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Aster tataricus L.f. is highly valued for its rich reserves of bioactive compounds. Our research focused on the identification of previously unreported compounds found within the ethanol extract of A. tataricus. Through meticulous spectroscopic analyses and computational methods like NMR calculations and ECD, we successfully elucidated the structures of five novel compounds termed tatarisides A-E (1-5), alongside two known compounds (6, 7). The anti-inflammatory assays conducted yielded noteworthy results, particularly in relation to compounds 1 and 5. These compounds exhibited significant potential in inhibiting the release of NO in LPS-induced RAW 264.7 cells, as evidenced by their respective IC50 values of 17.81 ± 1.25 µM and 13.32 ± 0.84 µM. The discovery of these new compounds adds to the existing knowledge of A. tataricus's chemical composition and potential applications.
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Aster , Estrutura Molecular , Aster/química , Extratos Vegetais/química , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/química , EtanolRESUMO
BACKGROUND: Neuronal intranuclear inclusion disease (NIID) is a rare highly heterogeneous disease. In this paper, we present a case of NIID featured in cortical involvement in left hemisphere of brain and the imaging changes in the process of the disease. CASE PRESENTATION: A 57-year-old female was hospitalized due to recurrent attacks of headache with cognitive impairment and tremor for 2 years. The symptoms of headache episodes were reversible. The characteristic radiologic change was high intensity signal involving the grey matter-white matter junction on the brain diffusion-weighted imaging (DWI), which existed in the frontal lobe and then extended backwards. Atypical features on fluid-attenuated inversion recovery (FLAIR) sequences showing small patchy high signals in the cerebellar vermis. High signals and edema were detected on FLAIR images along the cortex of the left occipito-parieto-temporal lobes, expanding and gradually shrinking in the follow-up visit. Besides, cerebral atrophy and bilateral symmetrical leukoencephalopathy were also detected. Skin biopsy and genetic testing confirmed the diagnosis of NIID. CONCLUSION: Except for typical radiological change strongly suggesting NIID, it is also necessary to notice the insidious symptoms of NIID combining with some atypical imaging features to make an early diagnosis. Skin biopsies or genetic testing should be carried out early in patients with highly suspected NIID.
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Doenças Neurodegenerativas , Feminino , Humanos , Pessoa de Meia-Idade , Doenças Neurodegenerativas/complicações , Doenças Neurodegenerativas/diagnóstico , Doenças Neurodegenerativas/patologia , Imageamento por Ressonância Magnética , Imagem de Difusão por Ressonância Magnética , CefaleiaRESUMO
Oxidation and removal of highly toxic sulfides and amines are particularly important for environmental and human security but remain challenging. Here, incorporating an excellent photosensitizer, donor-acceptor-donor (D-A-D)-type 4,4'-(benzo[c][1,2,5]thiadiazole-4,7-diyl)dibenzoic (H2L), into metal-organic frameworks (MOFs) has been manifested to promote the charge separation, affording four three-dimensional (3D) MOFs (isostructural 1-Co/1-Zn with Co2/Zn2 units, and 2-Gd/2-Tb with Gd/Tb-cluster chains) as photocatalysts in the visible light-driven air-O2-mediated catalytic oxidation and removal of hazardous phenylsulfides and benzylamines. Impressively, structure-property correlation illustrated that the transition metal centers assembled in MOFs play an important role in the photocatalytic activity, and we can conclude that 1-Zn can be a robust heterogeneous catalyst possessing good light adsorption and fast charge separation in oxidation removal reactions of both benzylamines and phenylsulfides under visible light irradiation and room temperature with excellent activity/selectivity, stability, and reusability.
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In this article, two undescribed amides (1-2) with an unusual (2-formyl-5-hydroxymethyl)pyrroyl-butylamine moiety were obtained from the Physochlainae Radix. Comprehensive spectroscopic studies, including NMR and HR-ESI-MS, coupling with spectroscopic data comparisons were used to determine structures. Anti-inflammatory assay results showed that new amides possessed significant inhibitory activities of the NO production of LPS-induced RAW 264.7 cells, with IC50 values of 17.52±1.68â µM and 20.37±2.42â µM, respectively.
