Publications by authors named "Shijin Qu"

Twelve monoterpene indole glycoalkaloids, comprising of three new ones, 19--rhynchophylloside A (), 7--rhynchophylloside A (), and 7--anthocephalusine A (), were isolated from the hook-bearing branches of . The structures and absolute configurations of were elucidated by analysis of MS, NMR, ECD, and single-crystal X-ray diffraction or TDDFT-ECD calculations. Glycoalkaloids and showed significant immunosuppressive activity against the proliferation of B lymphocyte induced by LPS with broad selective index.

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Article Synopsis
  • - Twelve compounds were identified from the leaves and twigs of a specific plant, including four new compounds: 6,7α-limondiol, ethyl 19-hydroxyisoobacunoate diosphenol, -benzoyl 3-prenyltyramine, and 9--methyl integrifoliodiol.
  • - The structures of these compounds were determined using mass spectrometry (MS), nuclear magnetic resonance (NMR), and single-crystal X-ray diffraction techniques.
  • - The compounds showed immunosuppressive effects, inhibiting the growth of T lymphocytes and B cells stimulated by ConA and LPS, respectively.
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Fraxinifolines A-F (1-6), six new B-seco limonoids, together with four known A,D-di-seco ones, were isolated from the twigs with leaves of Tetradium fraxinifolium. Their structures with absolute configurations were elucidated on the basis of analysis of MS, NMR, single-crystal X-ray diffraction and biogenetic pathway. An anti-inflammatory bioassay in vitro showed limonoids 1-3 had significant immunosuppressive effect against the production of pro-inflammatory cytokines (IL-1β and/or TNF-α) in lipopolysaccharide (LPS)-stimulated RAW264.

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"Land Use and Land Cover Change (LULCC)" is increasingly being affected by ecosystem services value. LULCC patterns have been subjected to significant changes over time, primarily due to an ever-increasing population. It is rare to attempt to analyze the influence of such changes on a large variety of ecosystem benefits in Madagascar island.

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Environmental managers have been striving to optimize landscape structure to achieve a sustained supply of ecosystem services (ESs). However, we still lack a full understanding of the relationships between landscape structure and ESs due to the absence of thorough investigations on the variability of these relationships in space and time. To fill this critical gap, we assessed landscape structure alongside four important ESs (agricultural production (AP), carbon sequestration (CS), soil conservation (SC), and water retention (WR)) in the Wuhan metropolitan area (WMA), and then analyzed the spatiotemporal impacts of landscape structure on ESs from 2000 to 2020 using Geographically and Temporally Weighted Regression.

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A better understanding of the dynamic variation in the ecosystem service value (ESV) under land use/cover change (LUCC) is conductive to improving ecosystem services and environmental protection. The present study took Landsat TM/ETM remote sensing images and socio-economic statistic data as data sources and extracted land-use data using RS and GIS technology at 5-year intervals from 1990 to 2020. Then, we interpreted the spatio-temporal characteristics of LUCC and analyzed ESV changes using the value equivalence method in the black soil region of northeastern China (BSRNC).

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Melodicochinines A - D (1-4), four new monoterpene indole alkaloids (MIAs), along with 21 known ones, were isolated from the stems and twigs of Melodinus cochinchinensis. Their structures were elucidated on the basis of extensive spectroscopic analysis. A ubiquitin-rhodamine 110 assay showed that 11-methyloxytabersonine had potential inhibitory effect against ubiquitin-specific protease 7 (USP7).

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Background: In the United States, distribution plans for the COVID-19 vaccination were established at the state level. However, some states, such as Connecticut, followed an age-based strategy without considering occupations or co-morbid conditions due to its simplicity in implementation. This strategy raised concerns about exacerbating health inequities because it did not prioritize vulnerable communities, specifically, minorities and low-income groups.

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Hookerianones A - E (1-5), five new polyprenylated acylphloroglucinols (PPAPs), along with six known ones, were isolated from the aerial parts of Hypericum hookerianum. Their structures were elucidated by analyses of MS, NMR, chiroptical properties, biogenetic pathway, and/or single crystal X-ray diffraction. A ubiquitin-rhodamine 110 assay showed that furohyperforin and hypercalin C, two representative PPAPs in this plant, inhibited more than 90% USP7 at the concentration of 10 μM.

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Article Synopsis
  • Researchers isolated five unique matrine-type alkaloids, named Alopecines A-E, from Sophora alopecuroides seeds, each featuring unusual chemical structures with dichlorocyclopropane or chloromethyl groups.
  • The structures of these alkaloids were determined using advanced techniques such as spectroscopy, X-ray diffraction, and computational methods.
  • Alkaloid 4 demonstrated strong inhibitory effects on the growth of specific immune cells, showing low effective concentration values (IC) of 3.98 μM for T lymphocytes and 3.74 μM for B cells.
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Twenty-one polycyclic polyprenylated acylphloroglucinols, including three new compounds named as hyperichoisins A (), B () and C (), were isolated from the aerial parts of . The structures of those new compounds were elucidated by analysis of mass, NMR data, and chiroptical properties. A bioassay showed that otogirinin B had significant inhibitory effect on cell proliferation of A549.

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Seventeen structurally diverse lignans, comprising six new compounds, ecdysanols A (1), B (11), C - E (13-15), and F (17), were isolated from the caulis of Urceola rosea. The structures and absolute configurations of these new compounds were elucidated by means of extensive analysis of mass and NMR data, as well as chiroptical properties. A bioassay in vitro showed that all lignans possessed anti-inflammatory effects by inhibiting the production of TNF-α, NO and/or IL-6 in LPS-stimulated RAW264.

