Synthesis of new arylisoxazole–oxindole conjugates as potent antiproliferative agents

A new series of arylisoxazole–oxindole derivatives (6a–r) were synthesized and evaluated for their antiproliferative activity against human cancer cell lines including non-small cell lung (A549), cervical (HeLa), breast (MCF-7), and prostate (DU-145) cancer cell lines. The synthesized compounds (6a–r) demonstrated excellent to moderate cytotoxicity with IC₅₀ values ranging from 0.82 to 3.69 μm. Some new compounds (6m–r) exhibited profound cytotoxicity better or similar to positive control. More particularly, the compound 6q possesses donating substituent like methoxy group presented at 5-position on D ring exhibited remarkable antiproliferative activity against A-549 (lung cancer) with an IC₅₀ value 0.82 μm. Further studies to determine the mechanistic aspects of these conjugates are under progress.