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31.
Two new triterpenoid glycosides, 3α,19α,23α‐trihydroxy‐2‐oxo‐12‐ursen‐28‐Oβ‐d ‐glucopyranoside ( 1 ) and 3α,19α,23α‐trihydroxy‐2‐oxoolean‐12‐en‐28‐Oβ‐d ‐glucopyranoside ( 2 ) as well as three known compounds, 2α,3α,19α‐trihydroxyolean‐12‐en‐28‐Oβ‐d ‐glucopyranoside ( 3 ), 2α,3α,19α,23‐tetrahydroxy‐12‐ursen‐28‐Oβ‐d ‐glucopyranoside ( 4 ), and 2α,3β,19α,23‐tetrahydroxyurs‐12‐en‐28‐oic acid ( 5 ) were isolated from 75% EtOH extract of Rosa cymosa. Their structures were elucidated by extensive spectroscopic methods. All the isolated compounds displayed moderate inhibitory activity against LPS‐induced NO production in macrophages.  相似文献   
32.
Four new diketopiperazine alkaloids, rel‐(8R)‐9‐hydroxy‐8‐methoxy‐18‐epi‐fumitremorgin C ( 1 ), rel‐(8S)‐19,20‐dihydro‐9,20‐dihydroxy‐8‐methoxy‐9,18‐di‐epi‐fumitremorgin C ( 2 ), rel‐(8S,19S)‐19,20‐dihydro‐9,19,20‐trihydroxy‐8‐methoxy‐9‐epi‐fumitremorgin C ( 3 ), and (3S,8S,9S,18S)‐8,9‐dihydroxyspirotryprostatin A ( 4 ), together with the eight known compounds 5 – 12 , were isolated from the endophytic fungus Aspergillus fumigatus. The structures of the new compounds were determined by extensive spectroscopic methods including HR‐ESI‐MS, NMR, and CD experiments. Compound 12 showed weak inhibitory activity in vitro against the release of β‐glucuronidase in rat polymorphonuclear leukocytes induced by the platelet‐activating factor. None of the twelve compounds exhibited detectable cytotoxic activities toward five human tumor cell lines (HCT‐8, Bel‐7402, BGC‐823, A549, and A2780) in the MTT assay.  相似文献   
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34.
Diallyldimethylammonium chloride modified magnetic nanoparticles were synthesized by the “thiol‐ene” click chemistry reaction. Diallyldimethylammonium chloride rendered the material plenty of quaternary ammonium groups, and thus the excellent aqueous dispersibility and anion‐exchange capability. The novel material was then used as the magnetic solid‐phase extraction sorbent to extract eight non‐steroidal anti‐inflammatory drugs from water samples. Combined with high‐performance liquid chromatography and ultraviolet detection, under the optimal conditions, the developed method exhibited wide linearity ranges (1–1000, 2–1000, and 5–1000 ng/mL) with recoveries of 88.0–108.6% and low limits of detection (0.3–1.5 ng/mL). Acceptable precision was obtained with satisfactory intra‐ and inter‐day relative standard deviations of 0.4–4.4% (= 3) and 1.1–5.5% (= 3), respectively. Batch‐to‐batch reproducibility was acceptable with relative standard deviations <9.7%. The hydrophilic magnetic nanoparticle featured with quaternary ammonium groups showed high analytical potential for acidic analytes in environmental water samples.  相似文献   
35.
Four novel phloroglucinol derivatives, garcinielliptones A (1), B (2), C (3), D (4), a novel triterpenoid, garcinielliptone E (5), and three known compounds were isolated from the seeds of Garcinia subelliptica. The structures, including relative configurations, were elucidated by means of spectroscopic data. Known compounds garsubellin A (6) and garcinielliptin oxide (7) showed potent inhibitory effects on the release of beta-glucuronidase, and beta-glucuronidase and histamine, respectively, from peritoneal mast cells stimulated with compound 48/80 in a concentration-dependent manner with IC(50) values of 15.6+/-2.5, and 18.2+/-3.6 and 20.0+/-2.7 microM, respectively. Compound 7 showed potent inhibitory effects on the release of beta-glucuronidase and lysozyme from neutrophils stimulated with formyl-Met-Leu-Phe(fMLP)/cytochalasin B (CB) in a concentration-dependent manner with IC(50) values of 15.7+/-3.0 and 23.9+/-3.2 microM, respectively. Compound 7 also showed potent inhibitory effect on superoxide formation from neutrophils stimulated with fMLP/CB also in a concentration-dependent manner with an IC(50) value of 17.9+/-1.5 microM.  相似文献   
36.
A series of mononuclear metal complexes of Co(III), Ni(II) and Cu(II) with 2‐(2,4‐dichlorobenzamido)‐N′‐(3,5‐di‐tert‐butyl‐2‐hydroxybenzylidene)benzohydrazide ( LH 3 ) have been synthesized and characterized using various physico‐chemical, spectroscopic and single crystal X‐ray diffraction techniques. Structural studies of [Co( LH )( LH 2 )]·H2O ( 4 ) revealed the presence of both amido and imidol tautomeric forms of LH 3 , resulting in a distorted octahedral geometry around the Co(III) ion. [Ni( LH )(H2O)]·H2O ( 5 ) and [Cu( LH )(H2O)]·H2O ( 6 ) are isomorphous structures and crystallize in the monoclinic P21/c space group. The crystal structures of 4 , 5 and 6 are stabilized by hydrogen bonds formed by the enclathrated water molecules, C‐H···π and π···π interactions. Complexes along with the ligand ( LH 3 ) were screened for their in vivo anti‐inflammatory activity (carrageenan‐induced rat paw edema method) and in vitro antioxidant activity (DPPH free radical scavenging assay). Metal complexes have shown significant anti‐inflammatory and antioxidant potential.  相似文献   
37.
