Phthalazine derivatives attached to amino acid derivatives were synthesized with high yields. The reaction of phthalazine derivatives with different phthalyl and tosylamino acids such as glycine, alanine, phenylalanine, valine, serine, and threonine in the presence of N,N-dicyclo hexylcarbodiimide (DCC) as a dehydrating agent reagent yielded high yields of the afforded compounds. Phthalylamino acids derivatives were obtained by deprotection of phthalazine derivatives, with the latter heating with hydrazine hydrate. The chemical struc- tures of all phthalazine derivatives were affirmed by elemental analysis and spec- tral data (IR, MS, 1HNMR, and 13C NMR). Screening out and estimation of the synthesized derivatives for their cytotoxic and antioxidant activity were done, and most of them showed powerful activity in comparison with standard drugs.