%0 Generic
%A Lim, Kuan-Hon
%A Raja, Vijay
J.
%A Bradshaw, Tracey
D.
%A Lim, Siew-Huah
%A Low, Yun-Yee
%A Kam, Toh-Seok
%D 2015
%T Ibogan, Tacaman, and Cytotoxic Bisindole Alkaloids
from Tabernaemontana. Cononusine, an Iboga Alkaloid
with Unusual Incorporation of a Pyrrolidone Moiety
%U https://acs.figshare.com/articles/dataset/Ibogan_Tacaman_and_Cytotoxic_Bisindole_Alkaloids_from_i_Tabernaemontana_i_Cononusine_an_Iboga_Alkaloid_with_Unusual_Incorporation_of_a_Pyrrolidone_Moiety/2164762
%R 10.1021/acs.jnatprod.5b00117.s002
%2 https://acs.figshare.com/ndownloader/files/3798661
%K Cell cycle
%K MS analyses
%K HT
%K Compounds 7
%K ervatensine
%K Unusual Incorporation
%K HCT
%K KB cells
%K Iboga Alkaloid
%K MDA
%K compounds 7
%K Pyrrolidone MoietySix
%K multidrug resistance
%K NMR
%K Cytotoxic Bisindole Alkaloids
%K IC 50
%K bisindole
%K indole alkaloids
%K Malayan Tabernaemontana corymbosa
%K 2 μ M
%K cell death
%K MCF
%X Six new indole alkaloids, viz., cononusine
(1, a rare
example of an iboga–pyrrolidone conjugate), ervaluteine (2), vincamajicine (3), tacamonidine (4), 6-oxoibogaine (5), and N4-chloromethylnorfluorocurarine chloride (6), and two
new vobasinyl-iboga bisindole alkaloids, ervatensines A (7) and B (8), in addition to other known alkaloids, were
isolated from the stem-bark extract of the Malayan Tabernaemontana
corymbosa. The structures of these alkaloids were established
on the basis of NMR and MS analyses and, in one instance (7), confirmed by X-ray diffraction analysis. Vincamajicine (3) showed appreciable activity in reversing multidrug resistance
in vincristine-resistant KB cells (IC50 2.62 μM),
while ervatensines A (7) and B (8) and two
other known bisindoles displayed pronounced in vitro growth inhibitory
activity against human KB cells (IC50 < 2 μM).
Compounds 7 and 8 also showed good growth
inhibitory activity against A549, MCF-7, MDA-468, HCT-116, and HT-29
cells (IC50 0.70–4.19 μM). Cell cycle and
annexin V-FITC apoptosis assays indicated that compounds 7 and 8 inhibited proliferation of HCT-116 and MDA-468
cells, evoking apoptotic and necrotic cell death.
%I ACS Publications