RESUMO
Melodicochinines A - D (1-4), four new monoterpene indole alkaloids (MIAs), along with 21 known ones, were isolated from the stems and twigs of Melodinus cochinchinensis. Their structures were elucidated on the basis of extensive spectroscopic analysis. A ubiquitin-rhodamine 110 assay showed that 11-methyloxytabersonine had potential inhibitory effect against ubiquitin-specific protease 7 (USP7).
Assuntos
Apocynaceae/química , Extratos Vegetais/química , Alcaloides de Triptamina e Secologanina/isolamento & purificação , China , Cromatografia Líquida de Alta Pressão , Espectroscopia de Ressonância Magnética , Rotação Ocular , Extratos Vegetais/isolamento & purificação , Caules de Planta/química , Alcaloides de Triptamina e Secologanina/química , Espectrofotometria InfravermelhoRESUMO
Acmoxanthones A-E (1-5), five new lavandulylated xanthones, were isolated from the aerial parts of Hypericum acmosepalum, together with four known xanthones. Their structures with absolute configurations were elucidated on the basis of analysis of MS, NMR and chiroptical properties. A bioassay against high glucose-induced damage on human umbilical vein endothelial cells (HUVECs) showed ananixanthone (6) and osajaxanthone (7) had potential antioxidative damage activity with EC50 values of 10.5 µg/mL and 7.6 µg/mL, respectively, while 3-hydroxy-2,4-dimethoxyxanthone (8) exhibited cytotoxic effect on the damaged cells with IC50 values of 7.1 µg/mL.
Assuntos
Hypericum/química , Xantonas/farmacologia , Antioxidantes/isolamento & purificação , Antioxidantes/farmacologia , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Humanos , Isoflavonas , Estrutura Molecular , Compostos Fitoquímicos/isolamento & purificação , Compostos Fitoquímicos/farmacologia , Componentes Aéreos da Planta/química , Xantonas/isolamento & purificaçãoRESUMO
Uralins A - D, four undescribed polycyclic polyprenylated acylphloroglucinols (PPAPs) featuring an unprecedented fused hexacyclic architecture, a unique monocyclic tetra-seco-tetranor-b-PPAP, an oxidative b-PPAP and a rare norspiroindane-type m-PPAP, respectively, were isolated from the aerial parts of Hypericum uralum, along with ten known PPAPs. Their structures and absolute configurations were elucidated by extensive spectroscopic techniques (MS, NMR, [α]D, CD), conceivable biogenetic pathways and time-dependent density functional theory-based electronic circular dichroism (TDDFT-ECD) calculations. Biological assays showed three b-PPAPs had moderate antioxidative damage activities, while spiroindanes exhibited moderate cytotoxic effects.