Synthesis of novel spiropyrazoline oxindoles and evaluation of cytotoxicity in cancer cell lines.

A series of novel spiropyrazoline oxindole derivatives was synthesized by 1,3-dipolar cycloaddition reaction. The compounds were screened for their in vitro cytotoxic activity against MCF-7 breast cancer cell line (estrogen receptor positive (ER+) and human epidermal growth factor receptor 2 negative (HER2-)). Of the nineteen spiropyrazoline oxindoles tested, six compounds have a GI50 below 12 μM The most potent compounds in this series were also evaluated against MDA-MB-231 breast cancer cell line (ER- and HER2-). Two spiropyrazoline oxindoles were highly selective between MCF-7 tumor cells and MDA-MB-231 tumor cells. More importantly, they were noncytotoxic against HEK 293T non tumor derived cell lines.