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1.
Chemistry ; : e202304234, 2024 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-38644695

RESUMO

With both TEMPO and O2 (in air) as the homogeneous redox mediators, BiBrO as the heterogeneous semiconductor photocatalyst, the first example of semi-heterogeneous photocatalytic decarboxylative phosphorylation of N-arylglycines with diarylphosphine oxides was established. A series of α-amino phosphinoxides were efficiently synthesized.

2.
J Org Chem ; 89(13): 9543-9550, 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38874168

RESUMO

A visible-light-initiated C-H trifluoromethylation of quinoxalin-2(1H)-ones was established using a Z-scheme V2O5/g-C3N4 heterojunction as a recyclable photocatalyst in an inert atmosphere at room temperature under additive-free and mild conditions. A variety of trifluoromethylated quinoxalin-2-(1H)-one derivatives were heterogeneously generated in moderate to high yields, exhibiting good functional group tolerance. Remarkably, the recyclable V2O5/g-C3N4 catalyst could be reused five times with a slight loss of catalytic activity.

3.
J Org Chem ; 89(6): 4113-4119, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38448366

RESUMO

The first example of an electrochemical multicomponent synthesis of selenium-containing compounds with inexpensive and abundant elemental selenium as the selenating reagent was developed. A variety of selenazol-2-amines were constructed in high yields with good functional group tolerance under metal-free and chemical oxidant-free conditions.

4.
J Org Chem ; 89(9): 6117-6125, 2024 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-38654588

RESUMO

The first paired electrolysis-enabled arylation of quinoxalin-2(1H)-ones was achieved using cyanoarenes as the arylation reagents. A variety of 3-arylquinoxalin-2(1H)-ones with various important functional groups were obtained in moderate to good yields under metal- and chemical oxidant-free conditions. With a pair of reductive and oxidative processes occurring among the substrates and reaction intermediates, the power consumption can be dramatically reduced.

5.
J Org Chem ; 88(4): 2288-2295, 2023 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-36738288

RESUMO

A simple and practical electron donor-acceptor (EDA) strategy to synthesize various 3-alkylated coumarins from easily available coumarins and naturally abundant carboxylic acids under photocatalyst-, oxidant-, and additive-free and mild conditions is reported. Using Na2S as the catalytic electron donor, a series of primary, secondary, and tertiary carbon radicals can be efficiently generated, and the EDA complex can be regenerated without an alkaline additive.

6.
J Org Chem ; 88(13): 8360-8368, 2023 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-37262353

RESUMO

A 1,2,3,5-tetrakis(carbazol-9-yl)-4,6-dicyanobenzene (4-CzIPN)-photocatalyzed cascade arylation/cyclization reaction of 2-isocyanobiaryls and iodonium ylides was established for the synthesis of 6-arylated phenanthridines. This is the first example of employing iodonium ylides as aryl radical sources in a visible-light-induced radical cascade cyclization reaction.


Assuntos
Luz , Fenantridinas , Ciclização
7.
J Org Chem ; 88(24): 16790-16796, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-38016176

RESUMO

A general and efficient method for the synthesis of various selanyl phenanthrenes/polycyclic heteroaromatics through the electrophilic annulation of 2-alkynyl biaryls with diorganyl diselenides under metal-free and mild conditions was established. The sulfanyl phenanthrene was also obtained in moderate yields.

8.
Org Biomol Chem ; 21(2): 370-374, 2023 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-36515252

RESUMO

A concise and efficient ring-opening difluorination strategy was developed for the synthesis of highly functionalized hydroxy-containing α,α-difluoro-ß-ketoamides from the one-pot multicomponent reaction of 4-aminocoumarins, NFSI, and water in dimethyl carbonate (DMC) as a green solvent. The reactions were smoothly achieved under visible light irradiation in air at room temperature without the addition of any other external photocatalysts. With this protocol, various α,α-difluoro-ß-ketoamides were successfully synthesized under mild conditions (25 examples, 73-91% yields). This transition-metal-free synthetic procedure shows good functional group compatibility and attractive practical potential for large-scale synthesis.


