Triterpenoid saponins from Calliandra calothyrsus Meisn. and their antiproliferative activity against two digestive carcinoma human cell lines.

The chemical investigation of the flowers and twigs of Calliandra calothyrsus (Fabaceae) led to the isolation of three new oleanane-type triterpenoid saponins, named calothyrsusosides AC (13). Their structures were established by direct interpretation of their spectral data, mainly HRESIMS, 1D NMR and 2D NMR ( ¹ H, ¹ H NMR DOSY, ¹³ C NMR, COSY, HSQC, HMBC, HSQC-TOCSY and NOESY) and by comparison with literature data. Compounds 1 and 2 were tested for their antiproliferative activity against two digestive carcinoma human cell lines: Hep3B (hepatocellular carcinoma) and Caco-2 (epithelial colorectal adenocarcinoma). Both compounds exhibited an antiproliferative activity against the Hep3B cell line, with IC ₅₀ values of 6.0 and 6.5 μM, respectively, while no effect was detected against the epithelial colorectal adenocarcinoma Caco-2 (CC ₅₀  > 25 μM).
Competing Interests: Declaration of Competing Interest The authors declare that there is no conflicting interest.
(Copyright © 2020. Published by Elsevier B.V.)