[OH:1][C:2]1[CH:7]=[CH:6][C:5]([CH2:8][CH2:9][C:10]([OH:12])=[O:11])=[CH:4][C:3]=1[C:13](=[O:22])[CH2:14][CH2:15][C:16]1[CH:21]=[CH:20][CH:19]=[CH:18][CH:17]=1.[Br:23]N1C(=O)CCC1=O>CN(C=O)C.CCOCC>[Br:23][C:7]1[CH:6]=[C:5]([CH2:8][CH2:9][C:10]([OH:12])=[O:11])[CH:4]=[C:3]([C:13](=[O:22])[CH2:14][CH2:15][C:16]2[CH:17]=[CH:18][CH:19]=[CH:20][CH:21]=2)[C:2]=1[OH:1]The carboxylic acid 209, for example 3-[4-Hydroxy-3-(3-phenyl-propionyl)-phenyl]-propionic acid, (1.04 gm, 3.4 g mmol) was dissolved in DMF (7 mL) and N-bromosuccinimide (0.65 g, 3.66 mmol) was added to the solution. The mixture was stirred at ambient temperature for 2.5 h, diluted with ether and the organic layer was separated and washed with water and brine and then filtered through a pad of magnesium sulfate and concentrated. The residue was purified by flash chromatography (3.5:1.5:0.1 of hexane:ethyl acetate:acetic acid) to give 0.5 g of 3-[3-bromo-4-hydroxy-5-(3-phenyl-propionyl)-phenyl]-propionic acid 210 as a yellow-brown oil.
読み込み中…