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Amidas , Anti-Inflamatórios , Animais , Camundongos , Amidas/farmacologia , Anti-Inflamatórios/farmacologia , Células RAW 264.7 , Estrutura MolecularRESUMO
Organic dyes as non-noble metal photosensitizers have attracted increasing attention due to their environmental friendliness and sustainability but suffer from fast deactivation and low stability. Here, we reported a fruitful strategy by the confinement and stabilization of visible light-active signal unit organic dyes within the metal-organic frameworks (MOFs) and developed a series of heterogeneous photocatalysts dye@UiO-66s [dye = fluorescein (FL)/rhodamine B (RhB)/eosin Y (EY), UiO-66s = UiO-66, and Bim-UiO-66]. It has been demonstrated that the encapsulated dyes can effectively sensitize MOF hosts and dominate the band structures and photocatalytic activities of dye@UiO-66s regardless of the ligand functionalization of MOFs. Photocatalytic experiments showed that these dye@UiO-66s exhibit enhanced activities relative to free dyes and among them, FL@Bim-UiO-66 displays excellent efficiencies toward the green synthesis of new carbon-bridged annulations, [1,2,5]thiadiazole[3,4-g]benzoimidazoles in the yield of up to 98% at room temperature with outstanding stability and reusability. Furthermore, the intramolecular cyclization intermediate was captured and characterized by the single-crystal X-ray diffraction analysis.
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OBJECTIVE: To observe the effects of transcutaneous acupoint stimulation (TEAS) on sleep quality and inflammatory factor in frail elderly patients undergoing laparoscopic colorectal cancer surgery. METHODS: A total of 100 frail elderly patients undergoing elective laparoscopic colorectal cancer surgery were randomly divided into an observation group and a control group, 50 cases in each one. Patients in the observation group received TEAS, 30 min before surgery until the end of surgery, at 18:00 on the day of surgery and on the 1st, 2nd and 3rd day after surgery (30 min each time). TEAS was delivered at bilateral Neiguan (PC 6), Shenmen (HT 7) and Hegu (LI 4). The disperse-dense wave of 2 Hz/100 Hz was selected, and the maximal stimulation intensity depended on patient's tolerance. The operation procedure in the control group was same as the observation group, but without electric stimulation exerted. The 1st day before surgery and on the 1st, 3rd and 7th day after surgery, the scores of Pittsburgh sleep quality index (PSQI) and Athens insomnia scale (AIS), as well as the serum levels of C reactive protein (CRP) and interleukin-6 (IL-6) were observed in the patients of two groups. At 24 h, 48 h and 72 h after surgery, the score of pain visual analogue scale (VAS) was recorded in the two groups, as well as the pressing times of analgesic pump and the usage of flurbiprofen axetil during analgesic stage. The occurrence of post operative adverse reactions was observed in the patients of two groups. RESULTS: On the 1st and 3rd day after surgery, except the usage of hypnotic drug scores, the scores of each item and the total scores of PSQI, as well as AIS scores were all increased in the two groups compared with those of 1 day before surgery (P<0.05); and the scores in the observation group were lower than those in the control group (P<0.05). On the 7th day after surgery, the scores of each item and the total scores of PSQI, and AIS scores were not different statistically in comparison between the two groups (P>0.05). On the 1st, 3rd and 7th day after surgery, serum levels of CRP and IL-6 were all increased in the patients of two groups when compared with those of 1 day before surgery (P<0.05), serum levels CRP and IL-6 in the patients of the observation group were lower than those of the control group (P<0.05). The VAS scores of 24 h, 48 h and 72 h after surgery, the pressing times of analgesic pump, the frequency and dosage of the remedies were not different statistically between the two groups (P>0.05). CONCLUSION: TEAS can effectively improve sleep quality and reduce inflammatory reaction in frail elderly patients undergoing laparoscopic colorectal cancer surgery.
