RESUMEN
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).
Asunto(s)
Apocynaceae/química , Extractos Vegetales/química , Alcaloides de Triptamina Secologanina/aislamiento & purificación , China , Cromatografía Líquida de Alta Presión , Espectroscopía de Resonancia Magnética , Rotación Óptica , Extractos Vegetales/aislamiento & purificación , Tallos de la Planta/química , Alcaloides de Triptamina Secologanina/química , Espectrofotometría InfrarrojaRESUMEN
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.