Sodium hydroxide (2 N, 5.0 mL) 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 (1.0g, 1.26 mmol), methyl alcohol (10 ml) and tetrahydrofuran (10 mL). The reaction mixture was stirred at room temperature for 1 hour, 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 2:1) gave white solid (0.82 g, 74% yield): mp 130-132° C.; MS m/e 797 (M+);
