Starting from methyl-1,4-Dioxo-3-phenyl-3,4-dihydro-1H-phthalazin-2-yl-acetate (2) eighteen newly Phthalazine dione derivatives were synthesized. The starting material 2 was prepared by N-alkylation of 2-phenyl-2,3-dihydrophthalazine-1,4-dione (1) with ethyl chloro acetate under reflux over night. 2-(1,4-dioxo-3-phenyl-3,4-dihydrophthalazin-2(1H)-yl)acetohydrazide (3) was prepared by hydrazinolysis of ester 2 with hydrazine hydrate under reflux. Monopeptide 4a-c were prepared via azide coupling method by coupling of hydrazide 3 with different methyl ester of glycine, β-alanine and L-leucine respectively. The hydrazides 5a-c were prepared by hydrazinolysis of esters 4a-c with hydrazine hydrate respectively. Similarly; dipeptides 6a-i were prepared form coupling of methyl esters of glycine, β-alanine and L-leucine with hydrazides 5a-c via azide coupling method. Schiff’s base hydrazones 7a-i were prepared by condensation of hydrazides 5a-c with different aldehydes such as 4-chlorobenzaldehyde, 4-methoxybenzaldehyde and 4-nitrobenzaldehyde.

The anti-bacterial activities of the synthesized compound were screened in vitro against E.coli, Salmonella and Staphylococcus aureus with comparison to 2-phenyl-2,3-dihydrophthalazine-1,4-dione (1). The results showed that most compounds have activities against E.coli and a little compounds were sensitive to Salmonella but there no significance response to Staphylococcus aureus. Also the anti-cancer activities were assayed and some synthesized phthalazinedione has high activity in inhibition of HEPG2 and MCF-7 cancer cell lines.