Convenient Synthesis of Some Novel 4-Benzyl-1(2H)-Phthalazinone Derivatives of expected anticancer activity

Series of new synthesized biologically active phthalazinone derivatives were obtained. Starting from the amino acid methyl esters of 4-benzyl-1(2 H )-phthalazinone 2a,b which were synthesized from the aceto hydrazide of 4-benzyl-1(2 H )-phthalazinone 1 via azide coupling method. The hydrazides 3a,b were prepared from hydrazinolysis of corresponding esters 2a,b . N -substituted-2-(4-Benzyl-1-oxo-1H-phthalazin-2-yl)-methyl-acetamide 4a-f and the dipeptides methyl {2-[2-(4-Benzyl-1-oxo-1H-phthalazin-2-yl)-acetylamino]-acetylamino}-alkanoates 6a-c were obtained by the reaction of corresponding hydrazide 3a with amines and amino acid esters respectively via azide coupling method. Similarly; N - substituted - 3 -[2-(4-Benzyl-1-oxo-1H-phthalazin-2-yl)-acetyl amino] propionamide 5a-f and the dipeptides methyl{3-[2-(4-Benzyl-1-oxo-1H-phthalazin-2-yl)-acetylamino]-propionylamino} alkanoates 7a-c were obtained by the reaction of corresponding hydrazide 3b with amines and amino acid esters respectively via azide coupling method