Novel indole-based scaffolds: Design, synthesis, molecular modeling, and anti-proliferative evaluation

Two novel series of indole-based scaffolds have been designed, synthesized, and screened for their anti-proliferative activities on the NCI-60 cell line panel. The novel structures of the indole-sulfonate and indole-aspirin mimic conjugates were designed as cyclin-dependent kinase 2 (CDK-2) inhibitors. The design approach depends on molecular hybridization between the indole scaffold and alkanesulfonates or with aspirin mimic analogs. The synthesized compounds were screened for their cytotoxic activity at a concentration of 10 µM. Compound 8a exhibited the most potent anticancer activity among the tested series and was further selected for the five-dose stage. At sub-micromolar doses, compound 8a showed anti-cancer potency against a panel of 60 tumor cell lines, with log GI₅₀ values in the range from - 4.50 µM to -6.45 µM. With log GI₅₀ values of -6.45, -6.42, -6.31, -5.96, and - 5.87 µM, respectively, the most sensitive cell lines were leukemia (SR), melanoma (MDA-MB-435), CNS cancer (SNB-75), ovarian cancer (OVCAR-3), and non-small cell lung cancer (NCI-H522). All the compounds were tested in an insilico study, encompassing drug likeness and absorption, distribution, metabolism, and excretion (ADME) prediction. A molecular modelling simulation study of the promising compound 8a in CDK-2 revealed the potential in vitro CDK-2 inhibitory assay result. The results demonstrate that, upon optimization, these novel indole-sulfonates could potentially act as new anticancer drugs.