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1.
J Org Chem ; 89(11): 7899-7912, 2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38728220

RESUMO

An efficient, practical, and metal-free protocol for the synthesis of silicon-containing isoindolin-1-ones and deuterated analogues via the synergistic combination of an organic photoredox and hydrogen atom transfer process is described. This strategy features mild reaction conditions, high atom economy, and excellent functional group compatibility, delivering a myriad of structurally diverse and valuable products with good to excellent yields.

2.
Org Biomol Chem ; 22(20): 4047-4051, 2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38712523

RESUMO

Herein, electroreductive umpolung benzylic deuteration of p-QMs using cheap and easily accessible D2O as a deuterium source is reported. Various value-added benzylic deuterated diarylmethanes can be synthesized without the requirement of noble metal catalysts, redox reagents, and strong bases. The establishment of this protocol will provide an alternative strategy for acquiring benzylic deuterated diarylmethanes.

3.
Org Biomol Chem ; 22(28): 5724-5728, 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-38957074

RESUMO

Herein, a electroreductive carboxylation of benzylphosphonium salts was achieved by the cleavage of the C(sp3)-P bond, and various valuable arylacetic acids could be synthesized by this strategy. Also, based on control experiments and previous studies, a plausible reaction mechanism was proposed to explain the reaction process. The establishment of this procedure will provide a new paradigm for the functionalization of alkyl phosphonium salts.

4.
J Org Chem ; 88(20): 14640-14648, 2023 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-37773013

RESUMO

Magnesium-mediated reductive carboxylation of p-QMs with CO2 via an Umpolung strategy has been developed, which can be used for the preparation of various aryl acetic acids. This protocol featured high atom economy, mild conditions, and operational simplicity. The creation of this Umpolung carboxylation of p-QMs will unprecedentedly extend the application of p-QMs to nucleophilic reagents.

5.
J Org Chem ; 88(24): 17134-17143, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-38056421

RESUMO

It is significant to develop novel difluoromethylation methods because of the important roles of difluoromethyl groups in the medicinal chemistry and material industries. Here, we developed a novel difluoromethylation-carboxylation and difluoromethylation-deuteration method triggered by a difluoromethyl radical generated by electroreduction of stable and easily available difluoromethyltriphenylphosphonium bromide. Various molecules containing difluoromethyl and carboxyl or deuterium groups can be synthesized through this method. The establishment of this method will provide an alternative to radical difluoromethylation reactions.

6.
J Clin Apher ; 38(4): 368-375, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36420568

RESUMO

BACKGROUND: The value of double filtration plasmapheresis (DFPP) in severe hypertriglyceridemia-induced pancreatitis (sHTGP) is controversial. This study aimed to investigate the efficacy of DFPP on clinical outcomes in patients with sHTGP and the costs associated with the procedure. METHODS: Patients who underwent DFPP after admission between January 2016 and December 2021 were recruited. Data on lipid profile, clinical parameters, and costs were retrospectively collected and analyzed. RESULTS: Fifty sHTGP patients who received DFPP were enrolled. All of the lipid profile were significantly reduced and maintained a downward trend. The APACHE II score on admission was higher and the reduction after DFPP was more obvious (P < 0.05) in patients with higher triglyceride (TG) levels (≥33.9 mmol/L) than in patients with lower TG levels. More material fees were expended in the higher TG group due to more DFPP sessions (P < 0.05), but no significant differences existed in total hospital costs between the two groups. CONCLUSION: DFPP could rapidly and effectively reduce TGs to a safe level. APACHE II score reduction was obvious in patients with TGs ≥33.9 mmol/L and was associated with lipid profile changes. DFPP may benefit sHTGP patients with a TG level higher than the current initiation threshold.


