C([O:6][CH2:7][CH:8]1[O:12][N:11]=[C:10]([C:13]2[CH:18]=[CH:17][C:16]([Br:19])=[CH:15][N:14]=2)[CH2:9]1)(=O)CCC>CO>[Br:19][C:16]1[CH:17]=[CH:18][C:13]([C:10]2[CH2:9][C@H:8]([CH2:7][OH:6])[O:12][N:11]=2)=[N:14][CH:15]=1(R,S)-[3-(5-Bromopyridin-2-yl)-4,5-dihydroisoxazol-5-yl]methanol (prepared by hydrolysis of Intermediate 9, 3.1 g) was dissolved in hot methanol (25 ml), it was then separated by chiral column (Chiral Pak AS) eluting with 30%, isopropanol in hexanes. The title compound [(−) isomer, 1.5 g)] which eluted first from the column was collected along with the (+) isomer (second peak, 1.18 g). Chiral HPLC analysis indicated <2% of the (+) isomer was present. [α]D=−125° (c=0.0076 g/ml in methanol).
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