Collect. Czech. Chem. Commun. 1990, 55, 2257-2269
https://doi.org/10.1135/cccc19902257

3,7-Dialkyl-8-alkyl- or -aryl-3,7-dihydropurine-2,6-diones

Alfonz Rybára, Dušan Hesekb, Fridrich Szemesb, Juraj Alföldia and Marian Tegzab

a Institute of Chemistry, Slovak Academy of Sciences, 842 38 Bratislava
b Drug Research Institute, 900 01 Modra

Abstract

3,7-Dialkyl-8-alkyl- or -aryl-3,7-dihydropurine-2,6-diones XII-XIV were synthesized from 5-alkylamino-6-amino-1-alkyl-2,4(1H,3H)-pyrimidinediones VII-IX by three methods: the first is based upon an acid catalyzed cyclization of the starting derivatives VII-IX with orthoesters of carboxylic acids in dimethylformamide. In the second and third methods the 5-((N-acyl)(N-alkyl)amino) derivatives X, XI, obtained by acylation of VII-IX were cyclized either in aqueous solution of alkali metal hydroxides, or in dimethylformamide in the presence of alkali metal hydroxides, or in dimethylformamide in the presence of alkali metal carbonates. Intermediates VII-IX were prepared from 6-amino-1-alkyl-2,4(1H,3H)-pyrimidinediones I-III via the corresponding 5-bromo derivatives IV-VI and by their aminolysis with the appropriate alkylamines.