β-aroylacrylic acid 2 condensed with hydrazines and hydroxylamine hydrochloride. Simultaneous cyclization of the condensed products yields pyridazinones and Oxazinone. The behaviour of the resulting pyridazinone toward formaldehyde/ piperidine, ethyl chloroacetate, chloroacetic acid, benzene sulfonyl chloride, bromine /acetic acid and aromatic aldehydes has also been studied. However, the reactions of the chloro derivative resulting from the reaction of pyridazinone with POCl3 toward hydrazines, thiourea, sodium azide, aromatic amines and sulfa compounds have also been taken into consideration. The antitumor activity of some of the synthesized compounds were tested.