Abstract
1, 2, 3, 4-Tetrahydro-7-phenylpyrido[3, 4-d]pyridazine-1, 4-dione (18) and 2-phenyl-5, 6, 7, 8- tetrahydropyrido[2, 3-d]pyridazine-5, 8-dione (22) were converted to the corresponding dichlorides, which were allowed to react with amines to give 1, 4-bis(substitutedamino)-7-phenylpyrido[3, 4-d]pyridazines (9) and 2-phenyl-5, 8-bis(substituted amino)pyrido[2, 3-d]-pyridazines (10). Among these compounds, 1, 4-dimorpholino-7-phenylpyrido[3, 4-d]pyridazine (5a) and 2-phenyl-5, 8-bis(isopropylamino)pyrido[2, 3-d]pyridazine (6c) showed a strong diuretic activity.
