Regioselective synthesis of indole-thiazolidine-2,4-dione coupled isoxazoles as in vitro tubulin polymerization inhibitors

Herein we synthesized new indole-thiazolidine-2,4-dione coupled isoxazoles (7a-n) via simple reactions like Npropargylation, Knoevenagel condensation and copper (I) catalysed one pot regioselective reactions. All the newly synthesized compounds were characterized by 1H-NMR, 13C-NMR and Mass spectra and they were screened for in vitro anticancer activity against three human cancer cell lines like A549 (lung), MCF-7 (breast), and SKOV3 (ovarian) using MTT assay and etoposide was used as the standard drug. As per the results the compounds 7e, 7f and 7g where shown selectivity towards A549 cell line with IC50 values of 5.27 mu M, 3.14 mu M and 6.25 mu M respectively and they are high active than etoposide. Further in vitro tubulin polymerization assay on three potent compounds ( 7e, 7f and 7g) revealed that compounds 7e and 7f have exhibited potency than standard combretastatin A-4 with IC50 values 0.82 and.044 mu M respectively.