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A phytochemical investigation on the twigs and leaves of Flueggea virosa (Euphorbiaceae) led to the isolation of flueggenoids A - E (1-5), five new 13-methyl-ent-podocarpanes, together with eleven known compounds (6-16). Their structures and absolute configurations were elucidated on the basis of extensive MS and NMR data analysis, and/or single-crystal X-ray diffraction, time-dependent density functional theory (TDDFT)-based electronic circular dichroism (ECD) calculations, and chemical transformation. All isolates were evaluated for anti-HCV activity, the results showed that terpenoids of F.

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The fruits of Swietenia macrophylla (skyfruits) are commercially used as healthcare products to improve blood circulation. An investigation of active ingredients of skyfruits led to the isolation of four new limonoids, swietemacrolides A-D (1-4), together with ten known limonoids (5-14) and one proto-limonoid (15). Their structures were elucidated on the basis of MS and NMR data analysis.

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Six triterpenoids (1-6), four megastigmanes (7-10) and five hydroxycinnamic acid derivatives (11-15) were isolated from the aerial part of Anisomeles indica (Lamiaceae). Of these components, compound 1 was identified to be a new triterpenoid with the structure of 2α,3α,19α-trihydroxyurs-12,20(30)-dien-28-oic acid based on extensive analysis of MS, 1D and 2D NMR spectroscopic data, while compounds 2-13 were obtained for the first time from Anisomeles species.

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A phytochemical investigation on the aerial part of Euphorbia helioscopia (Euphorbiaceae) led to the isolation of 22 highly oxygenated diterpenoids with structural types of ent-abietane, ent-kaurane, lathyrane, ent-atisane and ingenane. 17 of them, named euphelionolides A - N, 16-epi-18-hydroxy-abbeokutone, as well as eupheliotriols A and B, were identified to be previously undescribed compounds by extensive analysis of spectroscopic data. The stereostructures of euphelionolides A - K were determined by single crystal X-ray diffraction combined with analysis of substituent effects and comparison of optical characteristics.

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Background: Multi-drug resistance (MDR) remains a major impediment in cancer therapy. A major goal for scientists is to discover more effective compounds that are able to circumvent MDR and simultaneously have minimal adverse side effects.

Objective: In the present study, we aim to determine the anti-MDR effects of pyramidatine (Z88), a cinnamic acid-derived bisamide compound isolated from the leaves of Aglaia perviridis, on KB/VCR (vincristineresistant human oral cancer cells) and MCF-7/ADR (adriamycin-resistant human breast adenocarcinoma) cells.

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The first synthesis of dendroflorin has been achieved in 10 steps with an overall yield of 5.5%. The key step in the synthesis features the biphenyl structure is built through Suzuki-Miyaura reaction.

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Two new triterpenoids, termichebuloside A (1), an unusual dimeric triterpenoid saponin, and termichebulolide (2), an oleanolic acid-type lactone, along with 11 known triterpenoids, were isolated from MeOH extract of the barks of Terminalia chebula. The structures of 1 and 2 were elucidated to be arjunglucoside I-(3-O-19',23-O-19')-18,19-seco-19-hydroxyarjunglucoside I (1) and 2α,3β,23-trihydroxyolean-11,13(18)-dien-28,19β-olide (2), respectively, on the basis of spectroscopic evidences and biogenetic consideration.

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Aglinin A (1) is a mixture of C(24)-epimeric 20S,24-epoxy-24,25-dihydroxy-3,4-secodammar-4(28)-en-3-oic acid and present in plants of the family Meliaceae. The two epimers of 1 were resolved through an acetonide reaction, and the absolute configurations of two derivatives were deduced by the analysis of their (13)C NMR differences induced by γ-gauche or steric effect. Based on it, the (13)C NMR assignment of 24R-1 and 24S-1 was also established.

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Two new arylnaphthalene lignan glycosides, named reticulatusides A (1) and B (2), together with eight known compounds were isolated from the 95% EtOH extract of the whole plant of Phyllanthus reticulatus. The structures of the new compounds were elucidated by spectroscopic methods.

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Lamiolactone (1), a new iridoid lactone, together with five known iridoids, were isolated from the 95% EtOH extract of the roots of Lamiophlomis rotata. The structure of 1 was elucidated to be methyl antirrhinolide-4-carboxylate on the basis of spectroscopic analysis.

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A series of tryptamine derivatives were synthesized and evaluated for their anti-hepatitis B virus (HBV) activity and cytotoxicity in the HepG2.2.15 cell line.

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A new dammarane-type triterpenoid saponin, (20R)-ginsenoside ST(2) (1), along with five known saponins was isolated from the hongshen extract of Shenmai injection. The structure of 1 was elucidated to be (20R)-dammar-23(E)-ene-3β,6α,12β,20,25-pentol 6-O-β-D-glucopyranoside by means of spectroscopic methods.

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A new lycopodane-type Lycopodium alkaloid, 6α-hydroxy-5,15-oxide-lycopodane (1), and seven known alkaloids were isolated from the whole plants of Huperzia serrata. Their structures were elucidated by means of spectroscopic methods. 12-Deoxyhuperzine O (2) was reported as a naturally occurring alkaloid for the first time, and showed an antagonist effect on the N-methyl-d-aspartate receptor with an IC(50) value of 0.

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