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131.
Neocinnamomum caudatum (Lauraceae) plant is used in the traditional system of medicine and is considered a potential source of edible fruits, spices, flavoring agents and biodiesel. The leaves, bark and roots of the species are used by local communities for the treatment of inflammatory responses, such as allergies, sinusitis and urinary tract infections. However, there is no scientific evidence to support the molecular mechanism through which this plant exerts its anti-inflammatory effect. The aim of the current research was to characterize the chemical constituents of bark (NCB) and leaf (NCL) essential oil of N. caudatum and to elucidate its anti-inflammatory action in lipopolysaccharide (LPS)-treated RAW 264.7 cells. Essential oils extracted by hydrodistillation were further subjected to gas chromatography mass spectrometry (GC-MS) analysis. The major constituents in bark essential oil identified as β-pinene (13.11%), α-cadinol (11.18%) and α-pinene (10.99%), whereas leaf essential oil was found to be rich in β-pinene (45.21%), myrcene (9.97%) and α-pinene (9.27%). Treatment with NCB and NCL at a concentration of 25 µg/mL exerted significant anti-inflammatory activity by significantly reducing LPS-triggered nitric oxide (NO) production to 45.86% and 61.64%, respectively, compared to the LPS-treated group. In the LPS-treated group, the production of proinflammatory cytokines, such as tumor necrosis factor (TNF)-α, interleukin (IL)-6 and IL-1β, decreased after treatment with essential oil, alleviating the mRNA levels of inducible nitric oxide synthase (iNOS) and cyclooxygenase (COX)-2. The essential oil also inhibited the production of intracellular ROS and attenuated the depletion of mitochondrial membrane potential in a concentration-dependent manner. Pretreatment with NCB also reduced nuclear factor kappa-B (NF-κB)/p65 translocation and elevated the levels of endogenous antioxidant enzymes in LPS-induced macrophages. The present findings, for the first time, demonstrate the anti-inflammatory potential of both bark and leaf essential oils of N. caudatum. The bark essential oil exhibited a significantly more important anti-inflammatory effect than the leaf essential oil and could be used as a potential therapeutic agent for the treatment of inflammatory diseases.  相似文献   
132.
Correction for ‘Expanding medicinal chemistry into 3D space: metallofragments as 3D scaffolds for fragment-based drug discovery’ by Christine N. Morrison et al., Chem. Sci., 2020, 11, 1216–1225, https://doi.org/10.1039/C9SC05586J.

The authors regret that in the original article, inhibitory values reported for some metallofragments were incorrect. Unfortunately, DMSO stock solutions of reportedly active ferrocene-based metallofragments were found to decompose in the presence of light, which resulted in inaccurate inhibition values. The authors maintain that the core conclusions of the paper are accurate and the utility of three-dimensional metal complexes for fragment-based drug discovery has merit.In the original article, ‘class A’ metallofragments are comprised of ferrocene derivatives (Fig. 1). Some of these ferrocene fragments (specifically those containing carbonyl groups) are reported as broadly inhibiting several protein targets. It was noted in our original report that the ferrocene scaffold was likely promiscuous due to its lipophilicity and potential redox activity, but that it might still serve as a useful metallofragment for fragment-based drug discovery (FBDD) campaigns. However, re-evaluation of these compounds against the influenza endonuclease (PAN) failed to reproduce our original inhibition results for the class A metallofragments using freshly prepared stocks, indicating a problem with the materials used in the original study.Open in a separate windowFig. 1Chemical structures of class A metallofragments.Several compounds from class A were originally reported as having near complete (100%) inhibition against PAN endonuclease at an inhibitor concentration of 200 μM (and2).2). However, when re-evaluated under identical conditions, using freshly prepared DMSO stock solutions, inhibition was only observed with one fragment of this class (A22, Fig. 1), with the previously reported highly active fragments (A4, A7–A21,
CompoundA1A2A3A4A5A7A8A9A10A11
Reported12 ± 6<1<145 ± 148 ± 7103 ± 5103 ± 453 ± 546 ± 790 ± 5
Corrected3 ± 10n.d.18 ± 36 ± 321 ± 59 ± 310 ± 54 ± 216 ± 410 ± 7
Open in a separate windowan.d. = not determined.
CompoundA12A14A15A16A17A18A19A20A21A22
Reported66 ± 526 ± 655 ± 719 ± 8100 ± 4107 ± 632 ± 880 ± 410 ± 1688 ± 9
Corrected9 ± 410 ± 518 ± 115 ± 65 ± 3<111 ± 9<1< 193 ± 1
Open in a separate windowReported and re-evaluated percent inhibition values of representative metallofragments against PAN endonuclease at 200 μM inhibitor concentration. Each compound was tested in triplicate from either two or three independent experimentsa
CompoundA1B1C1D1E1F1G1
Reported12 ± 64 ± 670 ± 2320 ± 1118 ± 982 ± 516 ± 6
Re-evaluated<519 ± 875 ± 1114 ± 9<510 ± 14<5
Open in a separate windowan.d. = not determined.