Assuntos
Hiperlipidemias , Hipertrigliceridemia , Pancreatite , Humanos , Estudos Retrospectivos , Hipertrigliceridemia/complicações , Hipertrigliceridemia/terapia , Pancreatite/complicações , Pancreatite/terapia , Plasmaferese/métodos , Lipídeos , Filtração
7.
J Org Chem ; 87(5): 3567-3576, 2022 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-35133837

RESUMO

A novel photocatalytic method for the preparation of diarylmethyl silanes was reported through silyl radicals addition strategy to p-QMs (p-quinone methides). This protocol could tolerate a variety of functional groups affording the corresponding silylation products with moderate to excellent yields. The resulting silylation products could be easily converted into a series of bioactive GPR40 agonists and useful p-QMs precursors for the synthesis of compounds possessing both quaternary carbon centers and silicon substituents through simple operation. A plausible mechanism of silyl radicals to p-QMs was proposed on the basis of experimental results and previous literature.

8.
Blood ; 133(7): 730-742, 2019 02 14.
Artigo em Inglês | MEDLINE | ID: mdl-30552097

RESUMO

Increased macrophage phagocytosis of antibody-coated platelets, as well as decreased numbers and/or impaired function of CD4+CD25+Foxp3+ regulatory T (Treg) cells, has been shown to participate in the pathogenesis of immune thrombocytopenia (ITP). Low-dose histone deacetylase inhibitors (HDACi's) are anti-inflammatory and immunomodulatory agents that can enhance immunosuppression in graft-versus-host disease by increasing the number and function of Foxp3+ Treg cells, but it is unclear whether they have the potential to promote immune tolerance and platelet release in ITP. In this study, we performed in vitro and in vivo experiments and found that a low-dose HDACi (chidamide) alleviated thrombocytopenia in passive and active murine models of ITP. Further, low-dose HDACi's attenuated macrophage phagocytosis of antibody-coated platelets, stimulated the production of natural Foxp3+ Treg cells, promoted the peripheral conversion of T cells into Treg cells, and restored Treg cell suppression in vivo and in vitro. Finally, we confirmed that low-dose HDACi's could regulate CTLA4 expression in peripheral blood mononuclear cells through modulation of histone H3K27 acetylation. Low-dose HDACi treatment in ITP could be offset by blocking the effect of CTLA4. Therefore, we propose that low-dose chidamide administration has potential as a novel treatment for ITP in the clinic.


Assuntos
Aminopiridinas/administração & dosagem , Benzamidas/administração & dosagem , Tolerância Imunológica/imunologia , Leucócitos Mononucleares/imunologia , Púrpura Trombocitopênica Idiopática/imunologia , Linfócitos T Reguladores/imunologia , Acetilação , Adulto , Idoso , Animais , Antígeno CTLA-4/metabolismo , Relação Dose-Resposta a Droga , Feminino , Fatores de Transcrição Forkhead/metabolismo , Humanos , Tolerância Imunológica/efeitos dos fármacos , Leucócitos Mononucleares/efeitos dos fármacos , Leucócitos Mononucleares/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Pessoa de Meia-Idade , Prognóstico , Púrpura Trombocitopênica Idiopática/tratamento farmacológico , Púrpura Trombocitopênica Idiopática/metabolismo , Linfócitos T Reguladores/efeitos dos fármacos , Adulto Jovem
9.
J Asian Nat Prod Res ; 23(5): 429-435, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-32290693

RESUMO

One new spirocyclic lactone, terreinlactone C (1), and one new benzopyran derivative, 2,2-dimethyl-3-hydroxychroman-6-aldehyde (2), were discovered from the fungus Aspergillus terreus. The chemical structures of compounds 1 and 2 were elucidated by detailedly analyzing NMR and HRESIMS data. Compound 1 is the first natural product with a 1-oxaspiro[4.5]decan-2-one ring system and a possible biogenetic pathway is proposed. Two compounds were tested for their cytotoxic activities against five human cancer cell lines.[Formula: see text].


