Purine studies. XVIII. The C- and N-alkylation of theophylline and derivatives

Abstract

Alkylation of theophylline in aqueous alkaline solution with benzyl halides gives, in addition to the expected N7 benzylated derivative, both 8-benzyl- and 7,8-dibenzyl-theophylline. Synthetic routes to these derivatives have been explored and unusual reactivity associated with benzyl groups in some of the intermediates has been demonstrated. Results which do not preclude the possibility that benzyl radicals could be responsible for the 8-benzylation reaction have been obtained.