135471-73-7 2,5,6,9-Tetrahydro-6,9-di-n-propyl-3H-1,2,4-triazolo(3,4-i)purine-3,5-dione 3H-1,2,4-Triazolo(3,4-i)purine-3,5(2H)-dione, 6,9-dihydro-6,9-dipropyl- 6,9-Dihydro-6,9-dipropyl-3H-1,2,4-triazolo(3,4-i)purine-3,5(2H)-dione