查看更多>>摘要：? 2021 Elsevier B.V.Three novel alkaloids, identified as (E)-N-((2R)-3-(2,5-dihydroxy-4-((3,4,5-trihydroxy-6-(hydroxymethyl)tetrahydro-2H-pyran-2-yl)oxy)phenyl)-2-hydroxypropanoyl)-3-(4-hydroxyphenyl)acrylamide (1), named oleracrylimide A, (E)-N-((2R)-3-(2,5-dihydroxy-4-((3,4,5-trihydroxy-6-(hydroxymethyl)tetrahydro-2H-pyran-2-yl)oxy)phenyl)-2-hydroxypropanoyl)-3-(4-hydroxy-3-methoxyphenyl)acrylamide (2), named oleracrylimide B, and (E)-N-((2R)-3-(2,5-dihydroxy-4-((3,4,5-trihydroxy-6-(((3,4,5-trihydroxy-6-(hydroxymethyl)tetrahydro-2H-pyran-2-yl)oxy)methyl)tetrahydro-2H-pyran-2-yl)oxy)phenyl)-2-hydroxypropanoyl)-3-(4-hydroxy-3-methoxyphenyl)acrylamide (3), named oleracrylimide C were isolated from Portulaca oleracea L. and the structures of the three novel compounds were determined by 1D and 2D NMR, circular dichroism, and UHPLC-ESI-QTOF/MS spectroscopic methods. Moreover, the bioactivities of anti-inflammation of the three compounds were investigated via testing RAW 264.7 macrophage cell stimulated by Lipopolysaccharide.
查看更多>>摘要：? 2021 Elsevier B.V.Ten undescribed cadinane-type sesquiterpenes (1?10) were isolated from the whole plant of Eupatorium chinense. Their planar structures were mainly elucidated by extensive analysis of spectroscopic data and DFT NMR calculations. The absolute configurations of 1, 2, and 3 were determined by TDDFT ECD calculations while those of compounds 4–7 and 9 were confirmed by single crystal X-ray diffraction experiments. Compounds 2 and 3 are a pair of C-10 epimers, compounds 4 and 5 a pair of C-1 epimers, and compounds 9 and 10 a pair of compounds isomerized at both C-1 and C-10. A possible biosynthetic pathway for these new sesquiterpenes was proposed.
查看更多>>摘要：? 2021 Elsevier B.V.Ruta graveolens L. has been widely used to treat various skin ailments, especially vitiligo. In this study, we isolated a new furanocoumarin named Rutagrarin (1) along with 14 known compounds (2–15) from the aerial parts of R. graveolens and elucidated their chemical structures via various spectroscopy. We found that compound 5 promoted melanogenesis and tyrosinase activity in B16 cells. Further investigation on underlying mechanisms revealed that compound 5 activated the transcription of microtia-related transcription factors and promoted the production of melanin in B16 cells via the Akt/GSK-3β/β-catenin pathway. Therefore, we confirmed the traditional efficacy of R. graveolens and speculated that compound 5 could be used as a natural drug to treat vitiligo.
查看更多>>摘要：? 2021 The AuthorsPseudostellaria heterophylla (Miq.) Pax. (Taizishen, TZS) contains a variety of natural active cyclic-peptide compounds (CP). In this article, four kinds of CP monomers were isolated by HPLC and the structures were identified by mass spectrometry. The in vivo absorption of CP was detected by UPLC-MS/MS. The interaction between CP and membrane receptor was analyzed by SPR. As a result, the relative absorption rate of CP was Pesudostellarin B > Heterophyllin B > Pesudostellarin C > Pesudostellarin E. The difference in absorption rate of CP in vivo was related to its interaction with membrane receptors. The absorption mechanism of CP might be different. This is the first report that in vivo absorption study of different CP from TZS and explore its absorption mechanism, laying a theoretical foundation for the research and development of its oral drugs, and providing new ideas for the study of the absorption mechanism of CP from traditional Chinese medicine.
查看更多>>摘要：? 2021 Elsevier B.V.Two unprecedented ent-18,19-dinoricetexane diterpenoid glycosides, named abieshanesides A (1) and B (2), together with seven known compounds, have been isolated from the dead trunks and branches of Abies beshanzuensis M.H. Wu. To our knowledge, abieshanesides A and B represent the first ent-18,19-dinoricetexane diterpenoid glycosides found in natural sources. Their structures and absolute configurations were elucidated by using a combination of spectroscopic techniques and comparison of experimental and calculated electronic circular dichroism (ECD) data. The MTT experiments showed that (E)-resveratrol (7) could inhibit viability of MH7A cells with the IC50 value of 12.5 μM. Compound 7 was able to block MH7A cell proliferation and was associated with G0/G1-phase cell cycle arrest. Flow cytometric analysis showed that the treatment by 7 significantly induced the proliferation of MH7A cells in a dose-dependent manner.