CompoundH1I1J1K1L1M1DPBA
Reported31 ± 626 ± 725 ± 699 ± 312 ± 426 ± 4n.d.
Re-evaluated25 ± 9<541 ± 683 ± 330 ± 854 ± 597 ± 1
Open in a separate windowIn the original article, one representative member of each metallofragment class was assessed for stability by NMR. Compound A1 (ferrocene) proved stable in DMSO and class A metallofragments were stored as DMSO stocks at −80 °C, but were not consistently protected from light. As noted above, many of the derivatives in class A contain a ferrocenyl carbonyl motif. It has been previously reported that ferrocenyl ketones can undergo photoaquation (λ > 280 nm) in wet DMSO to produce a monocyclopentadienyliron cation, the anionic ligand, and free cyclopentadiene.1 Suspecting issues with photostability, we dissolved several of the ferrocenyl fragments in DMSO-d6, exposed them to ambient room light (fluorescent light bulb), and monitored stability by NMR. Indeed, photoinstability was confirmed by the observance of free cyclopentadienyl peaks appearing in the 1H NMR spectrum (Fig. 2). It should also be noted that while the fresh stock of A22 retained significant inhibition against PAN, it also exhibits sensitivity to light in DMSO.Open in a separate windowFig. 2Compound A7 in DMSO-d6 (left) and after exposure to ambient light for 24 h (right) demonstrating the photoinstability of this compound.Based on these findings, the authors regret that the inhibitory data associated with class A metallofragments are incorrect, likely because of photodecomposition of these ferrocene derivatives. To confirm if other classes of metallofragments were correctly reported, a representative member of each class was evaluated against PAN endonuclease at an inhibitor concentration of 200 μM using freshly prepared DMSO stocks. Each compound was tested in triplicate in two or three independent experiments, with the addition of 2,4-dioxo-4-phenylbutanoic acid (DPBA) as a positive control.2 Fortunately, these experiments largely reproduced our original findings. Although several fragments showed slightly greater activity upon re-evaluation (J1, L1, M1, Fig. 3), only one fragment initially identified as a hit (>50% inhibition) failed to show activity when re-examined (F1, Fig. 3). Other than compound F1, all selected compounds designated as ‘hits’ (>50% inhibition) retained a high level of inhibitory activity upon re-evaluation. Taken together, the authors believe the inaccuracies stemming from photostability issues are limited to class A compounds; however, these inaccuracies would include all other inhibition data reported for class A compounds, including assay data against other enzyme targets, IC50 values, and thermal shift assay (TSA) binding data. Furthermore, the hit rate against each target is likely lower than reported, with PAN having an adjusted hit rate of ∼28% (20/71).Open in a separate windowFig. 3Chemical structures of representative metallofragments from each class re-examined for inhibition activity against PAN endonuclease.The authors maintain that three-dimensional metallofragments represent a useful new line of inquiry for FBDD and our ongoing studies seek to further test this hypothesis. The core message of our original study – the ability of metallofragments to be useful scaffolds for FBDD that occupy hard-to-access three-dimensional chemical space – remains unchanged. However, as demonstrated by our error, the authors acknowledge that metallofragments may pose unique challenges that must be carefully considered and controlled for when using them in FBDD campaigns.The authors would like to take this opportunity to thank the readers who alerted them to the concerns regarding the inhibitory activities and allowed them to reinvestigate. Both the authors and the Royal Society of Chemistry appreciate their support.The Royal Society of Chemistry apologises for these errors and any consequent inconvenience to authors and readers.  相似文献   
133.
On the sufficiency of the consistency-equations     
B. R. Seth 《Proceedings Mathematical Sciences》1937,5(6):518-521
  相似文献   
134.
Die Hydrolyse von Ammoniumsalzen in Gegenwart von Jodiden und Jodaten     
Seth E. Moody 《Fresenius' Journal of Analytical Chemistry》1907,46(12):777
Ohne Zusammenfassung  相似文献   
135.
Photochemical activation of a metal-organic framework to reveal functionality     
Tanabe KK  Allen CA  Cohen SM 《Angewandte Chemie (International ed. in English)》2010,49(50):9730-9733
  相似文献   
136.
