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1.
Inorg Chem ; 63(8): 3637-3641, 2024 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-38341868

RESUMO

Two unique 22-core sandwich {[Mn6Mo6O37]Ln3[MnMo6O24]} (Ln = La or Pr) units have been assembled, featuring an undisclosed {Mn6Mo6} cluster. This assembly is subsequently integrated into two three-dimensional polyoxometalate organic frameworks, which exhibit one-dimensional hydrophilic hexagonal channels formed by six intertwined 63 helical chains, leading to effective proton conduction primarily facilitated by an abundance of water molecules within the channels.

2.
Org Biomol Chem ; 22(6): 1186-1193, 2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38214570

RESUMO

An azido-radical-triggered cyclization of N-(o-cyanobiaryl)acrylamides with TMSN3via a C(sp3)-N/C(sp2)-C(sp3)/C(sp2)-N bond formation cascade is described. This reaction features mild conditions and high bond-forming efficiency, making it an efficient method for the construction of azide-substituted pyridophenanthridines.

3.
Angew Chem Int Ed Engl ; : e202417548, 2024 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-39445657

RESUMO

Heterometallic cluster-based materials offer the potential to incorporate multiple functionalities, leveraging the aggregation effects of clusters and translating this heterogeneity and complexity into unexpected properties that are more than just the sum of their components. However, the rational construction of heterometallic cluster-based materials remains challenging due to the complexity of metal cation coordination and structural unpredictability. This minireview provides insights into a general synthetic strategy based on Hard and Soft Acids and Bases (HSAB) theory, summarizing its advantages in the designed synthesis of discrete heterometallic clusters (intracluster assembly) and infinite heterometallic cluster-based materials (intercluster assembly). Furthermore, it emphasizes the potential to exploit the intrinsic properties of mixed components to achieve breakthroughs across a broad range of applications. The insights from this review are expected to drive the progress of heterometallic cluster-based materials in a controllable and predictable manner.

4.
Biochem Biophys Res Commun ; 641: 168-176, 2023 01 22.
Artigo em Inglês | MEDLINE | ID: mdl-36528956

RESUMO

Autism spectrum disorder (ASD) is a complex disease with unclear etiology. Studies have shown that ferroptosis is also related to ASD progression, but the specific mechanism is still unclear. Valproic acid (VPA) induced neuronal ferroptosis in vitro. Mechanistic studies showed that both VPA and ferroptosis inducers promoted the expression of DDIT4 in neurons, thereby inhibiting the activation of the PI3K/Akt pathway. DDIT4 increased the accumulation of ROS, MDA and Fe2+, inhibited neuronal viability and downregulated GPX4 expression by inactivating the PI3K/Akt pathway. Ferroptosis inhibitors reversed the anti-survival effect of DDIT4, indicating that DDIT4 enhances ferroptosis through the PI3K/Akt pathway, thereby inhibiting neuronal viability. Further in vivo experiments found that autistic mice had high levels of ROS, MDA and Fe2+, increased DDIT4 expression, and downregulated expression levels of GPX4, p-PI3K and p-Akt; after downregulation of DDIT4 expression, the accumulation of ROS, MDA and Fe2+ was significantly reduced, while the expression levels of GPX4, p-PI3K and p-Akt were upregulated, indicating that DDIT4 knockdown reduces ferroptosis in autistic mice. In addition, DDIT4 downregulation, PI3K/Akt pathway activation, and ferroptosis inhibitors all improved social behavior deficits, repetitive stereotyped and compulsive behaviors, anxiety and exploratory behaviors in autistic mice, but PI3K/Akt pathway inhibitors significantly blocked the rescue of abnormal behaviors by DDIT4 downregulation in autistic mice. Therefore, downregulation of DDIT4 expression ameliorates abnormal behaviors in autism by inhibiting ferroptosis via the PI3K/Akt pathway, indicating that DDIT4, the PI3K/Akt pathway and ferroptosis have key roles in autism.


Assuntos
Transtorno do Espectro Autista , Transtorno Autístico , Ferroptose , Animais , Camundongos , Transtorno do Espectro Autista/tratamento farmacológico , Transtorno do Espectro Autista/genética , Fosfatidilinositol 3-Quinases/farmacologia , Proteínas Proto-Oncogênicas c-akt , Regulação para Baixo , Espécies Reativas de Oxigênio , Ácido Valproico/farmacologia , Fatores de Transcrição/farmacologia
5.
J Org Chem ; 88(7): 4528-4535, 2023 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-36913662

RESUMO

A copper-catalyzed cascade multicomponent reaction for synthesizing ditriazolyl diselenides from azides, terminal alkynes, and elemental selenium has been developed. The present reaction features utilizing readily available and stable reagents, high atom-economy, and mild reaction conditions. A possible mechanism is proposed.