查看更多>>摘要：? 2021 Elsevier B.V.Marine-derived fungi can usually produce structurally novel and biologically potent metabolites. In this study, a new diketopiperazine alkaloid (1) and two new polyketides (10 and 11), along with 8 known diketopiperazine alkaloids (2–9) were isolated from marine-derived fungus Penicillium sp. TW58-16. Their structures were fully elucidated by analyzing UV, IR, HR-ESI-MS, 1D, and 2D NMR spectroscopic data. The absolute configurations of the new compounds 1, 10 and 11 were ascertained by X-ray diffraction (Cu Kα radiation) and comparing their CD data with those reported. In addition, the antibacterial activities of these compounds against Helicobacter pylori in vitro were assessed. Results showed that compounds 3, 6, 8 and 9 displayed moderate antibacterial activity against standard strains and drug-resistant clinical isolates of H. pylori in vitro. This result demonstrates that diketopiperazine alkaloids could be lead compounds to be explored for the treatment of H. pylori infection.
查看更多>>摘要：? 2021 Elsevier B.V.Kiwi (Actinidia chinensis) plants are severely destroyed by canker disease which is caused by the bacterium Pseudomonas syringae pv. actinidiae (Psa). This program tries to find anti-Psa agents among secondary metabolites of endophytic fungi from kiwi plant itself. The chemical investigation on one kiwi endophytic fungi, Fusarium tricinctum, resulted in the isolation of nine new imidazole alkaloids, fusaritricines A-I (1–9) together with seven known analogues (10–16). The structures of new compounds were established by extensive spectroscopic methods. Compounds 2, 3, 9, and 13 showed good antibacterial activity against Psa with MIC values between 25 and 50 μg/mL. It is suggested that imidazole alkaloids should be potential anti-Psa agents.
查看更多>>摘要：? 2021 Elsevier B.V.Five new sesquiterpenes, namely, guaianes A-E (1–5), including one novel carbon skeleton guaiane-type sesquiterpene derivatives (1), together with thirteen known compounds (6–18), were isolated from the aerial parts of Pogostemon cablin (Blanco.) Benth. Their chemical structures were mainly established through the relative spectroscopic data, while the absolute configurations of compounds 1–5 were elucidated on the base of single-crystal X-ray diffraction analysis and electronic circular dichroism (ECD) calculations. All compounds were tested for their inhibiting effects on NO production in LPS-stimulated BV2 microglia cells as well as the cell viabilities. The results showed that compounds 2–16 and 18 possessed moderately anti-inflammatory activities at a concentration of 50 μM.
查看更多>>摘要：? 2021Chemical fractionation of the EtOH extract of a medicinal macro fungus, Inonotus obliquus, afforded an array of lanostane-type triterpenoids (1?11) including two new ones (1 and 8). The structures of these compounds were determined on the basis of spectroscopic analyses, single crystal X-ray crystallography of 3–6 and biosynthetic considerations. With the confirmatory structural information provided by X-ray diffraction analysis in hand, several previously reported 21,24-cyclolanostanes, such as inonotsutriols A–C and (20R,21S,24S)-21,24-cyclopenta-3β,21,25-trihydroxylanosta-8-ene, were structurally corrected. In addition, the NMR data of other types of 21,24-cyclo triterpenoids were also re-examined and structural revisions were thus suggested. Compounds 2, 6 and 8 showed significant cytostatic effects against a panel of tumor cell lines with IC50 values ranging from 7.80 to 18.5 μM. Further assays established that compound 2 exerted promising in vitro anti-breast cancer potential by inhibiting the proliferation and migration of 4T1 cells.
查看更多>>摘要：? 2021 Elsevier B.V.Seven new terpenes and its derivatives classified into a p-menthane glycoside (1), a guaianolide glycoside (2), three eudesmane and its glycosides (3–5), and two mono-terpene derivatives (9 and 10) were isolated from Ainsliaea bonatii, together with three known guaianolides (6–8). Their structures were elucidated by spectroscopic data analysis, and absolute configurations were determined by DP4+ probability analysis via calculated 13C NMR data of isomers. Compounds 6 and 9 showed nitric oxide (NO) inhibitory effects in LPS-induced RAW 264.7 macrophage cells with IC50 values of 9.3 and 10.6 μM, respectively.
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