Assuntos
Amidas , Luz , Solventes
9.
Graefes Arch Clin Exp Ophthalmol ; 261(1): 223-231, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36029306

RESUMO

BACKGROUND: SFTs are thought to have an unpredictable clinical course and currently have no recognized prognostic criterion. Our study aimed to determine the relationship between clinicopathological characteristics and the prognosis of patients with orbital SFTs. METHODS: The clinicopathological features of these patients were extracted from clinical records. The relationships between these features and prognosis were analysed. RESULTS: The positive rates of CD34, CD99, Blc2, and STAT6 expression were 90.3%, 90.3%, 83.9%, and 100%, respectively. The tumour recurrence rate was 38.7%. A higher recurrence rate was observed in patients with Ki67 index ≥ 5 (56.25% vs. 20%, P = 0.038). CONCLUSION: A Ki67 index ≥ 5 was an effective parameter for predicting tumour recurrence of orbital SFTs. Close follow-up is needed for these patients.


Assuntos
Hemangiopericitoma , Febre Grave com Síndrome de Trombocitopenia , Tumores Fibrosos Solitários , Humanos , Antígeno Ki-67 , Recidiva Local de Neoplasia/epidemiologia , Recidiva Local de Neoplasia/patologia , Tumores Fibrosos Solitários/diagnóstico , Tumores Fibrosos Solitários/cirurgia , Tumores Fibrosos Solitários/metabolismo , Hemangiopericitoma/patologia , Biomarcadores Tumorais
10.
Molecules ; 28(3)2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36771059

RESUMO

The first example of paired electrolysis-enabled cyanation of diaryl diselenides, with KSCN as the green cyanating agent, has been developed. A broad range of aryl selenocyanates can be efficiently synthesized under chemical-oxidant- and additive-free, energy-saving and mild conditions.

11.
Org Biomol Chem ; 20(43): 8501-8505, 2022 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-36268850

RESUMO

The first example of the electrocatalytic multicomponent synthesis of 4-chloro/bromo/iodopyrazoles from hydrazines, acetylacetones and sodium halides under chemical oxidant- and external electrolyte-free conditions has been developed. Sodium halides played a dual role as a halogenation reagent and a supporting electrolyte. Mechanism studies revealed that the bromination reaction proceeded via an ionic pathway, whereas both chlorination and iodination proceeded via a radical pathway.


Assuntos
Halogênios , Sódio , Halogenação , Oxidantes , Íons
12.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 52(3): 510-515, 2021 May.
Artigo em Zh | MEDLINE | ID: mdl-34018373

RESUMO

OBJECTIVE: To explore the clinical features of thyroid-associated ophthalmopathy (TAO) with extraocular muscle involvement. METHODS: The data of 2170 TAO patients who were seen at the Orbital Disease Clinic, West China Hospital, Sichuan University from September, 2009 to January, 2020 were collected retrospectively. The extraocular muscle involvement of these patients was confirmed by CT or MRI. Their general condition, medical history, clinical manifestations and imaging features were analyzed retrospectively. RESULTS: Among the 2170 TAO patients, 932 were male and 1238 were female. The mean (± SD) age of all the patients was (46.95±13.06) years, ranging between 6 and 85. 1684 patients (77.60%) suffered from hyperthyroidism, 13 patients (0.59%) had thyroid cancer, 80 patients (3.69%) had hypothyroidism, and 393 patients (18.11%) had normal thyroid function. Proptosis (55.25%) and diplopia (33.09%) were the main reasons for their visits to the clinic, and restricted eye movements (83.46%) was the most common sign. 122 patients with a mean age of (53.24±13.07) years did not show any eyelid sign and had only extraocular muscle involvement. The 2170 TAO patients had a total of 3799 eyes of extrocular muscle involvement, with 541 patients experiencing monocular involvement and 1629 patients, binocular involvement; 1204 eyes (31.69%) had a single extrocular muscle involved and 2595 eyes (68.31%) had multiple extrocular muscles involved. Inferior rectus was the most commonly involved muscle, followed by superior rectus, medial rectus, and lateral rectus in descending order of involvement frequency. Of the 1014 patients who underwent enhanced MRI, 71.99% were shown to be in the active phase. 69.03% of the 775 patients identified as being in inactive phase according to their clinical activity score (CAS) were shown to be in the active phase according to their MRI results. CONCLUSION: TAO patients with extraocular muscle involvement have their own specific clinical manifestations. CT and MRI can both be used to assist in the diagnosis of extraocular muscle involvement. MRI can be used to assess the pathological stage of extraocular muscles and is more sensitive than CAS.