6.
Inorg Chem ; 62(42): 17093-17101, 2023 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-37800965

RESUMO

The construction of polyoxometalate (POM)-based coordination polymers, in the presence of a nitrogen heterocyclic ligand, is intriguing due to the potential for obtaining diverse structures. These structures exhibit extensive application possibilities in the fields of proton conductivity and magnetism. Herein, four new POM-based polynuclear coordination polymers with the formulas of {[Fe2(btb)3(H2O)2(SiW12O40)]·3H2O}n (1), {[Cd2(btb)2(H2O)6(HPMoVI10MoV2O40)]·2H2O}n (2), {[Co3(OH)2(btb)2(H2O)5(HPMoVI10MoV2O40)]·7H2O}n (3), and {[Cu3(OH)(btb)2(H2O)(HP2Mo5O23)]·6H2O}n (4) have been prepared using the V-type 1,3-bis(4H-1,2,4-triazole-4-yl)benzene (btb) ligand. Compounds 1 and 2 feature similar two-dimensional (2D) structures, derived from the binuclear Fe2N6 and Cd2N4 subunits connected by tridentate btb ligands. Meanwhile, in compound 3, hexanuclear Co6(OH)4 units are bound by quadridentate btb ligands forming a 2D layer with the same 4-c sql topology simplification as compounds 1 and 2. In compound 1, Keggin-type polyoxoanions are monodentate-coordinated to metal ions and suspended on the 2D structure, while, in compounds 2 and 3, they act as discrete counterions residing in the interstitial spaces between two adjacent layers, thereby extending the 2D structures into 3D structures through hydrogen bonding interactions. In compound 4, trinuclear Cu3(OH) subunits are further constructed into a 3D framework through cooperation with four tridentate and quadridentate btb ligands as well as Strandberg-type anions. Furthermore, the proton conduction of the four compounds has been investigated. They display high proton conductivities at 358 K and 98% RH with powdered samples, which are 1.26 × 10-3, 1.24 × 10-3, 3.24 × 10-4, and 2.57 × 10-4 S cm-1, respectively. Interestingly, by mixing with Nafion, the composite membranes of compounds 2 and 4 exhibit enhanced proton conductivities, measuring at 4.87 × 10-2 and 1.28 × 10-2 S cm-1, respectively, at 358 K and 98% RH, which suggests excellent potential for applications. In addition, compounds 1, 3, and 4 display antiferromagnetic behaviors due to similar magnetic interactions. This work can provide research insights into the assembly of 2D POM-based coordination polymers with nitrogen heterocyclic ligands and Keggin-type POMs and further promote their research progress in proton conduction.

7.
BMC Health Serv Res ; 23(1): 49, 2023 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-36653848

RESUMO

BACKGROUND: Immune checkpoint inhibitors (ICIs) and targeted treatments have improved the health outcomes of patients with advanced melanoma. However, due to the high cost of novel therapies, it is crucial to evaluate their value by considering both effectiveness and cost. To compare the cost-effectiveness of these novel agents (atezolizumab-vemurafenib-cobimetinib, vemurafenib-plus-cobimetinib, dabrafenib-plus-trametinib, and encorafenib-plus-binimetinib) for first-line treatment of metastatic melanoma with the BRAFV600 mutation. METHODS: A patient-level model was developed to project the health outcomes of 4 strategies for patients with advanced melanoma. We estimated transition probabilities from the IMspire150 (ClinicalTrials.gov, NCT02908672), COMBI-AD (NCT01682083), and COLUMBUS (NCT01909453) trials using a parametric survival model. All health outcomes, including direct cost, quality-adjusted life-years (QALYs) and the incremental cost-effectiveness ratio (ICER), were estimated from the US payer perspective. Lifetime cost, QALYs, life-years (LYs), and ICERs were calculated. Univariable and probabilistic sensitivity analyses were performed to test model robustness, along with multiple scenario analyses. RESULTS: Of the 4 competing strategies, atezolizumab-vemurafenib-cobimetinib produced the best health outcomes, and the vemurafenib-cobimetinib strategy was the least expensive option. Atezolizumab-vemurafenib-cobimetinib, dabrafenib-plus-trametinib, and vemurafenib-cobimetinib formed the cost-effective frontier, indicating that the ordered ICERs were $325,113/QALYs for dabrafenib-plus-trametinib vs. vemurafenib-cobimetinib strategies and $2,247,500/QALYs for atezolizumab-vemurafenib-cobimetinib vs. dabrafenib-plus-trametinib strategies. Encorafenib-plus-binimetinib was dominated by the other 3 competing strategies. The drug price and first-line utility significantly influenced the model utcomes. CONCLUSIONS: For BRAF-mutant advanced melanoma, the vemurafenib-cobimetinib strategy could be considered the most cost-effective treatment at the willingness-to-pay threshold of $150,000.


