Synthesis, Biological Evaluation, and Autophagy Mechanism of 12<i>N</i>‑Substituted Sophoridinamines as Novel Anticancer Agents

A series of 12<i>N</i>-substituted sophoridinamine derivatives were synthesized and evaluated for their cytotoxic activities in human HepG2 hepatoma cells. Structure–activity relationship revealed that introduction of a suitable arylidene or arylethyl at the <i>N</i>′-end could greatly enhance antiproliferation potency. Among them, compound <b>6b</b> possessing a <i>N</i>′-trimethoxyphenyl methylene exhibited potent antiproliferation effect against three human tumor cell lines including HepG2, leukemia (K562), and breast cancer (HMLE), with IC₅₀ between 0.55 and 1.7 μM. The underlying mechanism of <b>6b</b> against tumor cells is to block autophagic flux, mainly through neutralizing lysosomal acidity. Our results indicated that compound <b>6b</b> is a potent lysosomal deacidification agent and is accordingly able to block autophagic flux and inhibit tumor cell growth

Synthesis and Biological Evaluation of Sophoridinol Derivatives as a Novel Family of Potential Anticancer Agents

New N-substituted sophoridinic acid/ester and sophoridinol derivatives were synthesized and evaluated for their cytotoxic activity in human HepG2 hepatoma cells from the lead sophoridine (1). Among the newly synthesized compounds, sophoridinol 7i displayed a potential antiproliferative activity with an IC50 of 3.1 μM. Importantly, it exerted an almost equipotent effect against both wild MCF-7 and adriamycin (AMD)-resistant MCF-7 (MCF-7/AMD) breast carcinoma cell lines. Its mode of action was to arrest the cell cycle at the G0/G1 phase, consistent with that of the parent 1. In addition, compound 7i also showed a reasonable ClogP value and favorable pharmacokinetic property with an area under the concentration–time curve (AUC) of 10.3 μM·h in rats, indicating an ideal druggable characteristic. We consider sophoridinol derivatives to be a novel family of promising antitumor agents with an advantage of inhibiting drug-resistant cancer cells