[CH3:1][C:2]1[O:6][N:5]=[C:4]([C:7]2[CH:12]=[CH:11][CH:10]=[CH:9][N:8]=2)[C:3]=1[CH2:13][OH:14].[CH3:15][O:16][C:17]([C:19]1[O:23][NH:22][C:21](=O)[CH:20]=1)=[O:18].C1(P(C2C=CC=CC=2)C2C=CC=CC=2)C=CC=CC=1.N(C(OCC)=O)=NC(OCC)=O>C1COCC1>[CH3:15][O:16][C:17]([C:19]1[O:23][N:22]=[C:21]([O:14][CH2:13][C:3]2[C:4]([C:7]3[CH:12]=[CH:11][CH:10]=[CH:9][N:8]=3)=[N:5][O:6][C:2]=2[CH3:1])[CH:20]=1)=[O:18]To a solution of (5-methyl-3-pyridin-2-yl-isoxazol-4-yl)-methanol (465 mg, 2.44 mmol) in THF (10 mL) was added 3-oxo-2,3-dihydro-isoxazole-5-carboxylic acid methyl ester (350 mg, 2.45 mmol) and triphenylphosphine (769 mg, 2.93 mmol) at 0° C. under an argon atmosphere. Then diethyl azodicarboxylate (˜40% in toluene, 1.23 mL, 2.68 mmol) was added and the reaction mixture was stirred for 1 h at 0° C. and then overnight at room temperature. Concentration and purification by chromatography (silica, heptane:ethyl acetate=4:1 to 1:4) afforded the title compound (443 mg, 57%) as a white solid. MS: m/e=316.2 [M+H]+.
불러오는 중…