200 mg (0.72 mmol) of the compound of Example 4A together with 201 mg (0.87 mmol) of 2-bromo-4-nitroanisole were dissolved in 3.6 ml of dioxane, the mixture was degassed with argon and 16 mg (0.07 mmol) of palladium(II) acetate, 63 mg (0.11 mmol) of xantphos [4,5-bis(diphenylphosphino)-9,9-dimethylxanthene] and 589 mg (1.81 mmol) of caesium carbonate were added. The mixture was heated in a microwave oven (Biotage Initiator, with Dynamic Field Tuning) at 150° C. for 30 min. The reaction was then filtered through kieselguhr, the filtrate was concentrated under reduced pressure and the residue was separated by preparative HPLC (Method 12) into its components. The product-containing fractions were combined and, under reduced pressure, concentrated almost completely. The residue was made alkaline with a little saturated aqueous sodium bicarbonate solution. The precipitate formed was filtered off, washed with water and dried. This gave 210 mg (92% pure, 62% of theory) of the title compound.
