Records of Natural Products

A new 4-hydroxyisoflavan, named lyratin D (1), was isolated from the whole plant of Solanum lyratum Thunb. Its structure and absolute configuration were elucidated through comprehensive analysis of its HR-ESI-MS, 1D and 2D NMR, and circular dichroism spectroscopy data. Compound 1 was then assessed for its cytotoxic effects on RAW264.7 murine macrophage cells, and its antioxidant activity was evaluated through DPPH assay.

Artemisia monosperma is a plant with many traditional uses including some affecting smooth muscles. The A. momosperma essential oil (AMEO) prepared by hydrodistillation from fresh and dry aerial parts was compared qualitatively and quantitatively using GC/MS. The drying process affected the yield and composition of AMEO. The bronchodilator potential was explored using isolated guinea-pig trachea in ex-vivo organ bath setup. In the tracheal contractions induced by different spasmogens, AMEO was able to completely relax contractions induced by carbachol (CCh; 1 µM) and high K+ (80 mM) at closely related doses (p > 0.05) indicating a dual inhibition of phosphodiesterase enzyme (PDE) and voltage-mediated L-type Ca++ channels blocker (CCB) as papaverine. The current study provides scientific support to the medicinal use A. monosperma in respiratory disorders. 

Four new polyoxygenated cucurbitane triterpene glycosides named kedrojiftene A-D (4-7), were isolated via different chromatographic techniques along with three phenolic compounds (1-3) from the crude extract of Kedrostis gijef. The isolated compounds were elucidated based on 1D, 2D-NMR spectroscopic analyses, HRESIMS and comparison with the related metabolites in literature. In bioassay, the α-glucosidase inhibitory assay for the isolated compounds was carried out and compounds (1-3) showed significant inhibitory activities.

Two previously undescribed cationic indole alkaloids, named ophiorrhines L (1) and M (2), was isolated from the Ophiorrhiza japonica. The structures were elucidated based on spectroscopic data and quantum calculations as well as X-ray crystallographic analysis. Alkaloids 1 and 2 exhibited moderate inhibitory activities on XOD (Xanthine Oxidase) with IC50 values 42.5 and 22.6 µM, respectively.