Two new triterpenoids, teuviscins A (1) and B (2), were isolated from the whole plants of Teucrium viscidum. Compound 1 possessed a rare 7(8→9)abeo-9R-D:C-friedo-B′:A′-neo-gammacerane skeleton, and compound 2 is a taraxerane triterpene acid. Their structures were characterized by extensive spectroscopic methods (HR-ESI-MS, 1D and 2D NMR), and the absolute configurations of 1 and 2 were secured by single-crystal X-ray diffraction analyses using Cu Kα radiation. Compound 2 showed anti-AD bioactivity which delayed animals paralysis of transgenic AD Caenorhabditis elegans.
The purpose of this study was to evaluate the effects of astragalin on the central nervous system. Astragalin is a monomeric compound found in the leaves of Eucommia ulmoides using a system solvent method. In the experiments, astragalin showed significant effects on mice, including reduced spontaneous activity, increased sleep ratio, shortened sleep latency and lengthened sleep time with a subthreshold or superthreshold dose of pentobarbital sodium. In addition, astragalin effectively reduced the convulsion rate and prolonged convulsion latency. These findings confirmed that astragalin had excellent sedative and hypnotic effects and has potential to be commercialised as a novel nutraceutical agent to promote calming and improve central nervous system-associated pathologies.
13 February 2018 in Organic & Biomolecular Chemistry
Norcrassin A (1), a novel C16 tetranorditerpenoid, featuring a new carbon skeleton, and bicrotonol A (2), an unusual dimeric labdane-type diterpenoid, were isolated from Croton crassifolius.