Studies on Quinolizine Derivatives. XVII. Synthesis of Diazacycl-[3.3.3] azine Derivatives. (10)

Abstract

1, 9-Diazacycl [3.3.3] azine derivatives (XII, XIII) were synthesized by the reaction of acetic anhydride or ethoxymethylenemalononitrile with 1-imino-8-methyl-1H-pyrido-[1, 2-c] pyrimidine derivatives, which were obtained by the treatment of dimethyl cyanamidodithiocarboxylate or O-ethyl S-methyl cyanamidothiocarboxylate with 6-methyl-2-pyridineacetate derivatives. By the decarboxylation of XIII, 2-methylthio-1, 9-diazacycl [3.3.3] azine (XV), which was unstable as a free base, was obtained. On the other hand, 2, 3-dihydro-8-methyl-2-oxo-1, 9-diazacycl [3.3.3] azine hydrobromide (XVI) was obtained from the degradation of XVII. The nuclear magnetic resonance (NMR) spectral data suggested that XV may be a 12π-monocyclic antiaromatic compound.