Antimalarial and cytotoxic activities of pregnene-type steroidal alkaloids from Holarrhena pubescens roots

Authors

Sarot Cheenpracha, University of Phayao
Pannakorn Boapun, University of Phayao
Thunwadee Limtharakul, Chiang Mai University
Surat Laphookhieo, Mae Fah Luang UniversityFollow
Stephen G. Pyne, University of WollongongFollow

RIS ID

117692

Publication Details

Cheenpracha, S., Boapun, P., Limtharakul, T., Laphookhieo, S. & Pyne, S. G. (2019). Antimalarial and cytotoxic activities of pregnene-type steroidal alkaloids from Holarrhena pubescens roots. Natural Product Research, 33 (6), 782-788.

Abstract

The phytochemical investigation of an alkaloidal extract of Holarrhena pubescens roots led to the isolation and identification of a new pregnene-type alkaloid, mokluangin D (1), together with nine known steroidal alkaloids (2-10). The structure of the new metabolite was determined on the basis of spectroscopic analyses including 1D- and 2D-NMR spectroscopy and mass spectrometry. Compounds 3 and 4 showed potent antimalarial activity against Plasmodium falciparum K1 stain with IC₅₀ values of 1.2 and 2.0 μM, respectively, and showed weak cytotoxic activity against the NCI-H187 cell line with IC₅₀ values of 27.7 and 30.6 μM, respectively. The substituent groups at C-3 and the carbonyl group at C-18 are important for the activity against the P. falciparum K1 stain.