Assuntos
Melanoma , Neoplasias Cutâneas , Humanos , Inibidores de Checkpoint Imunológico/uso terapêutico , Vemurafenib/efeitos adversos , Análise Custo-Benefício , Proteínas Proto-Oncogênicas B-raf/genética , Proteínas Proto-Oncogênicas B-raf/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Melanoma/tratamento farmacológico , Melanoma/genética , Melanoma/patologia , Neoplasias Cutâneas/tratamento farmacológico , Neoplasias Cutâneas/genética , Neoplasias Cutâneas/patologia
8.
Zhongguo Zhong Yao Za Zhi ; 48(19): 5326-5336, 2023 Oct.
Artigo em Zh | MEDLINE | ID: mdl-38114122

RESUMO

For the first time, this study evaluated the gender differences and mechanisms of the antidepressant effects of raw Rehmanniae Radix(RRR) based on the classic depression model with traditional Chinese medicine syndrome of Yin deficiency and internal heat. The depression model with Yin deficiency and internal heat was established by the widely recognized and applied method of thyroxine induction of the classic depression model with Yin deficiency and internal heat(chronic unpredictable mild stress). Male and female mice were simultaneously treated with RRR. The study analyzed indicators of nourishing Yin and clearing heat, conventional antidepressant efficacy test indicators, and important biomolecules reflecting the pathogenesis and prevention and treatment mechanisms of depression, and conducted a correlation analysis of antidepressant efficacy, Yin-nourishing and heat-clearing efficacy, and biological mechanism in different genders, thereby comprehensively assessing the antidepressant effects of RRR on depression of Yin deficiency and internal heat, as well as its gender differences and mechanisms. RRR exhibited antidepressant effects in both male and female mouse models, and its antidepressant efficacy showed gender differences, with a superior effect observed in females. Moreover, the effects of RRR on enhancing or improving hippocampal neuronal pathology, nucleus-positive areas, postsynaptic dense area protein 95, and synaptophysin protein expression were more significant in females than in males. In addition, RRR significantly reversed the abnormal upregulation of nuclear factor(NF)-κB/cyclooxygenase 2(COX2)/NOD-like receptor thermal protein domain associated protein 3(NLRP3) pathway proteins in the hippocampus of both male and female mouse models. The antidepressant effects of RRR were more pronounced in depression female mice with Yin deficiency and internal heat syndrome, possibly due to the improvement of neuronal damage and enhancement of neuroplasticity. The antidepressant mechanisms of RRR for depression with Yin deficiency and internal heat syndrome may be associated with the downregulation of the NF-κB/COX2/NLRP3 pathway to reduce neuronal damage and enhance neuroplasticity.


Assuntos
Proteína 3 que Contém Domínio de Pirina da Família NLR , Deficiência da Energia Yin , Masculino , Feminino , Camundongos , Animais , Fatores Sexuais , Ciclo-Oxigenase 2 , NF-kappa B , Antidepressivos/farmacologia
9.
J Org Chem ; 87(6): 4183-4194, 2022 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-35234480

RESUMO

Free radical carbochloromethylations of ortho-cyanoarylacrylamides and N-(arylsulfonyl)acrylamides have been developed by employing simple alkyl chlorides as the chloromethyl source. The transformations are characterized by wide functional group compatibility and utilizing readily available reagents, thus providing efficient methods for constructing polychloromethyl-substituted quinoline-2,4-diones and α-aryl-ß-polychloromethylated amides.

10.
Inorg Chem ; 61(23): 8629-8633, 2022 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-35649285

RESUMO

Two unique polyoxometalate (POM)-encapsulated tubular materials with the formula K(H2O)6[M6(btp)6(H2O)22](P2W18O62)3(Hbtp)5(btp)3·52H2O [M = Mn (1) and Co (2); btp = 2,6-bis(1,2,4-triazol-1-yl)pyridine] were designed and synthesized based on the Dawson POM and V-type btp ligand, as confirmed by IR, X-ray diffraction (XRD), and element analysis. Single-crystal XRD analyses of compound 1 show that two kinds of remarkable metal-organic supramolecular nanotubes, including trigonal and hexagonal nanotubes, are constructed along the c-axis direction via π···π-packing interactions between {Mn3(btp)3} rings and the btp ligands, of which [α-P2W18O62]6- anions are confined in channels, making the entire structure extraordinarily stable. Meanwhile, the coordinated [α-P2W18O62]6- anion within the hexagonal channel makes the channel highly hydrophilic and attracts a number of guest water molecules to fill in the free space, conducive to proton transport. Therefore, the single-crystal sample of 1 exhibits a high proton conductivity of 6.39 × 10-3 S cm-1 along one-dimensional channels, 30 times higher than that of a pellet sample at 358 K and 98% relative humidity.

