Antiproliferative piperidine alkaloids from giant taro (Alocasia macrorrhiza)

Giant taro (Alocasia macrorrhiza (L.) Schott), is a perennial ornamental plant. In this study, nine new (1-9) and six known (10-15) piperidine alkaloids were obtained from the rhizomes of A. macrorrhiza. The chemical structures and absolute configurations were established utilizing a variety of spectroscopic techniques, Mosher, Snatzke method and single-crystal X-ray crystallography. The isolates were evaluated for their antiproliferative activity on SGC-7901, MDA-MB-231, HepG2, K562, CNE2, SPC-A-1, HeLa, A-375 and Hacat cells. The results revealed that piperidine alkaloids exhibited significant antiproliferative activity against these tumor cells, with a particularly pronounced effect on K562 cells. [Display omitted] •Fifteen pyridine alkaloids have been isolated from Alocasia macrorrhiza, including nine new compounds.•Antiproliferative activities of the isolated alkaloids were investigated.•Most pyridine alkaloids exhibited potent antiproliferative activity against K562 cells.•Alocasia macrorrhiza may have potential for the treatment of tumor.