Chemical investigation of the Taiwanese gorgonian coral Junceella juncea resulted in the isolation of four new briarane‐type diterpenoids, juncenolides H, I, J, and K ( 1 – 4 ). Their structures were determined on the basis of spectroscopic analysis, especially 1‐ and 2D‐NMR. The inhibitory effects of compounds 1 – 4 on superoxide‐anion generation and elastase release by human neutrophils were evaluated.  相似文献   
38.
Gynura procumbens (Lour.) Merr. is traditionally used as a raw material for making dumplings or steamed stuffed buns, and its fresh leaves are boiled with water for tea. Herein, we established an ultra‐high–performance liquid chromatography–quadrupole time‐of‐flight mass spectrometry (UHPLC–Q‐TOF–MS/MS) combined with characteristic ion filtration (CIF) strategy to rapidly screen active ingredients with antioxidant and anti‐inflammatory properties in G. procumbens. This strategy involved screening the active part of G. procumbens using antioxidation and anti‐inflammatory activity assays; discovering the active compounds by speculating on the active site's chemical composition by UHPLC–Q‐TOF–MS/MS plus CIF; and verifying the active compounds' activities. The ethyl acetate extract (EEAF) of G. procumbens was the major active site. Eighty‐one compounds were identified from the EEAF using UHPLC–Q‐TOF–MS/MS plus CIF. Furthermore, polyphenols such as cynarine, isochlorogenic acids A and isochlorogenic acids C have excellent antioxidizing and anti‐inflammatory activities. This study provides a practical strategy for rapid in vitro screening of the antioxidizing and anti‐inflammatory activities of traditional vegetables and herbs and identification of active ingredients.  相似文献   
39.
The synthesis and characterization of Ru (II) terpyridine complexes derived from 4′ functionalized 2,2′:6′,2″‐terpyridine (tpy) ligands are reported. The heteroleptic complexes comprise the synthesized ligands 4′‐(2‐thienyl)‐ 2,2′:6′,2″‐terpyridine) or (4′‐(3,4‐dimethoxyphenyl)‐2,2′:6′,2″‐terpyridine and (dimethyl 5‐(pyrimidin‐5‐yl)isophthalate). The new complexes [Ru(4′‐(2‐thienyl)‐2,2′:6′,2″‐terpyridine)(5‐(pyrimidin‐5‐yl)‐isophthalic acid)Cl2] ( 9 ), [Ru(4′‐(3,4‐dimethoxyphenyl)‐2,2′:6′,2″‐terpyridine)(5‐(pyrimidin‐5‐yl)‐isophthalic acid)Cl2] ( 10 ), and [Ru(4′‐(2‐thienyl)‐2,2′:6′,2″‐terpyridine)(5‐(pyrimidin‐5‐yl)‐isophthalic acid)(NCS)2] ( 11 ) were characterized by 1H‐ and 13C‐NMR spectroscopy, C, H, N, and S elemental analysis, UPLC‐ESI‐MS, TGA, FT‐IR, and UV‐Vis spectroscopy. The biological activities of the synthesized ligands and their Ru (II) complexes as anti‐inflammatory, antimicrobial, and anticancer agents were evaluated. Furthermore, the toxicity of the synthesized compounds was studied and compared with the standard drugs, namely, diclofenac potassium and ibuprofen, using hemolysis assay. The results indicated that the ligands and the complex 9 possess superior anti‐inflammatory activities inhibiting albumin denaturation (89.88–100%) compared with the standard drugs (51.5–88.37%) at a concentration of 500 μg g?1. These activities were related to the presence of the chelating N‐atoms in the ligands and the exchangeable chloro‐ groups in the complex. Moreover, the chloro‐ and thiophene groups in complex 9 produce a higher anticancer activity compared with its isothiocyanate derivative in the complex 11 and the 3,4‐dimethoxyphenyl moiety in complex 10 . Considering the toxicity results, the synthesized ligands are nontoxic or far less toxic compared with the standard drugs and the metal complexes. Therefore, these newly synthesized compounds are promising anti‐inflammatory agents in addition to their moderate unique broad antimicrobial activity.  相似文献   
40.
A new 4‐hydroxy‐3‐carboxycoumarin ligand and its ruthenium(II) complexes ( 1 – 5 ) have been synthesized, characterized and screened for their in vitro antibacterial activity against a range of Gram‐positive and Gram‐negative bacteria. In addition, compounds 1 – 5 were investigated for antioxidant activities using superoxide radical, 2,2‐diphenyl‐1‐picrylhydrazyl radical and hydroxyl radical scavenging assays, in which most of them displayed significant antioxidant activities. Furthermore, compounds 1 – 5 were evaluated for anti‐inflammatory activity using indirect haemolytic and lipoxygenase inhibition assays and revealed good activity. The new complexes were characterized using spectroscopic methods in addition to elemental analysis.  相似文献   
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