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Pontos de Acupuntura , Neoplasias Colorretais , Idoso , Humanos , Idoso Fragilizado , Interleucina-6 , Qualidade do Sono , Proteína C-ReativaRESUMO
We aimed to investigate the efficacy and safety of rivaroxaban for acute and long-term management of cerebral venous sinus thrombosis (CVST). This study reviewed CVST-diagnosed patients admitted to the First Affiliated Hospital of Guangxi Medical University from January 2015 to December 2020. The primary outcome was a composite of recurrent thrombosis or major bleeding events. The secondary efficacy outcomes included a disease recovery time (DRT) presenting the time from admission to the endpoint as recovery (the modified Rankin scale [mRS] score [0-1]) within 30 and 90 days, and length of hospital stay (LHS). Patients treated with rivaroxaban (38) and warfarin (45) were enrolled in the final analysis. The primary outcome had no significant difference (5.3% vs 11.1%, P = .576) between the 2 groups. The secondary efficacy outcome regarding the median 30-d DRT was 17 days (95% confidence interval [CI], 14.6-19.4) in the rivaroxaban group, compared with 26.0 days (95% CI, 16.8-35.2) in the warfarin group (hazard ratio, 1.806; 95% CI, 1.051-3.103; log-rank P = .026). Two groups have a significant difference in LHS (P = .041). Patients with cerebral edema, intracerebral hemorrhage, and mild/moderate disability (admission mRS score [2-3]) treated with rivaroxaban recovered faster than those with warfarin (log-rank P < .05). Patients with cerebral edema, intracerebral hemorrhage, and mild/moderate disability treated with rivaroxaban had a shorter recovery time than those treated with warfarin within 1 month from admission, indicating that rivaroxaban a promising convenient therapy for CVST, helping them speedily restore social functions.
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Edema Encefálico , Trombose dos Seios Intracranianos , Humanos , Rivaroxabana/efeitos adversos , Inibidores do Fator Xa/efeitos adversos , Anticoagulantes/efeitos adversos , Edema Encefálico/induzido quimicamente , Edema Encefálico/tratamento farmacológico , População do Leste Asiático , China , Varfarina/efeitos adversos , Hemorragia Cerebral/tratamento farmacológico , Trombose dos Seios Intracranianos/tratamento farmacológico , Resultado do TratamentoRESUMO
Effective and rapid capture of heavy metal oxo-anions from wastewater is a fascinating research topic, but it remains a great challenge. Herein, benzimidazole and -CH3 groups were integrated into UiO-66 in succession via a step-by-step linker modification strategy that was performed by presynthesis modification (to give Bim-UiO-66) and subsequently by postsynthetic ionization (to give Bim-UiO-66-Me). The UiO-66s (UiO-66, Bim-UiO-66, and Bim-UiO-66-Me) were applied in the removal of heavy metal oxo-anions from water. The two benzimidazole derivatives (Bim-UiO-66 and Bim-UiO-66-Me) showed much better performance than UiO-66, as both the initial sorption rate and sorption capacities decreased in the order Bim-UiO-66-Me > Bim-UiO-66 > UiO-66. The maximum performances of Bim-UiO-66 are 5.1 and 1.7 times those of UiO-66. Remarkably, Bim-UiO-66-Me shows 7.5 and 3.0 times better performance than UiO-66. The higher absorptivity of cationic Bim-UiO-66-Me compared with UiO-66 can be attributed to a strong Coulombic interaction as well as an anion-π interaction and hydrogen bonding between the benzimidazolium functional group and heavy metal oxo-anions. The as-synthesized Bim-UiO-66-Me not only provides a promising candidate for application in removal of heavy metal oxo-anions in wastewater treatment but also opens up a new strategy for the design of high-performance adsorbents.
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Metais Pesados , Poluentes Químicos da Água , Adsorção , Ânions , Benzimidazóis , Cátions , Estruturas Metalorgânicas , Ácidos Ftálicos , Poluentes Químicos da Água/análiseRESUMO
A metal-free inactive C(sp3)-H bond functionalization of thioethers with styrenes using TBHP as an initiator and DBU as a base has been developed. This transformation has broken through the low activity of thioethers and realized moderate yields. Herein extended experiments were conducted to confirm the radical relay process, reaction energy and intermediate transformations.
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Three new compounds, polygalapyrone A (1), tenuiside G (2) and polygalapyrrole A (3), together with two known compounds (4-5) were isolated by silica gel, ODS and preparative HPLC from the aerial part of Polygala tenuifolia. Their structures were elucidated by spectrum analysis and compared with findings from the literature. The anti-inflammatory effects of those compounds were investigated in vitro.
