Synthesis of a novel ring-expanded xanthine analogue and several methyl or benzyl derivatives containing the 5:7-fused imidazo[4,5-e][1,2,4]triazepine ring system

Article abstract of DOI:10.1055/s-1990-27103

Syntheses of 3,4,6,7-tetrahydroimidazo[4,5-e][1,2,4]triazepine-5,8-dione (1a) and its 3- and/or 7-methyl/benzyl substituted derivatives 1b-1e are reported. The structure of 1c is confirmed by single-crystal X-ray diffraction analysis.