英文别名9-(1,3-Dioxolan-2-ylmethyl)-1,3-dimethyl-3,9-dihydro-1H-purine-2,6-dione; Doxofylline Impurity 3; Theophylline Impurity 4; Doxofylline Impurity 3 (Theophylline Impurity 4); Theophylline Impurity 4 (Doxofylline Impurity 3); 9-(1,3-Dioxolan-2-ylmethyl)-1,3-dimethylpurine-2,6-dione