Assuntos
Benzopiranos , Lactonas , Aspergillus , Benzopiranos/farmacologia , Lactonas/farmacologia , Estrutura Molecular
10.
J Org Chem ; 85(7): 4740-4752, 2020 04 03.
Artigo em Inglês | MEDLINE | ID: mdl-32162916

RESUMO

A highly regioselective approach to access amide enol carbamates and carbonates 5a-5c', 7a-7h, and 9 was developed through Cu(OTf)2-catalyzed reactions of ynamides 4 with t-butyl carbamates 2 and 8 and t-butyl carbonates 6. Moreover, this strategy was successfully applied to generate amide enol carbamates 11a-11s and 14a-14f from imides 10 and 13 with ynamides through an N-Boc cleavage-addition ring-opening process. A range of substituents was amenable to this transformation, and the desired amide enol carbamates and carbonates were obtained in moderate to good yields.

11.
J Org Chem ; 84(2): 914-923, 2019 01 18.
Artigo em Inglês | MEDLINE | ID: mdl-30577693

RESUMO

An efficient asymmetric approach to access functionalized pyrido- and pyrrolo[1,2- c][1,3]oxazin-1-ones has been developed through a nucleophilic addition-cyclization process of N, O-acetal with ynamides. A number of substituted ynamides 8a-8o and 3-silyloxypyrrolidine or piperidine N, O-acetals 6a, 7 were amenable to this transformation, and the desired products 9a-9o, 10a-10m were obtained with excellent regioselectivities and outstanding diastereoselectivities. Moreover, chiral ynamides 14a-14f could also experience this addition-cyclization process to afford products 15a-15f in excellent yields.

12.
Org Biomol Chem ; 14(45): 10714-10722, 2016 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-27805230

RESUMO

A diastereoselective new approach for the synthesis of trans-4-hydroxy-5-allyl-2-pyrrolidinone 9 has been developed through In-mediated allylation of α-chiral aldimine 8 with allyl bromide. The stereochemistry at the C-2 stereogenic center of 9 was controlled by both the α-OTBS substitution and the sulfinamide moiety. The utility of this asymmetric allylation is demonstrated by the asymmetric syntheses of epohelmins A (4) and B (10).


Assuntos
Compostos Alílicos/química , Compostos Bicíclicos Heterocíclicos com Pontes/síntese química , Pirrolidinonas/química , Compostos Alílicos/síntese química , Compostos Bicíclicos Heterocíclicos com Pontes/química , Pirrolidinonas/síntese química , Estereoisomerismo , Compostos de Sulfônio/síntese química , Compostos de Sulfônio/química
13.
Zhongguo Zhong Yao Za Zhi ; 41(3): 396-402, 2016 Feb.
Artigo em Zh | MEDLINE | ID: mdl-28868853

RESUMO

In order to investigate the epigenetic variations between diploid and autotetraploid of Platycodon grandiflorus. The diploid buds of P. grandiflorus were soaked in the mixture of different concentration colchicines and 0.002 g•mL ⁻¹ dimethyl sulphoxide (DMSO).The identification of autotetraploid plants were based on morphological characteristics, chromosome number and flow cytometry. And then the level and pattern of DNA methylation explored by using the technology of methylation sensitive amplified polymorphism (MSAP).The result demonstrated that the buds soaked in 0.2% colchicines and 0.002 g•mL ⁻¹ DMSO solution for 12 h was ideal conditions to induce autotetraploid of P. grandiflorus, with induction rate of 32.0%.The diploid and tetraploid plants existed distinctly differences in morphological indexes.Totally,1 586 bands were amplified by 20 pairs of selective primers, of which 764 and 822 bands were detected in diploid and autotetraploid respectively. The total methylation ratio,full methylation ratio and hemimethylated ratio were 91.25%,61.25% and 30.65% in diploid of P. grandiflorus,respectively.However,the total methylation ratio,full methylation ratio and hemimethylated ratio of autotetraploid of P. grandiflorus were 86.13%,54.38% and 31.75%, respectively. Compared with diploid, the genomic DNA total methylate ratio and full methylation ratio of autotetration plants decreased by 6.02% and 7.14%.But the hemimethylated ratio of autotetraploid was higher than that of diploid, which more than 1.6%. All this results indicated that DNA methylation patterns have adjusted during the polyploidy process..


