Design, synthesis, and biological evaluation of benzofuran- and 2,3-dihydrobenzofuran-2-carboxylic acid N-(substituted)phenylamide derivatives as anticancer agents and inhibitors of NF-κB.

With the aim of developing novel scaffolds as anticancer agents and inhibitors of NF-κB activity, 60 novel benzofuran- and 2,3-dihydrobenzofuran-2-carboxylic acid N-(substituted)phenylamide derivatives (1a-s, 2a-k, 3a-s, and 4a-k) were designed and synthesized from the reference lead compound KL-1156, which is an inhibitor of NF-κB translocation to the nucleus in LPS-stimulated RAW 264.7 macrophage cells. The novel benzofuran- and 2,3-dihydrobenzofuran-2-carboxamide derivatives exhibited potent cytotoxic activities (measured by the sulforhodamine B assay) at low micromolar concentrations against six human cancer cell lines: ACHN (renal), HCT15 (colon), MM231 (breast), NUGC-3 (gastric), NCI-H23 (lung), and PC-3 (prostate). In addition, these compounds also inhibited LPS-induced NF-κB transcriptional activity. The +M effect and hydrophobic groups on the N-phenyl ring potentiated the anticancer activity and NF-κB inhibitory activity, respectively. However, according to the results of structure-activity relationship studies, only benzofuran-2-carboxylic acid N-(4'-hydroxy)phenylamide (3m) was the lead scaffold with both an outstanding anticancer activity and NF-κB inhibitory activity. This novel lead scaffold may be helpful for investigation of new anticancer agents that act through inactivation of NF-κB.

Design and synthesis of 3,4-dihydro-2H-benzo[h]chromene derivatives as potential NF-κB inhibitors.

A novel class of NF-κB inhibitors were designed and synthesized based on KL-1156 (6-hydroxy-7-methoxychroman-2-carboxylic acid phenyl amide) which is unambiguously considered to be a promising inhibitor for the translocation step of NF-κB. Especially in this study we focused on the modifying the chroman moiety of KL-1156 into four parts for exploring the SAR studies linked with physical properties of substituents resulted the development of novel 1a-k, 2a-f, 3a-d and 4a-d derivatives of 3,4-dihydro-2H-benzo[h]chromene. From the SAR studies we were very delightfully identified that several new N-aryl-3,4-dihydro-2H-benzo[h]chromene-2-carboxamide derivatives (1a-k) exhibited good inhibitory activity and anti-proliferative activity than parent lead compound KL-1156, among them 1i exhibited outstanding inhibitory effect on LPS-induced NF-κB transcriptional activity and anti-proliferative activity on NCI-H23 lung cancer cell lines than KL-1156.