Bis-(10-deoxydihydroartemisinin)-phloroglucinol (9), has been synthesized in a one-step reaction and has demonstrated strong inhibition to cancer cell proliferation and immunosuppressive activity. The structure modification of the compound reduced its cytotoxicity, and among the analogs, bis-(10-deoxydihydroartemisinin)-phloroglucinol phenyl decanoate (16) showed significant reduction of ear swelling in a mouse model for DNFB-induced delayed-type hypersensitivity without observable toxicity in a dose-dependent manner.
View Article and Find Full Text PDFBackground: A novel artemisinin derivative, dihydroartemisinin-ursodeoxycholic acid conjugate (4), was found to exhibit strong immunosuppressive activity. Various methods were used to evaluate the immunosuppressive activity and mechanism of action of the compound to explore its potential applications.
Methods: T cell proliferation, mixed lymphocyte reaction (MLR), and Th1/Th17 differentiation assays were used to evaluate the immunosuppressive activity of the compound.
A series of dihydroartemisinin derivatives was synthesized, and their anti-proliferation activity against cancer cells was evaluated. Structure-activity relationship studies led to the discovery of dihydroartemisinin-bile acid conjugates that exhibit broad-spectrum anti-proliferation activities. Among them, the dihydroartemisinin-ursodeoxycholic acid conjugate (49) was the most potent, with IC values between 0.
View Article and Find Full Text PDFFour new aminothiazole-oximepiperidone cephalosporins (10a-10d) were synthesized, with their in vitro antibacterial activities against hospital isolated Gram-negative bacteria assessed. The results showed that compounds 10a-10d effectively inhibit a variety of Gram-negative bacteria. Compound 10a was the most potent compound, with comparable activity as ceftazidime.
View Article and Find Full Text PDFEight new dihydroartemisinin-O-glycosides were synthesized with their relative configurations were determined based on NMR spectrum. In vitro immunosuppressive assay showed that 10α-dihydroartemisinin-β-O-d-mannoside (19a) demonstrate 88% inhibition towards T cells proliferation and 98% reduction in IFN-γ levels in cell media. These results suggest that dihydroartemisinin-O-glycoside as a potential lead for further in vivo evaluation.
View Article and Find Full Text PDFFour new flavonoids were isolated from Campylotropis hirtella and these are a chromone and a 2H-chromene, an isoflavone and an isoflavanonol. The structures of these compounds were elucidated by extensive spectroscopic measurements. All of the compounds were assessed for immunosuppressive activity.
View Article and Find Full Text PDFAim: Deaggregators (deAgrs) are nontoxic organic molecules that possess the ability to deaggregate simple aggregates formed by hydrophobic lipophilic interactions (HLI). Since HLI-driven organic molecule aggregates may induce leukocyte adhesion, we investigated the influence of deAgrs on TNF-α-mediated leukocyte adhesion in vitro.
Methods: For adhesion studies, vascular endothelial cells or smooth muscle cells monolayers were treated with TNF-α (10 μg/L) and deAgrs for 24 h, followed by addition of monocytes or neutrophils suspension.
In an effort to identify natural compounds with immunosuppressive activity, nine new flavonoids, including one isoflav-3-ene derivative (1), one coumaronochromone (2), two isoflavanones (3, 4), one isoflavone derivative (6), one isoflavone (7), three flavonols (8, 9, 10), as well as one known compound, hydroisoflavone C (5), were isolated from the roots of Campylotropis hirtella. The structures of these compounds were elucidated by extensive spectroscopic measurements. All of the compounds were assessed for immunosuppressive activity.
View Article and Find Full Text PDFA new Pd-catalyzed cyanation reaction has been discovered using ethyl cyanoacetate as the cyanating reagent. A variety of electron-rich and electron-deficient aryl halides were efficiently converted into their corresponding nitriles in good to excellent yields.
View Article and Find Full Text PDFA convenient and efficient one-pot synthesis of cyclopamine from peimisine is described. The key steps involve one-pot hydrazination and subsequent Bamford-Stevens reaction. The mild reaction conditions, high overall yield as well as an easy purification indicate this process can potentially be used for the scale-up preparation of cyclopamine.
View Article and Find Full Text PDFEight new flavonoids, including three pterocarpene derivatives, hirtellanines C-E, two flavanones, hirtellanines F and G, three isoflavanones, hirtellanines H-J, as well as four known compounds were isolated from the roots of Campylotropis hirtella. The structures of the new compounds were elucidated by spectroscopic analyses, including 2D-NMR techniques. Pharmacological investigation indicated that the new compounds, particularly hirtellanines D and G, possessed potent immunosuppressive activities and low relative cytotoxicities.
