124340-92-7Relevant academic research and scientific papers
Resistance-modifying agents. 9. Synthesis and biological properties of benzimidazole inhibitors of the DNA repair enzyme poly(ADP-ribose) polymerase
White,Almassy,Calvert,Curtin,Griffin,Hostomsky,Maegley,Newell,Srinivasan,Golding
, p. 4084 - 4097 (2007/10/03)
The nuclear enzyme poly(ADP-ribose) polymerase (PARP) facilitates the repair of DNA strand breaks and is implicated in the resistance of cancer cells to certain DNA-damaging agents. Inhibitors of PARP have clinical potential as resistance-modifying agents capable of potentiating radiotherapy and the cytotoxicity of some forms of cancer chemotherapy. The preclinical development of 2-aryl-1H-benzimidazole-4-carboxamides as resistance-modifying agents in cancer chemotherapy is described. 1H-Benzimidazole-4-carboxamides, particularly 2-aryl derivatives, are identified as a class of potent PARP inhibitors. Derivatives of 2-phenyl-1H-benzimidazole-4-carboxamide (23, K(i) = 15 nM), in which the phenyl ring contains substituents, have been synthesized. Many of these derivatives exhibit K(i) values for PARP inhibition 10 nM, with 2-(4-hydroxymethylphenyl)-1H-benzimidazole-4-carboxamide (78, K(i) = 1.6 nM) being one of the most potent. Insight into structure-activity relationships (SAR) for 2-aryl-1H-benzimidazole-4-carboxamides has been enhanced by studying the complex formed between 2-(3-methoxyphenyl)-1H-benzimidazole-4-carboxamide (44, K(i) = 6 nM) and the catalytic domain of chicken PARP. Important hydrogen-bonding and hydrophobic interactions with the protein have been identified for this inhibitor. 2-(4-Hydroxyphenyl)-1H-benzimidazole-4-carboxamide (45, K(i) = 6 nM) potentiates the cytotoxicity of both temozolomide and topotecan against A2780 cells in vitro (by 2.8- and 2.9-fold, respectively).
Potential Antitumor Agents. 59. Structure-Activity Relationships for 2-Phenylbenzimidazole-4-carboxamides, a New Class of "Minimal" DNA-Intercalating Agents Which May Not Act via Topoisomerase II
Denny, William A.,Rewcastle, Gordon W.,Baguley, Bruce C.
, p. 814 - 819 (2007/10/02)
A series of substituted 2-phenylbenzimidazole-4-carboxamides has been synthesized and evaluated for in vitro and in vivo antitumor activity.These compounds represent the logical conclusion to our search for "minimal" DNA-intercalating agents with the lowest possible DNA-binding constants.Such "2-1" tricyclic chromophores, of lower aromaticity than the structurally similar 2-phenylquinolines, have the lowest DNA binding affinity yet seen in the broad series of tricyclic carboxamide intercalating agents.Despite very low in vitro cytotoxicities, several of the compoundshad moderate levels of in vivo antileukemic effects.However, the most interesting aspect of their biological activity was the lack of cross-resistance shown to an amsacrine-resistant P388 cell line, suggesting that these compounds may not express their cytotoxicity via interaction with topoisomerase II.
