All
 D03 Heterocyclic Compounds D006571 +
 D03.438 Heterocyclic Compounds, 2-Ring D006574 +
 D03.438.759 Purines D011687 +
 D03.438.759.758 Purinones D011688 +
 D03.438.759.758.824 Xanthines D014970 +
 D03.438.759.758.824.751 Theophylline D013806 +
 D03.438.759.758.824.751.075 Aminophylline D000628 
 D03.438.759.758.824.751.162 Dimenhydrinate D004111 
 D03.438.759.758.824.751.250 Dyphylline D004400 
 D03.438.759.758.824.751.950 Xanthinol Niacinate D014971 
 D03.438.759.758.824.751.500 1-Methyl-3-isobutylxanthine D015056