Design, synthesis, and in vitro and in vivo biological evaluation of 2-amino-naphtho[2,3-b]thiophene-4,9-dione derivatives as potent anticancer agents.

This study synthesized a series of substituted 2-amino-naphtho[2,3-b]thiophene 4,9-dione derivatives through multi-component reactions involving Domino and Krapcho strategies. Among the 15 synthesized analogs, compound 4a emerged as a lead compound with potent anticancer activity against the aggressive triple-negative breast cancer (TNBC) cell line MDA-MB-231. Mechanistic investigations demonstrated that treatment with compound 4a induced dose-dependent inhibition of cell viability, cell cycle arrest, and robust apoptotic responses in MDA-MB-231 cells. Apoptotic assays confirmed enhanced caspase-3/7 activation and increased reactive oxygen species (ROS) generation. Crucially, immunocytochemistry analysis revealed that compound 4a significantly suppressed the phosphorylation of Akt at Ser473, a pivotal regulatory event in the PI3K/Akt signaling pathway, which is frequently dysregulated in TNBC. This inhibition disrupted pro-survival signaling, sensitizing MDA-MB-231 cells to apoptosis while sparing normal cells, highlighting compound 4a as a potential anticancer agent through selective therapeutic targeting of Akt-driven pathways.