Put 100 mg (0.27 mmol) (+)-1-{[5-(4-methoxyphenyl)-6-phenylfuro[2,3-d]pyrimidin-4-yl]amino}-propan-2-ol with 170 mg (1.33 mmol) acrylic acid tert.-butyl ester and 18.1 mg (0.053 mmol) tetra-n-butylammonium hydrogensulphate in 2 ml dichloromethane and cool to 0° C. Then add 250 μl 50% sodium hydroxide solution and stir the mixture vigorously at 0° C. for 1 h. Leave to return to RT and continue stirring overnight at RT. Then dilute with dichloromethane and water. Acidify with 10% citric acid solution and separate the phases. Re-extract the aqueous phase once with dichloromethane. Combine the organic phases, wash once with satd. sodium chloride solution, dry over magnesium sulphate and concentrate by evaporation. Dissolve the residue thus obtained in 2.5 ml dichloromethane, add 600 μl trifluoroacetic acid and stir for a further 2 h at RT. Then concentrate by evaporation and purify the residue by chromatographing twice on a silica-gel thick-layer plate (solvent: dichloromethane/methanol 9:1). Extract the product zone with dichloromethane/methanol 9:1. After concentrating by evaporation and drying, 38 mg (42.8% of theor.) of the target compound is obtained.
