[NH2:1][C:2]1[CH:7]=[CH:6][C:5]([CH:8]([CH3:13])[C:9]([O:11]C)=[O:10])=[C:4]([F:14])[CH:3]=1.[C:15]1(=O)[CH2:20][CH2:19][CH2:18][CH2:17][CH2:16]1.[BH3-]C#N.[Na+]>CO.C(O)(=O)C>[CH:15]1([NH:1][C:2]2[CH:7]=[CH:6][C:5]([CH:8]([CH3:13])[C:9]([OH:11])=[O:10])=[C:4]([F:14])[CH:3]=2)[CH2:20][CH2:19][CH2:18][CH2:17][CH2:16]1A solution of compound (7) (1.50 g, 7.6 mmol), cyclohexanone (1.57 mL, 15.2 mmol), and NaBH3CN (0.96 g, 15.2 mmol) in methanol (10 mL) and acetic acid (0.2 mL) was allowed to undergo conventional reactions, followed by the same reactions and treatments as those in Example 3. The obtained crude product was subjected to silica gel column chromatography and elution with an n-hexane/ethyl acetate (4:1) solution followed by conventional hydrolysis to give 1.37 g (65%) of compound (11b) of interest as brown powder.
Loading…