Assuntos
Variação Genética , Platycodon/genética , Tetraploidia , Cromossomos de Plantas/genética , Cromossomos de Plantas/metabolismo , Metilação de DNA , DNA de Plantas/genética , Platycodon/classificação , Platycodon/crescimento & desenvolvimento , Platycodon/metabolismo , Polimorfismo Genético
14.
Pak J Pharm Sci ; 29(4): 1217-21, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27393434

RESUMO

The protective potential of the methanol extract of Macrothelypteris oligophlebia rhizomes (MMO) for chronic non-bacterial prostatitis (CNP) in rats was investigated in the present study. Carrageenan-induced CNP in rats was established. Fifty rats were randomly divided into sham-operated (sham-ope) group, model group, positive control group (Cernilton at a dose of 148mg/kg body weight) and two MMO-treated groups (MMO at doses of 600mg/kg and 300 mg/kg body weight). The anti-prostatitis effect was evaluated by prostate index, the levels of interleukin-10 (IL-10), tumor necrosis factor alpha (TNF-α), cyclooxygenase-2 (COX-2) and prostaglandin E2 (PGE2), and histopathological examination. After 20 days of administration, MMO could significantly decrease prostate index and the levels of IL-10, TNF-α COX-2 and PGE2 in serum and could improve the prostate morphology in comparison with the model group. In summary, these results suggest that MMO possesses protective effects on prostate, which might be beneficial to further development for the treatment of CNP.


Assuntos
Gleiquênias , Extratos Vegetais/uso terapêutico , Prostatite/tratamento farmacológico , Animais , Doença Crônica , Masculino , Fitoterapia , Ratos , Ratos Sprague-Dawley , Rizoma
15.
Front Neurol ; 15: 1398827, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38887388

RESUMO

Introduction: Metaraminol is a sympathomimetic amine vasopressor that can be administrated through a peripheral venous access. However, limited evidence restricts its application in critically ill patients. This study aimed to investigate the safety and efficacy of peripheral metaraminol infusion in patients with neurological conditions. Methods: Patients who received peripheral metaraminol infusion between May 2019 and April 2022 were recruited. Data on baseline characteristics, clinical parameters, and infusion-related complications were retrospectively collected and analyzed. Results: 273 patients who received metaraminol were enrolled. Of these, 35 (12.8%) patients required central venous catheter insertion due to inability in achieving hemodynamic stability following peripheral metaraminol monotherapy. In 29,574.2 hours of vasopressor infusion, metaraminol infusion resulted achievement of the target blood pressure 73.4% of the time. Meanwhile, adverse events occurred in 5 patients and resolved after local tissue treatment. Discussion: Metaraminol could provide hemodynamic support and avoid complications associated with a central venous catheter and delay in vasopressor administration. Through careful and close monitoring, peripheral metaraminol infusion is safe and feasible for patients with neurological conditions. Future large-scale, prospective, multicenter studies are needed to evaluate the safety and efficacy of metaraminol infusion through a peripheral intravenous catheter.

16.
Org Lett ; 26(21): 4427-4432, 2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38757832

RESUMO

2,3-Diaryl propanoic acids are important structures as a result of their widespread presence in numerous bioactive compounds. However, the limitations of existing synthetic techniques include the requirement for costly catalysts and limited substrates. Here, we developed a novel electroreductive arylcarboxylation of alkenes with CO2 based on a radical-polar crossover pathway assisted by easily accessible dimethyl terephthalate as a reductive mediator. This method will provide an efficient strategy for the synthesis of 2,3-diarylpropanoic acids.

17.
Org Lett ; 26(21): 4526-4531, 2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38761124

RESUMO

We report a novel organic photoredox catalysis to achieve unprecedented γ-(hetero)aryl/alkenyl-δ-silyl aliphatic amines via silyl-mediated distal (hetero)aryl/alkenyl migration of aromatic/alkenyl amines bearing unactivated alkenes with hydrosilanes. This protocol features mild and metal-free reaction conditions, high atom economy, excellent selectivity, and functional group compatibility. Mechanistic studies suggest that silylation and (hetero)aryl/alkenylation involve photoredox hydrogen atom transfer catalysis and subsequent 1,4-migration of a remote (hetero)aryl/alkenyl group from nitrogen to carbon.

