A solution of 1-(4-(R)-Methyl-8-methylnon-7-enyl)-3,7-dimethylxanthine (0.48 g, 1.44 mmol), 4-methylmorpholine-N-oxide (0.51 g, 4.38 mmol) and potassium osmate dihydrate (5 mg, 0.015 mmol) in acetone/water 1:2 (9 mL) was stirred for 16 hours. Water (10 mL) and sodium sulfite (1 g) were added and the reaction mixture stirred for 1 hour. The reaction mixture was extracted with dichloromethane (3×30 ml) using dried magnesium sulfate and the solvent evaporated to yield 0.51 g (97% yield) 1-(4-(R)-Methyl-7,8-dihydroxy-8-methylnonyl)-3,7-dimethylxanthine (inventive compound no. 2537R) as a colorless oil.
