SYNTHESIS, ANTICANCER ACTIVITY AND MOLECULAR DOCKING STUDY OF NOVEL 1, 3-DIHETEROCYCLES INDOLE DERIVATIVES

Objective : The present work aimed to synthesize some new 1, 3-diheterocyles indolyl derivatives and study their cytotoxic activity. In addition, explore the probability of the most promising antiproliferative compounds to inhibit TopoI enzyme theoretically via molecular docking study. Methods : Reaction of ethyl 2-(3-formyl-1 H -indol-1-yl)acetate (1) with 2-cyanoacetic acid hydrazide, 3-amino-5-pyrazolone and 2'-acetyl-2-cyanoacetohydrazide in an equal molar ratio led to the formation of compounds 2, 6, 8 and 10, respectively, which in turn reacted with another molecule of 2-cyanoacetic acid hydrazide and/or 3-amino-5-pyrazolone (1:1 molar ratio) to give novel series of 1,3-dipyrazole indole derivatives 3, 7, 9 and 11, respectively. On the other hand, Knoevenagel condensation of 1 with malononitrile gave ethyl 2-(3-(2, 2-dicyanovinyl)-1 H -indol-1-yl) acetate (11). Reaction of 11 with 2-cyanoacetic acid hydrazide, 3-amino-5-pyrazolone, hydrazine hydrate, urea, thiourea and/or guanidine yielded 1, 6-diaminopyridine 12, pyrano(2,3- c )pyrazole 14, pyrazole 16 and pyrimidine derivatives 18a-c, respectively. Reaction of the latter compounds with 3-amino-5-pyrazolone furnished a novel series of 1, 3-diheterocycle indole derivatives 13, 15, 17 and 19a-c, respectively. Ten new target compounds 3, 6, 8, 10, 13, 15, 17 and 19a-c were tested for in vitro antiproliferative activity against A-549, MCF7, HCT-116 and HEPG2 cancer cell lines. In addition, molecular docking study of the most promising antiproliferative compounds against human DNA Topoisomerase I (PDB ID: 1T8I) theoretically is discussed. Results : Compounds 3, 6, 8 and 17 showed potent in vitro antiproliferative activity. Docking scores of the latter compounds were observed better than co-crystalline ligand. Conclusion : Further work is recommended to confirm the inhibition of TopoI in a specific bioassay.