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Polygala , Polygala/química , Cromatografia Líquida de Alta Pressão , Componentes Aéreos da PlantaRESUMO
The abuse of antibiotics has triggered the rise of drug-resistance bacteria, which has seriously threatened public health globally. As a result, carrying out efficient and accurate antibiotic and bacteria identification are quite significant but challenge. Herein, an unprecedented Cd-MOF-based sensor, [CdL]n [1, H2L = 4-(2-methyl-1H-benzo[d]imidazol-1-yl) isophthalic acid] with multiple fluorescence response behaviours towards antibiotics and bacteria was developed. Single-crystal X-ray diffraction revealed that 1 is a mesomeric 2D bilayer, which is comprised of two opposite chiral mono-layers, each assembled by left-handed or right-handed helixes. More interestingly, 1 represented multiplex detection capability towards antibiotics and bacteria through two detection behaviors: toward nitro-antibiotics and chlortetracycline (CTC) via fluorescent quenching, while toward Staphylococcus albus (S. albus) via fluorescent enhancement. Remarkably, 1 showed a low limit of detection (LOD, 47 CFU/mL) accompanied with specificity in the detection of S. albus compared to other bacteria, such as Staphylococcus aureus, Acinetobacter baumannii, Klebsiella pneumonia, Pseudomonas aeruginosa and Escherichia coli. In addition, the LOD could reach to ppm level for nitro-antibiotics and CTC. Moreover, the practical application of 1 was further reinforced through the detection of nitro-antibiotics and CTC, as well as S. albus in fetal calf serum and river water.
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Antibacterianos , Cádmio , Antibacterianos/uso terapêutico , Testes de Sensibilidade Microbiana , Staphylococcus aureus , Staphylococcus epidermidisRESUMO
Atherosclerosis was an important pathophysiological basis of atherothrombotic stroke, and phosphodiesterase 4D (PDE4D) polymorphism (SNP83/rs966221) was reported to be associated with the susceptibility to atherothrombotic stroke. Aim of the present study was to explore the potential association between SNP83 and carotid atherosclerosis (CAS). 204 southern Chinese Han participants were divided into two groups according to the carotid intima-media thickness (IMT) of the carotid artery: CAS group (carotid IMT ≥ 1.0 mm) and non-CAS group (carotid IMT < 1.0 mm). Carotid IMT was measured by color Doppler ultrasound. The PDE4D SNP83 polymorphism was determined by SNaPshot technique. Our study found that SNP83 was associated significantly with CAS susceptibility under the dominant, overdominant and codominant models. After adjusting for age, gender, low-density lipoprotein cholesterol, Hemoglobin A1c, cigarette smoking, hypertension history, and diabetes mellitus history, the association still remained significant (dominant model: crude OR = 2.373, 95% CI: 1.268-4.442, P = 0.007; adjusted OR = 3.129, 95% CI: 1.104-8.866, P = 0.032; overdominant model: crude OR = 1.968, 95% CI: 1.043-3.714, P = 0.037; adjusted OR = 2.854, 95% CI: 1.005-8.108, P = 0.049; codominant: crude OR = 2.102, 95% CI: 1.110-3.979, P = 0.023; adjusted OR = 2.984, 95% CI: 1.047-8.502, P = 0.041). Carotid IMT of carriers with CT + CC genotypes was higher than carriers with TT genotype (P = 0.016). Our results indicated that the SNP83/rs966221 located on PDE4D gene was significantly associated between CAS susceptibility and carotid IMT independently of conventional risk factors in a southern Chinese Han population.
