C([O:3][C:4]([C:6]1[C:7]([C:12]2[CH:17]=[CH:16][N:15]=[CH:14][CH:13]=2)=[N:8][O:9][C:10]=1[CH3:11])=O)C.[H-].[Al+3].[Li+].[H-].[H-].[H-].O.[OH-].[Na+]>C1COCC1>[CH3:11][C:10]1[O:9][N:8]=[C:7]([C:12]2[CH:17]=[CH:16][N:15]=[CH:14][CH:13]=2)[C:6]=1[CH2:4][OH:3]To a solution of 5-methyl-3-pyridin-4-yl-isoxazole-4-carboxylic acid ethyl ester (7.1 g, 17.3 mmol) in THF (350 mL) was added at 5° C. lithium aluminum hydride (635 mg, 16.7 mmol). After stirring for 2 h at this temperature further lithium aluminum hydride (318 mg, 8.4 mmol) was added and stirred for 1 h at 5° C. Water (1.9 mL) was added carefully followed by aqueous sodium hydroxide (15%, 1.9 mL) and water (0.54 mL). The resulting suspension was stirred for 15 min at ambient temperature and filtered over Hyflo®. Concentration and purification by chromatography (SiO2, heptane:ethyl acetate=50:50 to 0:100) afforded the title compound (2.15 g, 65%) as a light yellow solid. MS: m/e=191.2 [M+H]+.
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