ABSTRACT
Cyclization of the ether enyne 1 catalyzed by [Ru]NCCH3(+) ([Ru] = Cp(PPh3)2Ru) in CHCl3 generates a diastereomeric mixture of the substituted tetrahydropyran 11. Presumably, formation of an allenylidene complex is followed by a cyclization by nucleophilic addition of the olefinic group to Cγ of the ligand giving a boat-like six-membered ring. The diastereoselectivity is controlled by the 1,3-diaxial interaction. The vinylidene complex 7, a precursor of 11, is obtained from 1 and [Ru]Cl. In a mixture of MeOH/CHCl3, the domino cyclization of 1 further affords 14a, a chromene product catalytically. The second cyclization proceeds via nucleophilic addition of the resulting olefinic unit to Cα of 7. But the ether enyne 3 with a cyclopentyl ring on the olefinic unit undergoes only single cyclization due to steric effect. The propargyl alcohol and the two terminal methyl groups on the olefinic unit shape the cyclization. Thus, similar all-carbon 1,n-enynes (n = 7, 8, 9) 4-6 each with an aromatic linker undergo direct domino cyclization catalyzed by [Ru]NCCH3(+), to give derivatives of tricyclic fluorene, phenanthrene and dibenzo[7]annulene, respectively, with no intermediate observed.
ABSTRACT
In recent years, there has been an increase in the scientific production of youth soccer. However, a panoramic map of research on this subject does not exist. The aim of this study was to identify global research trends in youth soccer over time, among the main levels of analysis: sources, authors, documents, and keywords. The bibliometric software Biblioshiny was used to analyze 2606 articles in Web of Science (WoS) published between 2012 and 2021. The main conclusion is that US and UK scholars dominate the research; the topics of research are changing with the real needs, and research on the topic of performance has been of interest to scholars; talent identification and development, performance, injury prevention, and concussion are the studies of interest to scholars in this area. This finding, which offers a global picture of youth soccer research over time, can help future research in this or similar domains.
ABSTRACT
The reactions of [Cp(PPh(3))(2) RuCl] (Cp=cyclopentadienyl) with phenyl propargylic alcohol 1a, with a 3-thiophene group, are explored. The carbene complex 2a, obtained exclusively from this reaction at low temperature, contains the naphthothiophene group, which is formed through a new cyclization process between the thiophene group and the inner carbon of the triple bond. Details of this process have been revealed by conducting the reaction at room temperature, affording the allenylidene complex 3a as a side product. Complex 3a is not converted into 2a, indicating that the cyclization takes place while the triple bond is π coordinated to the metal center. Complex 2a reacts with oxygen in the presence of NEt(3) at room temperature to afford, in high yield, naphthothiophene aldehyde 4a, ONEt(3), OPPh(3), and [Cp(PPh(3))(2)RuCl]. Molecular O(2) is likely activated by coordination to the metal center when one of the phosphane ligands dissociates. Then, NEt(3) promotes the oxygenation process by reacting with the coordinated O(2) to afford ONEt(3) and possibly an unobserved oxo-carbene complex. Coupling of the oxo and carbene ligands then yields 4a and [Cp(PPh(3))(2) RuCl] in CHCl(3). In a solvent system containing MeOH, the oxygenation reaction affords a mixture of 4a and naphthothiophene ester 5a-1. The reactions of [Cp(dppf)RuCl] (dppf=1,1'-bis(diphenylphosphino)ferrocene) with 1a, also afford the carbene complex 2a', 4a, and 5a, which have been characterized by X-ray diffraction analyses. For the phenyl propargylic alcohol 1b, with a 2-thiophene substituent, different naphthothiophene aldehyde and ester compounds are also obtained in high yields through a similar cyclization process followed by oxygenation under mild conditions.