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Povo Asiático/genética , Doenças das Artérias Carótidas/genética , Nucleotídeo Cíclico Fosfodiesterase do Tipo 4/genética , Predisposição Genética para Doença , Polimorfismo de Nucleotídeo Único , Alelos , Biomarcadores , Doenças das Artérias Carótidas/diagnóstico , Espessura Intima-Media Carotídea , China , Estudos de Associação Genética , Genótipo , Humanos , Fatores de RiscoRESUMO
OBJECTIVE: The purpose of this study was to investigate associations between two single nucleotide polymorphisms (SNPs) rs505922 and rs532436 in ABO gene and the risk of small artery occlusion stroke (SAO) in southern Chinese Han population. METHODS: Our case-control study comprising 121 patients with SAO and 136 controls. All participants were Han population of southern China. IS sub-type was defined on the basis of the TOAST criteria. SAO was strictly diagnosed after a systematic physical examination and neuroimaging via MRI. Genotype analysis was conducted by the snapshot technique. RESULTS: The distribution of rs532436 genotype between these two groups showed a statistically significant difference (P = 0.048) while that of rs505922 genotype showed no significant difference (P = 0.572). SNP rs532436 was significantly associated with SAO in overdominant model (GA vs. GG + AA) after adjusting for age, hypertension history, diabetes history and cigarette smoking (adjusted OR = 2.03, 95% CI: 1.14-3.62, P = 0.016). However, under all genetic models, the rs505922 polymorphism failed to show association with SAO. CONCLUSION: The resultsindicate that rs532436 polymorphism in ABO gene may have association with SAO in southern Chinese Han population.
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Sistema ABO de Grupos Sanguíneos/genética , Arteriopatias Oclusivas/genética , Etnicidade , Galactosiltransferases/genética , Polimorfismo de Nucleotídeo Único , Acidente Vascular Cerebral/genética , Idoso , Estudos de Casos e Controles , China , Feminino , Estudo de Associação Genômica Ampla , Heterozigoto , Humanos , Masculino , Pessoa de Meia-IdadeRESUMO
OBJECTIVE: To observe the effect of transcutaneous electrical acupoint stimulation (TEAS) of different acupoint combinations on postoperative nausea and vomiting (PONV) and serum motilin (MTL) content in patients undergoing laparoscopic surgery, so as to provide evidence for clinical selection of suitable acupoint compatibility. METHODS: A total of 140 patients undergoing elective laparoscopic surgery were randomly divided into general anesthesia (GA) control, TG2 ï¼»Neiguan (PC6) + Hegu (LI4)ï¼½, TG3 ï¼»PC6 + LI4 + Zusanli (ST36)ï¼½, and TG4 ï¼»PC6 + LI4 + ST36 + Sanyinjiao (SP6)ï¼½ groups, with 35 cases in each group. Patients of the TG2, TG3 and TG4 groups received TEAS (2 Hz/100 Hz, 3-8 mA) of the above mentioned acupoint (bilateral) groups for 30 min before the induction of anesthesia until the end of the operation. Patients of the GA control group received intravenous injection of Midazolam, Sufentanil, Propofol, Rocuronium Bromide, etc. The blood sample (4 mL) from the right median cubital vein was collected at the time of patient's entry, 12 and 24 h after surgery, respectively, for measuring MTL concentration by enzyme-linked immunosorbent assay. The incidence of early and late PONV and changes of PONV degree within 24 h after surgery were recorded. RESULTS: The serum MTL concentrations were significantly decreased at 12 h after surgery in all the 4 groups (P<0.05), and decreased at 24 h after surgery in GA and TG2 groups vs their own pre-surgery (P < 0.05), and considerably higher at both 12 and 24 h after surgery in the TG2, TG3 and TG4 groups than in the GA control group (P<0.05), and also evidently higher in the TG3 and TG4 groups than in the TG2 group (P<0.05). The incidence of PONV was significantly lower in the TG2, TG3 and TG4 groups than in the GA control group in the early and late periods (except TG2 group) of surgery (P<0.05). The number of patients with PONV grade â was significantly larger in the TG2, TG3 and TG4 groups than in the GA control group at 24 h after surgery (P<0.05), suggesting a mild PONV in more patients undergoing TEAS. CONCLUSION: TEAS has a preventive effect on PONV in patients undergoing laparoscopic surgery, which may be related to its effect in reducing serum MTL concentration. The preventive effect of TEAS of PC6 + LI4 + ST36 and PC6 +LI4 + ST36 + SP6 is similar and better than TG2 (two acupoints) group.
