Intermediate compounds for the manufacture of fused piperazin-2-one derivatives

摘要

Disclosed are processes for the preparation of fused piperazin-2-one derivatives of general formula (I) wherein the groups R¹ to R⁵, A₁ and A₂ have the meanings given in the claims and in the description, particularly the preparation of 7,8-dihydro-5H-pteridin-6-one derivatives and intermediates thereof.