RESUMO
Four limonoids, triconoids A-C (1-3) possessing a new rearranged mexicanolide skeleton and triconoid D (4) furnishing a new rearranged 1,2-seco-phragmalin skeleton, were isolated from the Nepalese plant Trichilia connaroides. Two rearranged limonoid skeletons sharing an F ring of methyl 5-oxotetrahydrofuran-2-carboxylate were postulated to be formed biosynthetically via a very unique chemical cascade. Their structures were fully accomplished by spectroscopic data, single-crystal X-ray diffraction, and electrostatic circular dichroism analysis.
Assuntos
Limoninas/biossíntese , Meliaceae/metabolismo , Fenômenos Bioquímicos , Vias Biossintéticas , Limoninas/químicaRESUMO
Chemical investigation into the alkaloidal constituents of the Nepalese Daphniphyllum himalense has returned two new compounds, himalensines A (1) and B (2), with unprecedented carbon skeletons. Structures of the two alkaloids have been characterized on the basis of spectroscopic methods, especially via 2D NMR data analysis. Himalensine B (2) showed marginal inhibitory activities against two kinases, PTP1B and IKK-ß.
Assuntos
Alcaloides/isolamento & purificação , Piridinas/síntese química , Alcaloides/química , Aminas/química , Aurora Quinase A/antagonistas & inibidores , Cloretos/química , Ciclização , Medicamentos de Ervas Chinesas/química , Compostos Férricos/química , Desacetilase 6 de Histona , Histona Desacetilases/efeitos dos fármacos , Quinase I-kappa B/antagonistas & inibidores , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Folhas de Planta/química , Proteína Tirosina Fosfatase não Receptora Tipo 1/antagonistas & inibidores , Piridinas/química , Saxifragaceae/químicaRESUMO
The crude extracts of tubers of Aconitum spicatum (Bruhl) Stapf were investigated for in vitro antileishmanial activity against Leishmania major. The dichloromethane extract at pH 2.5 showed antileishmanial activity with IC50 value of 27.10 ± 0.0 µg/mL. Chromatographic purification of the dichloromethane extract led to isolation of three C-19 norditerpenoid alkaloids indaconitine (1), chasmaconitine (2) and ludaconitine (3). Compounds 3 and 2 showed antileishmanial activity with IC50 = 36.10 ± 3.4 and 56.30 ± 2.1 µg/mL, respectively. Compound 1 was less effective (IC50 > 100 µg/mL). The cytotoxicity of compounds 1, 2 and 3 studied against MCF7, HeLa and PC3 cancer cell lines and 3T3 normal fibroblast cell line did not show cytotoxicity at 30 µM.
RESUMO
Thirteen new hydroxylated calyciphylline A-type Daphniphyllum alkaloids (1-13) were isolated from an ethanolic extract of Daphniphyllum himalense. These structures were characterized on the basis of spectroscopic data analysis, especially from their 2D NMR spectra. Oxidation at the C-3, C-9, C-11, and C-12 positions is reported for the first time for this class of compounds. Selective compounds showed low inhibitory rates against three kinase enzymes, PTP1B, aurora A, and IKK-ß, at a concentration of 20 µg/mL.