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Náusea e Vômito Pós-Operatórios/terapia , Estimulação Elétrica Nervosa Transcutânea , Pontos de Acupuntura , Humanos , Laparoscopia/efeitos adversos , Motilina , Náusea e Vômito Pós-Operatórios/etiologiaRESUMO
BACKGROUND: Previous genome-wide association studies have found two single nucleotide polymorphisms (SNP) rs7692387 and rs1842896 located on or near the GUCY1A3 gene were associated with coronary artery disease (CAD). GUCY1A3 was considered to be involved in the process of atherosclerosis, but there was little information about the association between genotypic polymorphisms of the GUCY1A3 and large artery atherosclerotic (LAA) stroke. This study aimed to investigate the associations between the GUCY1A3 rs7692387, rs1842896 polymorphisms and LAA stroke susceptibility. METHODS: A total of 298 LAA stroke patients and 300 control subjects from a southern Chinese Han population were included. SNaPshot technique was used for genotype analysis. Associations between genotypes and LAA stroke susceptibility were analyzed with logistic regression model. RESULTS: Our study found that under the recessive model (TT vs. GT + GG), the GUCY1A3 rs1842896 polymorphism was significantly correlated with LAA stroke (OR = 1.48, 95%CI: 1.07-2.04, P = 0.018). After adjustment for its effects on age, gender, cigarette smoking, total cholesterol, low-density lipoprotein cholesterol, HbA1c, hypertension, diabetes mellitus, and CAD, the rs1842896 TT genotype retained association with increased susceptibility to LAA stroke (recessive model: adjusted OR = 1.96, 95%CI: 1.22-3.17, P = 0.006). However, association between rs7692387 polymorphism with LAA stroke was not observed. CONCLUSION: Our results indicate that the GUCY1A3 rs1842896 polymorphism is an LAA stroke risk factor in Southern Han Chinese.
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Aterosclerose/genética , Hipertensão/genética , Guanilil Ciclase Solúvel/genética , Acidente Vascular Cerebral/genética , Idoso , Artérias/patologia , Aterosclerose/epidemiologia , Aterosclerose/patologia , China/epidemiologia , Feminino , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Genótipo , Humanos , Hipertensão/epidemiologia , Hipertensão/patologia , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Acidente Vascular Cerebral/epidemiologia , Acidente Vascular Cerebral/patologiaRESUMO
Based on systematic DFT calculations, silaborane-based superhalogen anions, which obey the Wade-Mingos rule, are shown to be capable of giving rise to superacids via their combination with protons. Compared to previous carborane-based systems, the acidities of the composites here are stronger in both the gas phase and solution phase. Thus, the potential of candidates based on silaborane could be greater than those based on carborane in the search for ultra-strong acidic systems. Within a given group, a higher superhalogen anion vertical electron detachment energy (VDE) generally leads to stronger acidity. This consistency arises from the dominant role of the VDE, as established through the decomposition of the gas-phase acidity into different contributions. Thus, constructing superacids from superhalogens is a rational route whose future should be positive. Besides the VDE, other effects, i.e., the deformation energy (DE) and bond dissociation energy (BDE), could also be crucial, especially in terms of the differences between the acidities of composites belonging to different groups. A comparison between the results in the gas phase and solution phase indicates that complete calculations of both gas-phase ΔGacid and solution-phase pKa values are necessary to obtain an unbiased description of the acidity. The solvation free energies of the participants in the deprotonation process, especially the conjugate acid, are responsible for the discrepancies between gas phase and solution phase behavior.
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Based on various comparable salen ligands, three synthesized CuIINaI-complexes present efficient catalytic activities for the coupling and cyclization reaction of 1,2-diaminopropane with nitriles towards 2-imidazolines. The catalytic results show that salen ligands with an electron-donating substituent and small steric hindrance improve the catalytic activity.
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The construction route of organic superacids from the combination of organic superhalogens and protons is verified to be a rational one based on a systematic theoretical study covering different planar conjugated backbones, e.g., [C5H5]- and [BC5H6]-, and electron-withdrawing substituents, e.g., -F, -CN and -NO2. In both the gas phase and the solution phase, the acidities of the composites here have a consistent strengthening with the increase of the vertical electron detachment energy of the superhalogen part. Decomposition of the acidity into different contributions further verifies the dominant role of the superhalogen part in the variation of the acidity. Thus, tuning of the acidity of systems of this type could be achieved via rational design of the constituent part of the superhalogen. That is to say, the design of a novel organic superacid with enhanced properties could be guided by the search for a new strong superhalogen of organic nature eventually. Having provided important contributions to the topic of superhalogens, theoretical calculation should be trusted to provide useful guidance for the research of organic superacids and could be expected to promote related experimental studies in the near future.
