PURINES, PYRIMIDINES, AND CONDENSED SYSTEMS BASED ON THEM. 18. REACTION OF 6,8-DIMETHYLPYRIMIDO[4,5-<i>c</i>]PYRIDAZINE-5,7(6H,8H)-DIONE N₍₂₎-OXIDE WITH ALKYLAMINES

Abstract

Heating 6,8-dimethylpyrimido[4,5-c]pyridazine-5,7(6H,8H)-dione N₍₂₎-oxide (2) with piperidine or morpholine gave a moderate yield of 3-piperidino- and 3-morpholino-6,8-dimethylpyrimido[4,5-c]-pyridazine-5,7(6H,8H)-diones (3a,b). Reaction of N-oxide (2) with ammonia and alkylamines in the presence of an oxidant led to formation of the 3-amino derivatives of 2 and the corresponding desoxy products 3. The latter were also obtained by an independent method by heating 3-chloro-6,8-dimethylpyrimido[4,5-c]pyridazine-5,7(6H,8H)-dione with alkylamines in butanol.

Authors: D. V. Besedin, A. V. Gulevskaya, and A. F. Pozharskii.

English Translation in Chemistry of Heterocyclic Compounds, 2000, 36 (10), pp 1213-1218

http://link.springer.com/article/10.1023/A%3A1002829018667