Ibogan, tacaman, and cytotoxic bisindole alkaloids from tabernaemontana. Cononusine, an iboga alkaloid with unusual incorporation of a pyrrolidone moiety.
J Nat Prod
; 78(5): 1129-38, 2015 May 22.
Article
en En
| MEDLINE
| ID: mdl-25919190
ABSTRACT
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 N(4)-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.
Texto completo:
1
Colección:
01-internacional
Banco de datos:
MEDLINE
Asunto principal:
Pirrolidinonas
/
Tabernaemontana
/
Alcaloides Indólicos
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Indoles
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Antineoplásicos Fitogénicos
Límite:
Humans
País/Región como asunto:
Asia
Idioma:
En
Revista:
J Nat Prod
Año:
2015
Tipo del documento:
Article
País de afiliación:
Malasia