-(t-butyldimethylsilyloxy)ethyl]-4-{(1R)-1-methyl-2-[7-(pyridin-3-yl)carbonylimidazo[5,1-b]thiazol-2-yl]-2-oxoethyl}-1-[4-nitrobenzyloxycarbonyl(triphenylphosphoranylidene)methyl]azetidin-2-one in 2 ml of toluene was heated under reflux for 2.5 hr. The solvent was removed by evaporation, and the residue was purified by thin layer chromatography (developed with 5% methanol/ethyl acetate) to give 28.3 mg of (4-nitrobenzyl) (1S,5R,6S)-6-[(1R)-1-(t-butyldimethylsilyloxy)ethyl]-2-[7-(pyridin-3-yl)carbonylimidazo[5,1-b]thiazol-2-yl]-1-methylcarbapen-2-em-3-carboxylate.

Provenance & Evidence