Assuntos
Oftalmopatia de Graves , Adulto , Idoso , China , Feminino , Oftalmopatia de Graves/diagnóstico por imagem , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Músculos Oculomotores/diagnóstico por imagem , Estudos Retrospectivos
13.
Org Biomol Chem ; 18(27): 5234-5237, 2020 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-32602499

RESUMO

A novel Cu(i)-catalyzed intermolecular cyanoarylation of alkenes with diaryliodonium salts as a radical arylating reagent and tetra-butylammonium cyanide as an electrophilic cyanating reagent was established. A broad range of α-alkylated arylacetonitriles were efficiently constructed in good to excellent yields under base- and oxidant-free and mild conditions.

14.
J Org Chem ; 84(10): 6065-6071, 2019 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-30999750

RESUMO

A general and efficient protocol for the direct preparation of various S-thiocarbamates with readily available and inexpensive sulfonyl chlorides as an odorless sulfur source was developed. The employment of easily available reactants, excellent functional group tolerability, and mild reaction conditions make this process very practical.

15.
Org Biomol Chem ; 16(46): 9064-9068, 2018 11 28.
Artigo em Inglês | MEDLINE | ID: mdl-30456395

RESUMO

A simple and practical method for the synthesis of alkenyl dithiocyanates and alkenyl diselenocyanates has been developed via stereoselective difunctionalization of alkynes with NaSCN or KSeCN at room temperature. Through this methodology, a series of alkenyl dithiocyanates and alkenyl diselenocyanates could be efficiently and conveniently obtained in moderate to good yields under mild and metal-free conditions by the simple use of oxone and PhI(OAc)2 as the oxidants.

16.
Org Biomol Chem ; 16(37): 8403-8407, 2018 09 26.
Artigo em Inglês | MEDLINE | ID: mdl-30215086

RESUMO

A simple and practical molecular iodine-mediated method for the efficient construction of thiocarbamates from isocyanides, thiols and water under metal-free and mild conditions has been developed. A variety of thiocarbamates were easily synthesized through this methodology, which has the advantages of simple operation, eco-friendly conditions, good functional group tolerance, and readily accessible raw materials.

17.
Org Biomol Chem ; 16(27): 5050-5054, 2018 07 11.
Artigo em Inglês | MEDLINE | ID: mdl-29956708

RESUMO

A simple palladium-catalyzed selective synthesis of structurally diverse 3,4-dihydroquinazolines from electron-rich arylamines, electron-poor arylamines and glyoxalates has been developed under mild conditions. This reaction is carried out in a tandem manner constituted by the condensation of arylamines and glyoxalates, the selective Diels-Alder cycloaddition and oxidation processes, in which 4-nitrothiophenol was used as the key ligand.

18.
Org Biomol Chem ; 16(17): 3177-3180, 2018 05 02.
Artigo em Inglês | MEDLINE | ID: mdl-29645051

RESUMO

A convenient and efficient indium-catalyzed approach to synthesize alkenyl iodides has been developed through direct iodoalkylation of alkynes with alcohols and aqueous HI under mild conditions. This catalytic protocol offers an attractive approach for the synthesis of a diverse range of alkenyl iodides in good to excellent yields.

