1. Akhila, J. S., Shyamjith, Deepa, and Alwar, M. C., Acute toxicity studies and determination of median lethal dose. Curr. Sci., 93, 917–920 (2007).
2. Ashour, F. A., Yousry, A. H., and Hamouda, A. F., Synthesis of some 4-arylideneamino-5-mercapto-1,2,4-triazole, 1,2,4-triazolothiadiazole and 1,2,4-triazolothiadiazine derivatives of theophylline as antimicrobial agents. Alex. J. Pharm. Sci., 7, 127–130 (1993).
3. Baraldi, P. G., Fruttarolo, F., Tabrizi, M. A., Romagnoli, R., and Preti, D., Novel 8-heterocyclic xanthine derivatives in drug development — an update. Expert Opin. Drug Discov., 2, 1161–1183 (2007).
4. Baziard-Mouysset, G., Rached, A., Younes, S., Tournaire, C., Stigliani, J. L., Payard, M., Yavo, J. C., and Advenier, C., Synthesis and in vitro bronchospasmolytic activity of 8-aryl, heteroaryl or arylalkyl theophyllines. Eur. J. Med. Chem., 30, 253–260 (1995).
5. Berk, B., Akgün, H., Erol, K., Sirmagül, B., Gao, Z.-G., and Jacobson, K. A., New 8-substituted xanthine derivatives as potent bronchodilators. Farmaco, 60, 974–980 (2005).