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Four new dammarane triterpenoid saponins cypaliurusides Z1–Z4 (1–4) and eight known analogs (5–12) were isolated from the leaves of Cyclocarya paliurus. The structures of the isolated compounds were determined using a comprehensive analysis of 1D and 2D NMR and HRESIMS data. The docking study demonstrated that compound 10 strongly bonded with PTP1B (a potential drug target for the treatment of type-II diabetes and obesity), hydrogen bonds, and hydrophobic interactions, verifying the importance of sugar unit. The effects of the isolates on insulin-stimulated glucose uptake in 3T3-L1 adipocytes were evaluated and three dammarane triterpenoid saponins (6, 7 and 10) were found to enhance insulin-stimulated glucose uptake in 3T3-L1 adipocytes. Furthermore, compounds 6, 7, and 10 exhibited potent abilities to promote insulin-stimulated glucose uptake in 3T3-L1 adipocytes in a dose-dependent manner. Thus, the abundant dammarane triterpenoid saponins from C. paliurus leaves exhibited stimulatory effects on glucose uptake with application potential as a antidiabetic treatment. [ABSTRACT FROM AUTHOR]

Two new coumarins 7-O-(6-O-(5-O-3,4,5-tri-methoxycinnamate-β-d-apiofuranosyl-β-d-glucopyranosyl)-6-methoxy coumarin (1) and 7-O-(6-O-(4-(2-hydroxy-1-hydroxymethyl-ethoxy)-3-methoxy-cinnamyl)-β-d-glucopyranosyl)-6-methoxy coumarin (2), along with 10 known metabolites, were isolated from the bark ofStreblus indicus, their structures were identified by comparison of experimental and published spectroscopic data. (S)-marmesinin (6) and scoparone (7) exhibited moderate antimicrobial activityin vitroagainstStaphylococcus aureusstrain with the MIC values of 62.5 and 125.0 μg/mL, respectively. Betulinic acid showed inhibitory activityin vitroagainst MCF-7 cell with IC50value of 9.5 ± 0.1 μM. [ABSTRACT FROM PUBLISHER]

RATIONALE: An unambiguous identification of compounds can be achieved by comparison of known fragmentation patterns. While the literature about fragmentation mechanisms of lignans, flavonoids and triterpenoids is few. So the present study analyses the fragmentation mechanisms of these compounds isolated from Streblus asper. METHODS: Electrospray ionization ion trap mass spectrometry (ESI-ITMS) and atmospheric pressure chemical ionization ion trap mass spectrometry (APCI-ITMS) were used to obtain the MSn spectra of the compounds. By analyzing the differences between the ions, the fragmentation mechanisms of these compounds were explored. RESULTS: Of the 29 compounds detected, 17, 7, and 5 were lignans, flavonoids and triterpenoids, respectively. The majority of lignans were found to give [M - H]- ions of sufficient abundance for MSn analyses. The flavonoids were prone to the loss of CO and H2O. The triterpenoids always lost one formic acid molecule and two hydrogens, or one H2O from [M - H]- to form the most abundant product ion in the MSn spectrum. CONCLUSIONS: ESI/APCI-ITMS were demonstrated to be fast, effective and practical tools to characterize the structures of flavonoids, triterpenoids and lignans. Results of the present study can help identify the analogous constituents by analyzing their MSn spectra. [ABSTRACT FROM AUTHOR]

A new chromone, 7-hydroxy-2-hydroxymethyl-8-methoxy-4-oxo-4H-chromene-6-carboxylic acid, named melachromone, along with 13 known compounds (2–14), including chromones, flavonoids, coumarins and phenylpropane derivatives, were isolated from the twig of Mallotus apelta. Their chemical structures were elucidated by using various spectroscopic methods. Anti-tumour evaluation of the compounds suggested that compound 1 exhibited medium cytotoxic activity against KB and HeLa Cells, with IC50 values of 9.50 and 9.23 μg mL− 1, respectively. [ABSTRACT FROM AUTHOR]