11.
J Org Chem ; 86(12): 8216-8225, 2021 06 18.
Artigo em Inglês | MEDLINE | ID: mdl-34085512

RESUMO

Novel decarboxylative oxyacyloxylation of propiolic acids has been developed. This reaction provides an efficient access to alkynyl-containing α-acyloxy ketones from readily available starting materials and exhibits significant functional group tolerance. Furthermore, oxyacyloxylation of terminal alkynes and aliphatic propiolic acids was also developed. A possible reaction mechanism is proposed based on mechanistic studies.


Assuntos
Alcinos , Cetonas , Catálise , Estrutura Molecular
12.
Inorg Chem ; 60(2): 1264-1273, 2021 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-33400532

RESUMO

Four novel isopolymolybdate-based coordination polymers (CPs), constructed from 2,6-bis(1,2,4-triazol-1-yl)pyridine (btp), 1,3-bis(4H-1,2,4-triazol-4-yl)benzene (btb), and 3,5-bis(1-imidazolium)pyridine (bip), have been synthesized under a hydrothermal method: {[Co(btp)(H2O)2(ß-Mo8O26)0.5]·3H2O}n (1), [Ni(btp)(H4Mo6O22)0.5]n (2), [Co(btb)(H2O)(ß-Mo8O26)0.5]n (3), and {[Co(Hbip)2(H2O)2(γ-Mo8O26)]·6H2O}n (4). Complex 1 exhibits one 3D framework with an unexpected 3-nodal 2,4,6-c net topology containing the 1D {ß-Mo8O26}n chains, 6-connected CoII centers, and V-type coordinated btp ligands. The neighboring [Mo6O22]4- anions of complex 2 are bridged by the NiII centers to build one 2D {Ni2(Mo6O22)} network, which is arranged into the 3D framework through the weak π···π stacking interactions. In compound 3, one 3D framework is formed by the adjacent 1D {Co2(btp)2}n chains connected by {ß-Mo8O26}n units, which demonstrates a rare 4,6-c fsc topology. In complex 4, one 2D {Co(Hbip)2(γ-Mo8O26)} layer with a (4, 4) network is connected to one 3D hydrogen-bonding framework via N-H···O and O-H···O hydrogen bonds. Magnetic data indicate that complexes 1 and 4 exhibit antiferromagnetic behaviors, whereas complexes 2 and 3 reveal spin-canting magnetic behavior and metamagnetic behavior, respectively. In addition, the proton conductivity of complexes 3 and 4 was investigated, showing that compound 4 has good proton conductivity at 85 °C and a relative humidity of 98% RH.

13.
J Org Chem ; 85(15): 9944-9954, 2020 08 07.
Artigo em Inglês | MEDLINE | ID: mdl-32646216

RESUMO

A photoredox decarboxylative coupling of N-hydroxyphthalimide esters with aldimines is reported for synthesizing α-amino esters. A broad scope of alkyl radicals generated under visible light irradiation adds to glyoxylate aldimines in reliably good to excellent yields. Adding inorganic bases such as potassium carbonate significantly enhanced the yields by suppressing the umpolung side reaction. The computation study suggests that the base facilitates hydrogen atom transfer from the radical cation of Hantzsch ester to the N-centered radical intermediates. Introducing amino acid side chains into natural products and drug molecules by this method is demonstrated.

14.
J Org Chem ; 85(5): 3576-3586, 2020 03 06.
Artigo em Inglês | MEDLINE | ID: mdl-31984747

RESUMO

A copper-catalyzed decarboxylative cycloaddition of propiolic acids, azides, and arylboronic acids is described. The present reaction provides an efficient and convenient method for the synthesis of various fully substituted 1,2,3-triazoles from readily available starting materials. A possible mechanism is proposed.

