Diisopropyl azodicarboxylate (0.1 mL) was added to a solution of 8-(1-methyl-4-phenyl-1H-imidazol-5-yl)-9H-purin-6-amine (Example 3) (75 mg), cyclohexanol (0.07 mL) and triphenylphosphine (0.14 g) in THF (4 mL) under an inert atmosphere. After stirring at ambient temperature for 48 hours the reaction mixture was heated at 40° C. for 48 hours and then at 55° C. for 24 hours. The solvent was then evaporated in vacuo to give a brown oil. Purification by preparative LCMS gave the title compound as a white solid (11 mg, 11%);
