Prepared according to the method described in Example 33a) from toluene (3 ml), aqueous sodium carbonate (2 M, 0.9 ml), ethanol (1.0 ml), 3-bromo-N-phenylbenzamide (0.48 g), (±)-4-[4-(3-pyridyl)-2-(tert-butyldimethylsilyloxy)butoxy]benzeneboronic acid (0.7 g) and tetrakis(triphenylphosphine)palladium(0) (50 mg) with heating at 120° C. for 5 hours. The residue obtained after work up was purified by column chromatography over silica eluting with ethyl acetate:hexane (1:1) to give a colourless oil which was desilylated by treatment with tetrabutylammonium fluoride (0.7 ml; 1 M in tetrahydrofuran) in tetrahydrofuran at 0° C. After stirring at this temperature for 5 minutes a saturated solution of brine (5 ml) was added and the organic phase separated. The aqueous phase was extracted with ethyl acetate (20 ml). The combined organic phases were washed with brine, dried over anhydrous magnesium sulfate, filtered and concentrated under reduced pressure. The residue was purified by column chromatography over silica eluting with ethanol:dichloromethane (1:19) to give the title compound as a colourless solid (0.09 g).