15.
CNS Spectr ; 25(4): 493-501, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-31659946

RESUMO

Autism spectrum disorder (ASD) is a neurodevelopmental disorder that is characterized by deficits in social interactions and perseverative and stereotypical behavior. Growing evidence points toward a critical role for synaptic dysfunction in the onset of ASD, and synaptic function is influenced by glial cells. Considering the evidence that neuroinflammation in ASD is mediated by glial cells, one hypothesis is that reactive glial cells, under inflammatory conditions, contribute to the loss of synaptic functions and trigger ASD. Ongoing pharmacological treatments for ASD, including oxytocin, vitamin D, sulforaphane, and resveratrol, are promising and are shown to lead to improvements in behavioral performance in ASD. More importantly, their pharmacological mechanisms are closely related to anti-inflammation and synaptic protection. We focus this review on the hypothesis that synaptic dysfunction caused by reactive glial cells would lead to ASD, and discuss the potentials of antineuroinflammatory therapy for ASD.


Assuntos
Anti-Inflamatórios/uso terapêutico , Transtorno do Espectro Autista/tratamento farmacológico , Neuroglia/efeitos dos fármacos , Transmissão Sináptica , Animais , Anti-Inflamatórios/farmacologia , Humanos , NF-kappa B/metabolismo , Neuroglia/metabolismo
16.
J Asian Nat Prod Res ; 22(8): 732-737, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31154855

RESUMO

Two new flavonoids, 5,4'-dihydroxy-6,7-furanbavachalcone (1), 1″-methoxy-6,7-furanflavanone (2), together with five known compounds (3-7), were isolated from the seeds of Psoralea corylifolia. Their structures were elucidated by IR, UV, NMR, HRESMS experiments, and comparison of their NMR data with previously reported data. All compounds were evaluated for in vitro inhibitory activity against PTP1B. Additionally, the isolated compounds (1-6) displayed moderate inhibitory effects against PTP1B with IC50 values ranging from 10.3 ± 0.9 to 25.1 ± 1.6 µM.


Assuntos
Proteína Tirosina Fosfatase não Receptora Tipo 1 , Psoralea , Flavonoides , Estrutura Molecular , Sementes
17.
J Cell Biochem ; 120(2): 1754-1762, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30160788

RESUMO

The pathogenic mechanism of autism is complex, and current research has shown that long noncoding RNAs (lncRNAs) may play important roles in this process. The antisense lncRNA of SH3 and multiple ankyrin repeat domains 2 (Shank2-AS) is upregulated in patients with autism spectrum disorder (ASD), whereas the expression of its sense strand gene Shank2 is downregulated. In neuronal cells, Shank2-AS and Shank2 can form a double-stranded RNA and inhibit Shank2 expression. Overexpression of Shank2-AS decreases neurite numbers and lengths, thereby inhibiting the proliferation of neuronal cells and promoting their apoptosis. Overexpression of Shank2 inhibits the abovementioned effects of Shank2-AS, and transfection of a vector containing the 10th intron of Shank2 (Shank2-AS is reverse-transcribed from this region) also blocks the function of Shank2-AS. Shank2 small interfering RNA plays a role similar to Shank2-AS. Therefore, Shank2-AS is abnormally expressed in patients with ASD and may affect the structure and growth of neurons by regulating Shank2 expression, thereby facilitating the development of ASD.

18.
J Org Chem ; 84(12): 8177-8184, 2019 06 21.
Artigo em Inglês | MEDLINE | ID: mdl-31122013

RESUMO

The first Fe(OTf)2-catalyzed radical addition to aldimines with Hantzsch ester as a two-hydrogen atom donor is reported. The tin-free reaction works well for electron-deficient substrates and provides a potentially useful approach to α-branched amines and α-amino acids.

19.
J Org Chem ; 84(6): 3419-3430, 2019 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-30807154

RESUMO

Structurally complex 2(5 H)-furanones are potentially challenging targets for ring-closing metathesis (RCM). A hydrogen bonding-guided RCM strategy was developed in this study to provide 3-substituted and 3,4-disubstituted 2(5 H)-furanones in moderate to high yields with broad functional group tolerance. A workup procedure using ethylenediamine-derived polyamines such as tetraethylenepentylamine was also established to effectively remove Ru residues in products.

20.
Org Biomol Chem ; 17(43): 9447-9455, 2019 11 06.
Artigo em Inglês | MEDLINE | ID: mdl-31638134

RESUMO

An oxidative decarboxylative cascade cyclization of α-keto acids with 2-cyano-3-arylaniline-derived acrylamides was developed. This cascade reaction exhibits a broad substrate scope, and provides an efficient access to carbonyl-containing pyrido[4,3,2-gh]phenanthridines. A possible mechanism is proposed.

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