[N:1]1([C:11]([O:13][C:14]([CH3:17])([CH3:16])[CH3:15])=[O:12])[CH2:6][CH2:5][O:4][CH:3]([C:7](OC)=[O:8])[CH2:2]1.[BH4-].[Li+].O>O1CCCC1>[OH:8][CH2:7][CH:3]1[O:4][CH2:5][CH2:6][N:1]([C:11]([O:13][C:14]([CH3:17])([CH3:16])[CH3:15])=[O:12])[CH2:2]1The crude product from step (i) (62.6 mmol) was dissolved in dry tetrahydrofuran (THF) (100 ml) and added dropwise at 0° C. to a suspension of lithium borohydride (2.50 g, 115 mmol) in dry THF (100 ml). The mixture was allowed to attain room temperature over night. Water (10 ml) was added and after stirring for 1 h the mixture was concentrated. The residue was partitioned between ethyl acetate and water. The organic phase was washed with 0.5 M hydrochloric acid, saturated sodium hydrogen carbonate and water. Drying over magnesium sulfate and concentration gave the title compound as a crude product (13.3 g).
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