Potassium carbonate (0.01 g) was added into a mixture of (2R)-2-[4′-(2-benzyl-benzo[b]-thiophen-3-yl)-3,5-dibromo-biphenyl-4-yloxy]-4-(1,3-dioxo-1,3-dihydro-isoindol-2-yl)-butyric acid methyl ester (0.5, 0.063 mmol), methyl alcohol (10 mL), and water (0.5 mL). The reaction mixture was stirred at room temperature for 24 hours, poured into water, acidified with HCl (2 N), and extracted with ethyl ether. The organic extracts were dried over MgSO4. Evaporation and purification by flash chromatography on acidic silica gel (hexanes/EtAOc 4:1) gave white solid (0.32 g, 63% yield): mp 95-97° C; MS m/e 811 (M+);
