Three new matrine-type alkaloids from Sophora alopecuroides with cytotoxic activity

Three previously undescribed matrine-type alkaloids, sophaloseedlines U–W ( 1–3 ), together with three known analogues, were isolated from the seeds of Sophora alopecuroides L. Their chemical structures, including absolute configurations, were elucidated by comprehensive spectroscopic analyses (HR-ESI-MS, 1D and 2D NMR) and electronic circular dichroism (ECD) calculations. All compounds were evaluated for cytotoxic activities against two human breast cancer cell lines, MCF-7 and MDA-MB-231. Compound 4 exhibited the most potent activity, with IC₅₀ values of 24.8 μM and 26.1 μM, respectively. Three new matrine-type alkaloids were isolated from the seeds of Sophora alopecuroides L. Compound 4 exhibited cytotoxicity against MCF-7 and MDA-MB-231 breast cancer cell lines. • Three new matrine-type alkaloids, sophaloseedlines U–W, together with three known analogues were isolated from Sophora alopecuroides L. • Structures including absolute configurations were elucidated by HR-ESI-MS, 1D/ 2 D NMR, and ECD calculations. • Compound 4 exhibited the cytotoxicity against MCF-7 and MDA-MB-231 cells with IC₅₀ of 24.8 μM and 26.1 μM.