Development of metal-free one-pot sequential synthesis of carbazolyl-thiazolidinones as anti-leukemic agents with potential β-catenin/c-MYC pathway modulation: from synthesis to in vitro and in silico profiling.

Abstract

Cancer remains a leading cause of mortality worldwide, necessitating the development of new, selective, and potent therapeutic agents. In this study, a novel, metal-free, one-pot sequential synthetic approach was developed for the synthesis of carbazolyl-thiazolidinone (CTZD) derivatives via the reaction of N-octylcarbazole-3-carbaldehyde with variety of aromatic and aliphatic primary and secondary amines and thioglycolic acid. This strategy efficiently yielded a diverse range of CTZD derivatives (4a-p) in moderate to high yields (20-95%). The synthesized compounds were characterized by FTIR, NMR (1H, 13C, DEPT, APT), and HRMS. Their in vitro cytotoxicity was tested on human leukemia cell lines NB4, K562 and U937 using MTT assays, where four derivatives (4e, 4i, 4j, and 4o) exhibited potent, concentration-dependent antiproliferative activity over the tested concentration range (1.25-10 μM). As c-MYC is a key regulator of cell proliferation, qRT-PCR analysis demonstrated that these four derivatives significantly downregulated c-MYC mRNA expression, with compound 4j producing the greatest reduction, suggesting a potential association with modulation of the Wnt/β-catenin pathway. DNA fragmentation analysis showed no detectable late-stage apoptosis, indicating that the observed c-MYC downregulation and antiproliferative effects were not associated with late-stage apoptotic cell death. The ADME/T analysis of all compounds showed favorable pharmacokinetic profiles with prediction of good oral absorption (HIA >92%) and no hERG I liability. Molecular docking studies demonstrated strong binding affinities of these compounds to β-catenin protein (PDB ID: 7ZRB) with compound 4i showing strongest affinity with ΔG = -8.10 kcal/mol via H-bonds with Ser473, Asn430, Arg469 and His470 amino acid residues. The developed metal-free synthesis provided a sustainable route to bioactive carbazolyl-thiazolidinones, and derivatives 4e, 4i, 4j, 4o could be promising leads for targeting Wnt/β-catenin/c-MYC signaling in leukemia.