19.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 48(5): 727-731, 2017 Sep.
Artigo em Zh | MEDLINE | ID: mdl-29130665

RESUMO

OBJECTIVE: To explore the effects of insulin-like growth factor1 (IGF1) receptor (IGF1R) on the synthesis of hyaluronic acid (HA) in orbital fibroblasts of thyroid associated ophthalmopathy (TAO) and its signal pathway. METHODS: Orbital fibroblasts were harvested from TAO ( n=19) and normal control ( n=5),then were primary cultured and treated with recombinant human IGF1 in different concentrations. Before the treatment of IGF1,the cells were pretreated respectively with 1H7,LY294002 or AKT inhibitor Ⅳ for 24 h. The production of HA was measured using a commercial ELISA kit,and the synthesis of PI3K,Akt and pAkt was measured by Western blot. RESULTS: Along with the increase of recombinant human IGF1 concentration,the synthesis of HA by TAO orbital fibroblasts were increased as well,the synthesis of HA peaked at the concentration of 10 nmol/L in IGF1 in TAO group ( P<0.01). Compared with the normal control,orbital fibroblasts from TAO had the synthesis of HA increased after the treatment of IGF1 ( P<0.01). The pretreatment of 1H7 or AKT inhibitor Ⅳ significantly decreased the HA concentration in culture media ( P<0.01),while the decrease of HA synthesis in the group pretreated with LY294002 was not statistically significant ( P=0.390). IGF1 treatment increased the level of pAkt expression,but it seems no effects on PI3K and Akt expression. 1H7 and LY294002 decreased the expression of PI3K and pAkt protein,but no obvious inhibitory effect on total Akt protein. Akt inhibitor Ⅳ decreased the expression of PI3K,Akt and pAkt. CONCLUSION: The synthesis of HA by orbital fibroblasts could be increased in TAO,which may partially via phosphoinositide 3kinase/Akt pathway.


Assuntos
Fibroblastos/metabolismo , Oftalmopatia de Graves/metabolismo , Ácido Hialurônico/biossíntese , Órbita/citologia , Receptores de Somatomedina/metabolismo , Células Cultivadas , Cromonas/farmacologia , Humanos , Morfolinas/farmacologia , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Receptor IGF Tipo 1 , Proteínas Recombinantes/farmacologia , Transdução de Sinais
20.
J Biol Chem ; 290(24): 14875-83, 2015 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-25922079

RESUMO

Obesity and metabolic disorders such as insulin resistance and type 2 diabetes have become a major threat to public health globally. The mechanisms that lead to insulin resistance in type 2 diabetes have not been well understood. In this study, we show that mice deficient in MAPK phosphatase 5 (MKP5) develop insulin resistance spontaneously at an early stage of life and glucose intolerance at a later age. Increased macrophage infiltration in white adipose tissue of young MKP5-deficient mice correlates with the development of insulin resistance. Glucose intolerance in MKP5-deficient mice is accompanied by significantly increased visceral adipose weight, reduced AKT activation, enhanced p38 activity, and increased inflammation in visceral adipose tissue when compared with wild-type (WT) mice. Deficiency of MKP5 resulted in increased inflammatory activation in macrophages. These findings thus demonstrate that MKP5 critically controls inflammation in white adipose tissue and the development of metabolic disorders.


Assuntos
Tecido Adiposo/patologia , Inflamação/enzimologia , Resistência à Insulina , Fosfatases da Proteína Quinase Ativada por Mitógeno/metabolismo , Tecido Adiposo/enzimologia , Animais , Glucose/metabolismo , Macrófagos/patologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Fosfatases da Proteína Quinase Ativada por Mitógeno/genética
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