1-Propyl-3-butyl-8-methylxanthine 1H-Purine-2,6-dione, 3,7-dihydro-3-butyl-8-methyl-1-propyl- 3,7-Dihydro-3-butyl-8-methyl-1-propyl-1H-purine-2,6-dione 81250-24-0