Theophylline-7-acetaldehyde; 1,2,3,6-Tetrahydro-1,3-dimethyl-2,6-dioxopurine-7-acetaldehyde; 7-(Formylmethyl)theophylline; 7-Theophyllineacetaldehyde; 2-(1,3-dimethyl-2,6-dioxo-1,2,3,6-tetrahydro-7H-purin-7-yl)acetaldehyde