ABSTRACT
Depression is a common psychiatric comorbidity in patients with epilepsy, especially those with temporal lobe epilepsy (TLE). The aim of this study was to assess changes in high mobility group box protein 1 (HMGB1) expression in epileptic patients with and without comorbid depression. Sixty patients with drug-resistant TLE who underwent anterior temporal lobectomy were enrolled. Anterior hippocampal samples were collected after surgery and analyzed by immunofluorescence (n = 7/group). We also evaluated the expression of HMGB1 in TLE patients with hippocampal sclerosis and measured the level of plasma HMGB1 by enzyme-linked immunosorbent assay. The results showed that 28.3% of the patients (17/60) had comorbid depression. HMGB1 was ubiquitously expressed in all subregions of the anterior hippocampus. The ratio of HMGB1-immunoreactive neurons and astrocytes was significantly increased in both TLE patients with hippocampal sclerosis and TLE patients with comorbid depression compared to patients with TLE only. The ratio of cytoplasmic to nuclear HMGB1-positive neurons in the hippocampus was higher in depressed patients with TLE than in nondepressed patients, which suggested that more HMGB1 translocated from the nucleus to the cytoplasm in the depressed group. There was no significant difference in the plasma level of HMGB1 among patients with TLE alone, TLE with hippocampal sclerosis, and TLE with comorbid depression. The results of the study revealed that the translocation of HMGB1 from the nucleus to the cytoplasm in hippocampal neurons may play a previously unrecognized role in the initiation and amplification of epilepsy and comorbid depression. The direct targeting of neural HMGB1 is a promising approach for anti-inflammatory therapy.
Subject(s)
Epilepsy, Temporal Lobe , Epilepsy , HMGB1 Protein , Humans , Sclerosis/metabolism , Sclerosis/pathology , HMGB1 Protein/metabolism , Epilepsy, Temporal Lobe/surgery , Epilepsy, Temporal Lobe/metabolism , Epilepsy, Temporal Lobe/pathology , Hippocampus/pathology , Epilepsy/surgery , Epilepsy/metabolism , Gliosis/pathology , Cytoplasm/metabolismABSTRACT
Asymmetric dimethylarginine (ADMA) is an endogenous inhibitor of nitric oxide synthase and plays a significant role in the pathogenesis of arteriovenous fistula (AVF) dysfunction. The aim of this study is to evaluate the effect of far-infrared (FIR) therapy on the maturation and patency of newly-created AVFs in patients with advanced diabetic kidney disease (DKD) as well as the concurrent change in plasma ADMA. The study enrolled 144 participants with advanced DKD where 101 patients were randomly allocated to the FIR therapy group (N = 50) and control group (N = 51). Patients receiving FIR therapy had a decreased AVF failure rate within 12 months (16% versus 35.3%; p = 0.027); decreased incremental change of ADMA concentration at the 3rd and 12th month; increased AVF blood flow at the 1st, 3rd, and 12th month; increased 3-month physiologic maturation rate (88% versus 68.6%; p = 0.034); increased 1-year unassisted AVF patency rate (84% versus 64.7%; p = 0.017); and increased clinical AVF maturation rate within 12 months (84% versus 62.7%; p = 0.029) compared to the control group. The study demonstrates that FIR therapy can reduce the incremental changes in plasma ADMA concentration, which may be associated with the improvement of AVF prognosis in patients with advanced DKD.
ABSTRACT
Three new aristololactam derivatives, aristololactam W-Y (1-3), and three known compounds (4-6) were isolated from the fruits of Aristolochia contorta Bunge. Compounds 1 and 2 represent the first example of an N-CH2OCH3 aristololactam derivative from natural products. Their structures were elucidated by 1D/2D NMR and HRESIMS spectra. All of the isolated compounds were evaluated for their insecticidal activity against 4th instar larvae of Aedes aegypti. Compound 4 displayed insecticidal activity with LC50 value of 3.54 µg/mL.
Subject(s)
Aristolochia/chemistry , Aristolochic Acids/isolation & purification , Insecticides/isolation & purification , Phytochemicals/isolation & purification , Aedes , Animals , China , Fruit/chemistry , Larva , Molecular StructureABSTRACT
Consecutive cyclization reactions of phenyl propargyl alcohols 1 and 2 are catalyzed by [Ru]NCCH(3)(+) ([Ru] = Cp(PPh(3))(2)Ru) in cosolvent CHCl(3)/MeOH at 60 °C, to afford the fused cyclic compounds 11a (R = Me) and 10a (R = Me), respectively.