View Article and Find Full Text PDFA method of reversed-phase high performance liquid chromatography (RP-HPLC) using diode array detection (DAD) was developed for the quantitative determination of 3'-geranyl-5,7,4'-trihydroxyisoflavone (compound 1) and 8,9-dihydroxy-1-methoxy-[6',6'-dimethylpyrano(2',3': 2,3)]pterocarpene (compound 2) in Campylotropis hirtella. The separation and quantification were achieved using an Agilent Zorbax SB-C18 column (250 mm x 4.6 mm, 5 microm), and mobile phases of acetonitrile and 0.
View Article and Find Full Text PDFFrom the dried roots of Campylotropis hirtella (Franch.) Schindl., five novel isoflavonoids, 3( S)-7,2',4'-trihydroxy-5,5'-dimethoxy-6-(3-methylbut-2-enyl)-isoflavan ( 1), 3( S)-2',4'-dihydroxy-5,5'-dimethoxy-(6'',6''-dimethylpyrano)-(2'',3'':7,6)-isoflavan ( 2), 3( R)-5,4'-dihydroxy-2'-methoxy-3'-(3-methylbut-2-enyl)-(6'',6''-dimethylpyrano)-(7,6 : 2'',3'')-isoflavanone ( 3), 3( R)-5,4'-dihydroxy-2'-methoxy-(6'',6''-dimethylpyrano)-(7,6: 2'',3'')-isoflavanone ( 4), and 3( R)-5,4'-dihydroxy-7,2'-dimethoxy-6-geranylisoflavanone ( 5) were isolated.
View Article and Find Full Text PDFIn an effort to identify new immunosuppressive agents from natural sources, 12 new geranylated flavonoids, 5,7,4'-trihydroxy-3'-[7-hydroxy-3,7-dimethyl-2(E)-octenyl]isoflavone (1), a racemate of 5,7,2',4'-tetrahydroxy-3'-[7-hydroxy-3,7-dimethyl-2(E)-octenyl]isoflavanone (2), 2''(S)-5,7-dihydroxy-[2''-methyl-2''-(4-methyl-3-pentenyl)pyrano]-5'',6'':3',4'-isoflavone (3), (2''S,3''R,4''S)-5,7,3'',4''-tetrahydroxy[2''-methyl-2''-(4-methyl-3-pentenyl)pyrano]-5'',6'':3',4'-isoflavone (4), a racemate of 3'-geranyl-5,7,2',4'-tetrahydroxyisoflavanone (5), a racemate of 3'-geranyl-4'-methoxy-5,7,2'-trihydroxyisoflavanone (6), 3'-geranyl-5,7,4',5'-tetrahydroxyisoflavone (8), 3'-geranyl-5,7,2',5'-tetrahydroxyisoflavone (9), 3'-geranyl-4'-methoxy-5,7,2'-trihydroxyisoflavone (10), 2(R),3(R)-3'-geranyl-2,3-trans-5,7,4'-trihydroxyflavonol (12), (2R,3R)-6-methyl-3'-geranyl-2,3-trans-5,7,4'-trihydroxyflavonol (13), and 5,7-dihydroxy-4'-O-geranylisoflavone (14), were isolated from the roots of Campylotropis hirtella (Franch.) Schindl. together with three previously described flavonoids.
View Article and Find Full Text PDFA method of reversed-phase high performance liquid chromatography (HPLC) coupled with evaporative light scattering detection (ELSD) was developed for the determination of jervine and veratramine in veratrum plants. The extraction method of total active alkaloids from the raw material was also established. The separation and quantification were achieved using a Kromasil C8column (250 mm x 4.
View Article and Find Full Text PDFThe aim of this study was to look for the chemical constituents of the bulbs of Fritillaria anhuiensis S. C. Chen et S.
View Article and Find Full Text PDFThe phenol gemini compounds were synthesized by rebuilding the substituents and lateral chain on the phenyl ring. Two parts of the molecules were connected by a spacer of hydrocarbon chain via ester groups. The deaggregation behaviors of target molecules were investigated by studying coaggregation behaviors, evaluating the deaggregating abilities in terms of fluorescence measurements, the measurements of their aggregation number and the effects on restraining the cell adhesion.
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