Acetic Acid → p-nitrobenzyl (1R,5S,6S)-2-{1-[4-(carbamoylmethyl-carbamoyl)-1,3-thiazol-2-yl]azetidin-3-yl}thio-6-[(R)-1-hydroxyethyl]-1-methylcarbapen-2-em-3-carboxylate

Participants

Reaction Steps

To a solution of p-nitrobenzyl (1R,5S,6S)-2-{1-[4-(carbamoylmethyl-carbamoyl)-1,3-thiazol-2-yl]azetidin-3-yl}thio-6-[(R)-1-t-butyldimethylsilyloxyethyl]-1-methylcarbapen-2-em-3-carboxylate (428.6 mg, 0.6 mmol) (obtained as described in Reference Example 45(2)) in tetrahydrofuran (21 ml) were added acetic acid (0.11 ml, 1.9 mmol) and 1 M tetrabutylammonium fluoride in tetrahydrofuran solution (1.8 ml, 1.8 mmol) in an ice bath and the mixture was stirred at room temperature for 3 days. After checking the completion of the reaction, ethyl acetate and saturated aqueous sodium hydrogencarbonate were added to the reaction mixture. The resulting mixture was shaken in a separatory funnel and the ethyl acetate layer was separated, washed with saturated aqueous sodium chloride solution, dried over anhydrous magnesium sulfate, filtered and concentrated under reduced pressure. The residue was purified by chromatography on a silica gel column (eluant: ethyl acetate: methanol (8:1)) to afford p-nitrobenzyl (1R,5S,6S)-2-{1-[4-(carbamoylmethyl-carbamoyl)-1,3-thiazol-2-yl]azetidin-3-yl}thio-6-[(R)-1-hydroxyethyl]-1-methylcarbapen-2-em-3-carboxylate (310.5 mg, yield 85%) as a pale yellow solid.

Provenance & Evidence