6-Thio-8-[(4'-pyridylmethyl)thio]theophylline 6493-45-4 NSC98000 Theophylline, 8-[(4-pyridylmethyl)thio]-6-thio- Uric acid, 1,3-dimethyl-8-[(4-pyridylmethyl)thio]-6-thio-