New measurements of Cabibbo-suppressed decays of mesons with the CLEO-c detector     
Rubin P  Cawlfield C  Eisenstein BI  Karliner I  Kim D  Lowrey N  Naik P  Sedlack C  Selen M  White EJ  Wiss J  Shepherd MR  Besson D  Pedlar TK  Cronin-Hennessy D  Gao KY  Gong DT  Hietala J  Kubota Y  Klein T  Lang BW  Poling R  Scott AW  Smith A  Dobbs S  Metreveli Z  Seth KK  Tomaradze A  Zweber P  Ernst J  Severini H  Dytman SA  Love W  Mehrabyan S  Savinov V  Aquines O  Li Z  Lopez A  Mendez H  Ramirez J  Xin B  Huang GS  Miller DH  Pavlunin V  Sanghi B  Shipsey IP  Adams GS  Anderson M  Cummings JP  Danko I  Napolitano J  He Q  Insler J 《Physical review letters》2006,96(8):081802
Using of data collected with the CLEO-c detector, we report on first observations and measurements of Cabibbo-suppressed decays of D mesons in the following six decay modes: pi+ pi- pi0 pi0, pi+ pi+ pi- pi- pi0, pi+ pi0 pi0, pi+ pi+ pi- pi0, eta pi0, and omega pi+ pi-. Improved branching fraction measurements in eight other multipion decay modes are also presented. The measured D --> pi pi rates allow us to extract the ratio of isospin amplitudes A(DeltaI = (3/2) / A(DeltaI = (1/2)) = 0.420 +/- 0.014(stat) +/- 0.016(syst) and the strong phase shift of delta1 = (86.4 +/- 2.8 +/- 3.3) degrees, which is quite large and now more precisely determined.  相似文献   
137.
Synthesis, structure, and spectroscopy of phenylacetylenylene rods incorporating meso-substituted dipyrrin ligands     
Halper SR  Cohen SM 《Chemistry (Weinheim an der Bergstrasse, Germany)》2003,9(19):4661-4669
The synthesis, structure, and spectroscopic characterization of a series of phenylacetylenylene rodlike molecules containing dipyrromethene (dipyrrin) ligands are described. The combination of the phenylacetylenylene groups with the porphyrinogenic dipyrrin moieties results in a rich absorption spectroscopy for these compounds, although the fluorescence of the phenylacetylenylene moiety is quenched by presence of the dipyrrin chelator. The Cu(2+) and Fe(3+) complexes of these ligands have been prepared and three of these compounds have been structurally characterized by using single-crystal X-ray diffraction. Unlike other octahedral metal-dipyrrin complexes described to date, one of the iron complexes demonstrates ideal threefold symmetry in the solid-state. The elongated structure and high symmetry of these complexes suggests the use of these meso-substituted phenylacetylenylene ligands as an interesting class of extended, branched molecules for the construction of supramolecular architectures.  相似文献   
138.
Self-assembly of heteroleptic [Cu(dipyrrinato)(hfacac)] complexes directed by fluorine-fluorine interactions     
Halper SR  Cohen SM 《Inorganic chemistry》2005,44(12):4139-4141
Heteroleptic copper(II) complexes were synthesized from three different meso-substituted pyridyl- and quinoline-dipyrrinato ligands (3-pyrdpm, 3-quindpm, and 4-quindpm). Metal complexes were prepared with both acetylacetonate (acac) and hexafluoroacetylactonate (hfacac) ancillary ligands. The complexes undergo a self-complementary self-assembly process upon crystallization to generate a range of solid-state topologies including one-dimensional coordination polymers and discrete hexameric rings. The self-assembly of these molecular aggregates is driven by metal-ligand bonding, but is also modulated by fluorine-fluorine interactions. Perfluorination of the spectator ligand tends to generate more compact structures, which is attributed to aggregation of the perfluoromethyl groups. The results presented here demonstrate that fluorine-fluorine contacts can be used to modulate supramolecular structures in the solid state.  相似文献   
139.
Solvent relaxation of a room-temperature ionic liquid [bmim][PF6] confined in a ternary microemulsion     
Debabrata Seth  Palash Setua  Anjan Chakraborty  Nilmoni Sarkar 《Journal of Chemical Sciences》2007,119(2):105-111
In this paper we have reported the solvent and rotational relaxation of 1-butyl-3-methyl-imidazolium hexafluorophosphate ([bmim][PF6]) confined in tween 20/([bmim][PF6]/water microemulsion using coumarin 153 (C-153) as probe. The most interesting feature of our experiment was that we observed an increase in solvent relaxation time with increase in R (R = tween 20-to-[bmim][PF6] molar ratio). This is due to the fact that with increase in [bmim][PF6] content of the microemulsions, the microviscosity of the pool of the microemulsions increases, and motion of ions of [bmim][PF6] is hindered in the pool of microemulsions. Since motion of ions is responsible for solvation in room-temperature ionic liquids (RTILs), solvent-relaxation time increases with increase in R.  相似文献   
140.
Large relativistic effects in molecular properties of the hydride of superheavy element 111     
Michael Seth  Peter Schwerdtfeger  Michael Dolg  Knut Faegri  Bernd A. Hess  Uzi Kaldor 《Chemical physics letters》1996,250(5-6):461-465
Relativistic and electron correlation contributions in the hydride of the recently discovered superheavy element 111 were studied using ab-initio methods within different relativistic approaches. Relativistic effects decrease the (111)H bond distance by 0.42 Å. As a result of this large bond contraction, the bond distance of (111)H (1.51 Å) is comparable to that of the hydride of its lighter congener AuH (1.52 Å), but below that of AgH (1.60 Å). The dissociation energy is relativistically increased by approximately 1.2 eV and the stretching force constant is more than quadrupled from 1.1 mdyn/Å at the nonrelativistic level to 5.0 mdyn/Å at the relativistic level.  相似文献   
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