10.1021/acs.jmedchem.6b01565.s007 Ping Wang Ping Wang Mohamed S. A. Elsayed Mohamed S. A. Elsayed Caroline B. Plescia Caroline B. Plescia Azhar Ravji Azhar Ravji Christophe E. Redon Christophe E. Redon Evgeny Kiselev Evgeny Kiselev Christophe Marchand Christophe Marchand Olga Zeleznik Olga Zeleznik Keli Agama Keli Agama Yves Pommier Yves Pommier Mark Cushman Mark Cushman Synthesis and Biological Evaluation of the First Triple Inhibitors of Human Topoisomerase 1, Tyrosyl–DNA Phosphodiesterase 1 (Tdp1), and Tyrosyl–DNA Phosphodiesterase 2 (Tdp2) American Chemical Society 2017 Tdp 2 inhibition Tdp 2 cancer cells vs 7- azaindenoisoquinolines cancer cell cultures PBMC Tdp 2. Molecular modeling Tdp 2. Enzyme γ- H 2AX foci formation lymphoblastic leukemia CCRF-CEM cells DNA damage lactam side chain topoisomerase inhibitors First Triple Inhibitors 2017-04-18 18:34:00 Dataset https://acs.figshare.com/articles/dataset/Synthesis_and_Biological_Evaluation_of_the_First_Triple_Inhibitors_of_Human_Topoisomerase_1_Tyrosyl_DNA_Phosphodiesterase_1_Tdp1_and_Tyrosyl_DNA_Phosphodiesterase_2_Tdp2_/4887071 Tdp1 and Tdp2 are two tyrosyl–DNA phosphodiesterases that can repair damaged DNA resulting from topoisomerase inhibitors and a variety of other DNA-damaging agents. Both Tdp1 and Tdp2 inhibition could hypothetically potentiate the cytotoxicities of topoisomerase inhibitors. This study reports the successful structure-based design and synthesis of new 7-azaindenoisoquinolines that act as triple inhibitors of Top1, Tdp1, and Tdp2. Enzyme inhibitory data and cytotoxicity data from human cancer cell cultures establish that modification of the lactam side chain of the 7-azaindenoisoquinolines can modulate their inhibitory potencies and selectivities vs Top1, Tdp1, and Tdp2. Molecular modeling of selected target compounds bound to Top1, Tdp1, and Tdp2 was used to design the inhibitors and facilitate the structure–activity relationship analysis. The monitoring of DNA damage by γ-H2AX foci formation in human PBMCs (lymphocytes) and acute lymphoblastic leukemia CCRF-CEM cells documented significantly more DNA damage in the cancer cells vs normal cells.