18.
Analyst ; 138(4): 1004-7, 2013 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-23301242

RESUMO

The first "off-on" dual-output fluorescent assay based on reaction-promoted self-assembly approach for glutathione recognition in near infrared region over other relative thiols including cysteine and homocysteine was constructed with high selectivity and large Stocks shift (about 220 nm). The fluorescence enhancement is attributed to the intermolecular interaction, which manipulates the squaraine's aggregates and results in FRET for NIR emission. The sensitivity of the sensing ensemble was further improved in buffer solution containing cationic surfactant.


Assuntos
Ciclobutanos/química , Transferência Ressonante de Energia de Fluorescência/métodos , Glutationa/análise , Fenóis/química , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Corantes Fluorescentes/química , Glutationa/química
19.
Biomed Eng Online ; 12: 6, 2013 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-23339544

RESUMO

BACKGROUND: Ultrasonography is a convenient technique to investigate muscle properties and has been widely used to look into muscle functions since it is non-invasive and real-time. Muscle thickness, a quantification which can effectively reflect the muscle activities during muscle contraction, is an important measure for musculoskeletal studies using ultrasonography. The traditional manual operation to read muscle thickness is subjective and time-consuming, therefore a number of studies have focused on the automatic estimation of muscle fascicle orientation and muscle thickness, to which the speckle noises in ultrasound images could be the major obstacle. There have been two popular methods proposed to enhance the hyperechoic regions over the speckles in ultrasonography, namely Gabor Filtering and Multiscale Vessel Enhancement Filtering (MVEF). METHODS: A study on gastrocnemius muscle is conducted to quantitatively evaluate whether and how these two methods could help the automatic estimation of the muscle thickness based on Revoting Hough Transform (RVHT). The muscle thickness results obtained from each of the two methods are compared with the results from manual measurement, respectively. Data from an aged subject with cerebral infarction is also studied. RESULTS: It's shown in the experiments that, Gabor Filtering and MVEF can both enable RVHT to generate comparable results of muscle thickness to those by manual drawing (mean ± SD, 1.45 ± 0.48 and 1.38 ± 0.56 mm respectively). However, the MVEF method requires much less computation than Gabor Filtering. CONCLUSIONS: Both methods, as preprocessing procedure can enable RVHT the automatic estimation of muscle thickness and MVEF is believed to be a better choice for real-time applications.


Assuntos
Interpretação de Imagem Assistida por Computador/métodos , Músculo Esquelético/diagnóstico por imagem , Adulto , Idoso , Índice de Massa Corporal , Peso Corporal , Infarto Cerebral/fisiopatologia , Simulação por Computador , Bases de Dados Factuais , Humanos , Masculino , Contração Muscular/fisiologia , Músculo Esquelético/fisiopatologia , Ultrassonografia
20.
Int J Mol Sci ; 14(9): 18850-60, 2013 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-24036444

RESUMO

A series of diaryl amines, ethers and thioethers were synthesized under microwave irradiation efficiently at presence of KF/Al2O3 in 83%-96% yields without any solvent. The salient characters of this method lie in short reaction time, high yields, general applicability to substrates and simple workup procedure. At the same time, their antifungal biological activities against six phytopathogen were evaluated. Most of the compounds (3b, 3c, 3g-o) are more potent than thiophannate-methyl against to Magnaporthe oryzae. This implies that diaryl amine or ether moiety may be helpful in finding a fungicide against Magnaporthe oryzae.


Assuntos
Aminas/síntese química , Aminas/farmacologia , Antifúngicos/síntese química , Antifúngicos/farmacologia , Éteres/síntese química , Éteres/farmacologia , Micro-Ondas , Solventes/química , Aminas/química , Antifúngicos/química , Éteres/química , Magnaporthe/efeitos dos fármacos
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