1 L87 8-butyl-1-methyl-7-(2-methylphenyl)-1h-imidazo[2,1-f]purine-2,4(3h,8h)-dione 1.000 2 L90 8-butyl-1-methyl-7-(5-methyl-1h-indazol-4-yl)-1h-imidazo[2,1-f]purine-2,4(3h,8h)-dione 0.897