[OH:1][CH:2]1[CH2:7][CH2:6][N:5]([C:8]([O:10][CH2:11][C:12]2[CH:17]=[CH:16][C:15]([N+:18]([O-:20])=[O:19])=[CH:14][CH:13]=2)=[O:9])[CH2:4][CH2:3]1.[CH3:21][S:22](Cl)(=[O:24])=[O:23].C(N(CC)CC)C>C(Cl)Cl>[CH3:21][S:22]([O:1][CH:2]1[CH2:7][CH2:6][N:5]([C:8]([O:10][CH2:11][C:12]2[CH:17]=[CH:16][C:15]([N+:18]([O-:20])=[O:19])=[CH:14][CH:13]=2)=[O:9])[CH2:4][CH2:3]1)(=[O:24])=[O:23]To a solution of 4-hydroxy-1-(p-nitrobenzyloxycarbonyl)piperidine (2.96 g, 14.8 mmol) (obtained as described in Reference Example 51(1)) in methylene chloride (90 ml) were added methanesulfonyl chloride (1.15 ml, 14.8 mmol) and triethylamine (2.07 ml, 14.8 mmol) in an ice bath. The reaction mixture was brought to room temperature in 10 minutes, and then stirred for 6 hours. After checking the completion of the reaction, the reaction mixture was partitioned between ethyl acetate and saturated aqueous sodium hydrogencarbonate solution. The organic layer was washed with saturated aqueous sodium chloride solution, dried over anhydrous sodium sulfate, filtered and concentrated under reduced pressure. The obtained residue was recrystallized from a solution of n-hexane:ethyl acetate (1:1) to afford 4-methanesulfonyloxy-1-(p-nitrobenzyloxycarbonyl)piperidine (3.31 g, yield 87%) as pale yellow crystals.
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