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A new ligand, rac-(R,S)-3,9-bis(pyridin-3-yl)-2,4,8,10-tetraoxaspiro[5.5]undecane ((R,S)-bptu), is synthesized, and five novel complexes, namely, {[Cu[(R,S)-bptu]Cl2]·0.5NMP}n (1), {[Zn[(R,S)-bptu]Cl2]·CH3CN}n (2), {Cd2[(R,S)-bptu]2Cl4(NMP)2}n (3), {[Cd[(R,S)-bptu]2Cl2]·2CH3CN}n (4), and {Cd3[(R,S)-bptu]2Cl6(DMF)2}n (5), (NMP = N-methyl-2-pyrrolidone, DMF = N,N-dimethylformamide), are obtained via a layered diffusional reaction. (R,S)-bptu and complexes 1-5 are characterized by single-crystal X-ray diffraction, element analyses, powder X-ray diffraction (PXRD), and Fourier transform infrared spectroscopy (FTIR) and thermogravimetric analyses (TGA). Complexes 1-3 show three different 1D structures: 1 is a mesomeric looped chain, 2 is a racemic helix compound, and 3 is a mesomeric zigzag chain, while 4 and 5 are two different mesomeric 2D structures, of which 4 is a 2D wave-like layer and 5 is a 2D cellular layer. Structural diversity indicates that the coordination preferences (cis- and trans-configurations) of (R,S)-bptu play a leading role in the self-assembly of complexes: cis-bptu tends to form one-dimensional structures 1-3, while trans-bptu is easier to construct higher dimensional structures 4-5. Secondly, the different transition metal atom M(ii) adopts diverse geometry in 1-5: Cu(ii) adopts square pyramidal geometry in 1, Zn(ii) employs a tetrahedron configuration in 2, and especially in 3-5, Cd(ii) displays a trigonal bipyramidal configuration, cis-cis-trans, cis and trans octahedral configuration. Finally, the different solvent system, the coordinated/free solvent, and the secondary building units (SBUs) affect the diversification of the structure. A variable temperature magnetic susceptibility investigation manifests that antiferromagnetic interactions exist between the neighbouring metal ions in 1. Furthermore, the luminescence properties of 2-5 are investigated in the solid state at room temperature, and 4 shows highly selective and sensitive sensing for Fe3+ ions.
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A series of 20 composite structures, consisting of superhalogen and noble gas (Ng) hydrides, was explored via high-level coupled-cluster single, double and perturbative triple excitations calculations in this work. The existence of these composites, as local minima on the potential energy surface, arises from the charge transfer from the Ng hydride part to the superhalogen moiety. Clearly, this transfer could lead to stabilizing the interaction of the ionic type between the two components. The driving force of the charge transfer should be the high vertical electron detachment energy (VDE) of the superhalogen part leading to its enough capability of extracting the electron from the Ng hydride moiety. However, except triggering the ionic attractive interaction, there is nomonotonic correlation between the VDE value and the thermodynamic stability of the whole composite. This counter-intuitive result actually originates from the fact that, irrespective of various superhalogens, only two of their F ligands interact with the Ng atoms directly. Thus, although leading to higher VDE values, the increase in the number of electronegative ligands of the superhalogen moiety does not affect the stabilizing interaction of the composites here directly. In other words, with the necessary charge transfer generated, further increase of the VDE does not ensure the improvement of the thermodynamic stabilities of the whole composite. Moreover, in the transition state of the exothermic dissociation channel, more F atoms will give rise to higher probability of additional attractions between the F and H atoms which should lower the energy barrier. That is to say, increasing VDE, i.e., having more F atoms in many cases, will probably reduce the kinetic stability. Knowing the inevitable existence of the exothermic channel, kinetic stability is crucial to the ultimate goal of experimental observation of these Ng hydrides. Thus, in some cases, only the superhalogen itself may not provide enough information for the correct prediction on the properties of the whole composites. The understanding of the superhalogen-based composites will provide valuable information on the functional properties as well as the application potential of superhalogen clusters. Thus, the corresponding researches should focus on not only the superhalogen itself but also other related aspects, especially the details of the interaction between different parts.