A series of N-substituted iminosugar C-glycosides were synthesized and tested for α-glucosidase inhibition. The results suggested that 6e is a promising and potent α-glucosidase inhibitor. Enzymatic kinetic assays indicated that compound 6e may be classified as an uncompetitive inhibitor. The study of structure-activity relationships of those iminosugars provided a starting point for the discovery of new α-glucosidase inhibitors.

Background Rhizoma paridis (RP) is a traditional Chinese herb used for the treatment of tumors, detoxification and hemostasia. Studies show the main components of RP are Polyphyllin I (PPI), polyphyllin VI (PPVI), and polyphyllin VII (PPVII). However, the pharmaco-mechanisms of these compounds are not clear. Objectives: By used ¹H nuclear magnetic resonance (¹H-NMR) based metabolomics approach to identify the Anticancer effects of PPI, PPVI and PPVII in HepG2 cells. Methods ¹H nuclear magnetic resonance (¹H-NMR) based metabolomics approach was applied to investigate the toxicological effect of PPI, PPVI, PPVII on HepG2 cells. Multivariate statistical analysis was employed to examine the metabolic changes and abnormal metabolic pathways, including Principal Component Analysis (PCA), Partial Least Squares Discriminant Analysis (PLS-DA), and orthogonal PLS-DA (OPLS-DA). Results The results showed that the effects of metabolic phenotypes were affected separately by PPI, PPVI, and PPVII. The metabolic phenotypes were also changed over time. The characteristic metabolites were varied by affecting different polyphylins, which were identified by the reconstructed OPLSDA loading plots. According to the characteristic metabolites, the mainly disturbed metabolic pathways were found, such as alanine, aspartate and glutamate metabolism, pyruvate metabolism, glycine, serine, and threonine metabolism. Conclusion The current work could allow us to understand the therapeutic effect of RP in metabolism. It also indicated that RP would be a promising candidate for liver cancer treatment.

The chemical investigation of the EtOAc extract of the fresh flowers of Juglans regia L. resulted in a new α-tetralonyl glucoside (1) and two known glucosides (2-3). The structure of the new compound was determined by extensive 1D and 2D NMR spectroscopic analysis and HRESIMS. The biological evaluation of the obtained glucosides showed that compound 1 and 3 displayed good antioxidant and antibacterial activities. These two compounds were identified as the main functional molecules in the fresh flowers of Juglans regia L.

Inhibition of glycoside hydrolases has widespread application in the treatment of diabetes. Based on our previous findings, a series of dihydrofuro[3,2-b]piperidine derivatives was designed and synthesized from D- and L-arabinose. Compounds 32 (IC₅₀ = 0.07 μM) and 28 (IC₅₀ = 0.5 μM) showed significantly stronger inhibitory potency against α-glucosidase than positive control acarbose. The study of the structure–activity relationship of these compounds provides a new clue for the development of new α-glucosidase inhibitors.

: A novel bis-indole alkaloid was isolated from the flowers of Rauvolfia Yunnanensis Tsiang. Its structure was elucidated as 10,11´- dimethoxy-11,10´-bis-[N(a)-methyl deacetyldeformyl- 1,2- dihydro akuammiline(2β)] (1) on the basis of spectroscopic analysis, including 1D and 2D NMR techniques as well as HRESI-MS and comparison with data from the literature. The bis-indole alkaloid displayed more potent antihypertension activity and much lower hepatotoxicity in vivo than Reserpine.