4 g (7.85 mmol) of [6-hydroxy-2-(4-hydroxyphenyl)benzo[b]thien-3-yl][4-[2-(1-piperidinyl)ethoxy]phenyl]methanone hydrochloride was suspended in 250 ml of anhydrous tetrahydrofuran and 3 g (30 mmol) of triethylamine was added. The reaction mixture was stirred for 15 minutes at room temperature and under nitrogen. 2.77 g (32.6 mmol) of isopropylisocyanate was added. After 24 hours, the reaction was checked by thin layer chromatography for completeness and was not complete. An additional 10.8 g (130.4 mmol) of the isocyanate was added and the reaction was allow to continue for another 96 hours. The desired compound was isolated substantially according to the procedures described in Example 19 to afford 4.01 g of the title compound as a tan amorphous powder.
