Diisopropylethylamine → HCID 131725311, compound

Participants

Reaction Steps

To a solution of 3-acetylthio-1-[4-(3-methoxyazetidine-1-carbonyl)-1,3-thiazol-2-yl]azetidine (350 mg, 1.07 mmol) (obtained as described in Reference Example 31) in dimethylformamide (18 ml) was added hydrazine acetate (118 mg, 1.28 mmol) at room temperature under an atmosphere of nitrogen and the mixture was stirred for 1 hour. After checking the completion of the reaction, a solution of p-nitrobenzyl (1R,5S,6S)-2-(diphenylphosphoryloxy)-6-[(R)-1-hydroxyethyl]-1-methylcarbapen-2-em-3-carboxylate (636 mg, 1.07 mmol) in acetonitrile (32 ml) was added dropwise to the resulting mixture in an ice bath under an atmosphere of nitrogen, followed by the addition of diisopropylethylamine (746 μl, 4.28 mmol). The mixture was stirred for 6 hours while gradually raising the temperature to room temperature. After checking the completion of the reaction, ethyl acetate and saturated aqueous sodium hydrogencarbonate solution were added to the reaction mixture. The resulting mixture was shaken in a separatory funnel and the ethyl acetate layer was separated, washed with 10% aqueous sodium chloride solution and saturated aqueous sodium chloride solution, dried over anhydrous sodium sulfate, filtered and concentrated under reduced pressure. The residue was purified by chromatography on a silica gel column using ethyl acetate: methanol (95:5 and 9:1) as the eluant to afford p-nitrobenzyl (1R,5S,6S)-2-{1-[4-(3-methoxyazetidine-1-carbonyl)-1,3-thiazol-2-yl]azetidin-3-yl}thio-6-[(R)-1-hydroxyethyl]-1-methylcarbapen-2-em-3-carboxylate (636 mg, yield 94%) as a pale yellow solid.

Provenance & Evidence