Studies on cerebral protective agents. IV: Synthesis of novel 4-arylpyridine and 4-arylpyridazine derivatives with anti-anoxic activity

In a search for new cerebral protective agents, a series of 4-(3- or 4-nitrophenyl)-6-phenylpyridines (or pyridazines) and 2-(3-nitrophenyl)-6-phenylpyridines, possessing an amino moiety at the C-3 position of the pyridine (or pyridazine) ring, were synthesized through the corresponding novel 1,4-dihydro derivatives and tested for anti-anoxic (AA) activity in mice. Four compounds (2c, 2f, 3a, 4a) possessed significant AA activity at a dose of 32 mg/kg, i.p. These results suggest that four-atom linkages between the C-3 position of the pyridine (or pyridazine) ring and the nitrogenous basic moiety also seems to be a prerequisite for the expression of AA activity.