C([Li])CCC.Br[C:7]1[CH:12]=[CH:11][CH:10]=[CH:9][N:8]=1.CN(OC)[C:15]([C@@H:17]1[CH2:21][C:20](=[O:22])[N:19]([C@@H:23]([C:25]2[CH:30]=[CH:29][CH:28]=[CH:27][CH:26]=2)[CH3:24])[CH2:18]1)=[O:16].Cl>O1CCCC1>[C:25]1([C@H:23]([N:19]2[CH2:18][C@H:17]([C:15]([C:7]3[CH:12]=[CH:11][CH:10]=[CH:9][N:8]=3)=[O:16])[CH2:21][C:20]2=[O:22])[CH3:24])[CH:26]=[CH:27][CH:28]=[CH:29][CH:30]=1In an atmosphere of nitrogen and at −78° C., n-butyl lithium (1.5 mol/l tetrahydrofuran solution; 13.2 ml, 19.9 mol) was added dropwise to a tetrahydrofuran solution (40 ml) of 2-bromopyridine (1.94 ml, 19.9 mmol), and then the mixture was stirred for 10 minutes. At −78° C., to this was further added dropwise a tetrahydrofuran solution (20 ml) of N-methyl-N-methoxy-[1-(R)-phenylethyl]-5-oxopyrrolidine-3-(R)-carboxamide (3.66 g, 13.2 mmol), and the mixture was stirred for 30 minutes. The reaction solution was mixed with 1 mol/l hydrochloric acid (200 ml), warmed up to room temperature and then extracted with diethyl ether (200 ml×2). The resulting organic layer was washed with saturated brine (100 ml) and dried over anhydrous magnesium sulfate. The solvent was evaporated under a reduced pressure and the residue was applied to a silica gel column chromatography (silica gel 100 g). By eluting with a n-hexane:ethyl acetate system of from (3:1) to (1:1), 1.97 g (52%) of the title Sound was obtained as a light yellow oil.
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