RESUMO
Four new norterpene cyclic peroxides (1-4), together with three known norterpene cyclic peroxides were isolated from the Xisha Islands Sponge Diacarnus megaspinorhabdosa. Their structures were elucidated on the basis of spectroscopic analyses and comparison with the related model compounds. The compounds (1-7) were evaluated for the inhibitory activity against the malaria parasite Plasmodium falciparum, all of them showed significant antimalarial activity with IC50 values in the range of 1.6-8.6 µM.
Assuntos
Antimaláricos/farmacologia , Peróxidos/farmacologia , Plasmodium falciparum/efeitos dos fármacos , Poríferos/química , Animais , Antimaláricos/síntese química , Antimaláricos/química , Antimaláricos/isolamento & purificação , Relação Dose-Resposta a Droga , Estrutura Molecular , Testes de Sensibilidade Parasitária , Peróxidos/síntese química , Peróxidos/química , Peróxidos/isolamento & purificação , Relação Estrutura-AtividadeRESUMO
Nine new aaptamine derivatives (1-9), together with three known related compounds (10-12), have been isolated from the South China Sea sponge Aaptos aaptos. The structures of all compounds were unambiguously elucidated on the basis of spectroscopic analyses. Structurally, compound 1 possesses a piperidinyl group fused to a demethyl(oxy)aaptamine moiety, whereas compounds 3-6 share an imidazole-fused 1H-benzo[de][1,6]naphthyridin-2(4H)-one skeleton. The cytotoxic activities of the compounds were evaluated against various human cancer cell lines, and compounds 2, 8, 11, and 12 showed potent cytotoxicities against HL60, K562, MCF-7, KB, HepG2, and HT-29 cells, with IC50 values in the range of 0.03 to 8.5 µM.
Assuntos
Antineoplásicos/isolamento & purificação , Antineoplásicos/farmacologia , Naftiridinas/isolamento & purificação , Naftiridinas/farmacologia , Poríferos/química , Animais , Antineoplásicos/química , China , Ensaios de Seleção de Medicamentos Antitumorais , Células HL-60 , Células HT29 , Humanos , Concentração Inibidora 50 , Células K562 , Estrutura Molecular , Naftiridinas/química , Ressonância Magnética Nuclear Biomolecular , Oceanos e MaresRESUMO
BACKGROUND: Peroxisome proliferator-activated receptors (PPARs) belong to the nuclear receptors superfamily and are transcription factors activated by specific ligands. Liver X receptors (LXR) belong to the nuclear hormone receptors and have been shown to play an important role in cholesterol homeostasis. From the previous screening of several medicinal plants for potential partial PPARγ agonists, the extracts of Cornus alternifolia were found to exhibit promising bioactivity. In this paper, we report the isolation and structural elucidation of four new compounds and their potential as ligands for PPAR. METHODS: The new compounds were extracted from the leaves of C. alternifolia and fractionated by high-performance liquid chromatography. Their structures were elucidated on the basis of spectroscopic evidence and analysis of their hydrolysis products. RESULTS: Three new iridoid glycosides including an iridolactone, alternosides A-C (1-3), a new megastigmane glycoside, cornalternoside (4) and 10 known compounds, were obtained from the leaves of C. alternifolia. Kaempferol-3-O-ß-glucopyranoside (5) exhibited potent agonistic activities for PPARα, PPARγ and LXR with EC50 values of 0.62, 3.0 and 1.8 µM, respectively. CONCLUSIONS: We isolated four new and ten known compounds from C. alternifolia, and one known compound showed agonistic activities for PPARα, PPARγ and LXR. GENERAL SIGNIFICANCE: Compound 1 is the first example of a naturally occurring iridoid glycoside containing a ß-glucopyranoside moiety at C-6.
