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1.
Molecules ; 27(15)2022 Aug 04.
Artículo en Inglés | MEDLINE | ID: mdl-35956916

RESUMEN

Herein, we first report an electrochemical methodology for the site-selective alkylation of azobenzenes with (thio)xanthenes in the absence of any transition metal catalyst or external oxidant. A variety of groups are compatible with this electrochemical alkylation, which furnishes the products in moderate to good yields.


Asunto(s)
Compuestos Azo , Xantenos , Alquilación , Catálisis
2.
Int J Clin Pract ; 2022: 3840882, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35685561

RESUMEN

Objectives: This cross-sectional study aimed to evaluate the associations among orthodontic history, psychological status, and temporomandibular-related quality of life. Methods: A questionnaire was developed and distributed to students in a local college, containing questions about demographic information, the Patient Health Questionnaire-4 (PHQ-4), the Fonseca anamnestic index, and the Oral Health Impact Profile for Temporomandibular Disorders (OHIP-TMD). The respondents were divided into with orthodontic history (OS) group and without OS group. Binary logistic regression and multiple linear regression were performed for statistical analysis. Results: A total of 531 valid questionnaires were collected, covering 161 participants with OS and 370 participants without OS. No statistically significant differences were observed in the scores of PHQ-4 between the two groups. There was statistical difference in the prevalence of TMD (with OS group, 54.66%; without OS group, 40.81%) and the mean value ( ± standard deviations) of the scores of OHIP-TMD (with OS group, 9.64 ± 12.36; without OS group, 6.64 ± 10.79) (p < 0.05). After adjusting confounding factors, participants with OS have worse temporomandibular-related quality of life and a higher risk of having TMD than the participants without OS. Conclusions: Orthodontic history was related with the higher prevalence of TMD and worse temporomandibular-related quality of life, but not related with psychological distress, and the cause-and-effect relationship needs further exploration.


Asunto(s)
Calidad de Vida , Trastornos de la Articulación Temporomandibular , Estudios Transversales , Humanos , Salud Bucal , Encuestas y Cuestionarios , Trastornos de la Articulación Temporomandibular/epidemiología , Trastornos de la Articulación Temporomandibular/psicología
3.
J Org Chem ; 87(2): 1056-1064, 2022 Jan 21.
Artículo en Inglés | MEDLINE | ID: mdl-34964353

RESUMEN

An electrochemical cross-dehydrogenative coupling of indoles with xanthenes has been established at room temperature. This coupling reaction could proceed in the absence of any catalyst or external oxidant, and generate the indole derivatives in moderate yields. Mechanistic experiments support that a radical pathway maybe involved in this reaction system.

4.
Org Lett ; 23(21): 8204-8208, 2021 Nov 05.
Artículo en Inglés | MEDLINE | ID: mdl-34676767

RESUMEN

A novel and efficient method for the selective synthesis of sulfinylated benzofulvenes has been developed through the BF3·Et2O-promoted electrophilic addition/cyclization of 1,3-enynes. This metal-free cascade reaction employs readily accessible arylsulfinic acids as sulfinyl cation sources at room temperature and provides a wide range of functionalized benzofulvenes in good to excellent yields under mild conditions.

5.
Org Lett ; 23(15): 5698-5702, 2021 08 06.
Artículo en Inglés | MEDLINE | ID: mdl-34264080

RESUMEN

A novel and effective method for the synthesis of spirolactones from readily available α-keto acids and 1,3-enynes is developed via a BF3·Et2O-promoted cascade annulation. This sequential process is conducted at room temperature, and it provides the functionalized spirolactones in good to excellent yield under metal-free conditions.

6.
J Org Chem ; 85(21): 13808-13817, 2020 Nov 06.
Artículo en Inglés | MEDLINE | ID: mdl-33063514

RESUMEN

A novel and efficient visible-light-induced decarboxylative cyclization/hydrogenation cascade reaction of α-oxocarboxylic acids and 2-isocyanobiaryls has been developed. Without the need of any external photosensitizer, oxidant, and reductant, this method offers a mild and green approach for the synthesis of diverse alcohols in moderate to good yields. A mechanism indicated that an electron donor-acceptor complex-driven decarboxylation, radical addition/cyclization, and in situ photochemical reduction of ketones to alcohols could be involved in the reaction.

7.
Org Lett ; 21(23): 9291-9295, 2019 12 06.
Artículo en Inglés | MEDLINE | ID: mdl-31710495

RESUMEN

A novel copper-catalyzed cascade reaction of arylsulfonylhydrazones derived from ortho-alkynyl arylketones was accomplished. This reaction provides concise access to diversified cinnolines in good yields. The mechanistic investigations have disclosed involvement of the key alkynyl amination, 1,4-aryl migration, desulfonylation, and diazo radical cyclization cascade in the transformation.

8.
Int Immunopharmacol ; 74: 105705, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-31228814

RESUMEN

OBJECTIVE: Surgical site infection (SSI) is a common complication in patients following posterior lumbar spinal surgery. Various laboratory data such as laboratory parameters derived neutrophil/lymphocyte count ratio (NLR), have been applied for the prediction of SSI, but more studies are necessary to evaluate the significance of these indicators. Here, our study aims to investigate the predictive value of total white blood cells (WBCs), count and percentages of neutrophils and leukocytes, NLR, and C-reactive protein (CRP) for surgical site infection (SSI) in patients after posterior lumbar spinal surgery. METHODS: A total of 293 patients who underwent posterior lumbar spinal surgery were enrolled in this study. Each patient's medical history was retrospectively reviewed, and patients were divided into the deep SSI group (n = 13) and the non-SSI group (n = 280). Laboratory data including total WBC, count and percentages of neutrophils and leukocytes, NLR at 1 week before the operation and the 4 and 7 days post-operation, and CRP at 4 and 7 days post-operation were analysed between the SSI and non-SSI groups. Moreover, predictive power and cut-off of NLR for SSI were determined by receiver operating characteristic curve (ROC) results. RESULTS: Data revealed that the medians of NLR were markedly increased in the SSI group as compared to that in non-SSI group at 4 days (p = 0.011) and 7 days (p = 0.047) post-operation. Moreover, the neutrophil percentage was also dramatically increased in the SSI group at both 4 and 7 days post-operation (p = 0.010 and p = 0.030) respectively compared to the non-SSI group. However, no significant difference was observed between the groups 1 week before the operation. ROC results showed that NLR at 4 days (cut-off >5.19; sensitivity: 61.5%; specificity: 77.6%; AUC = 0.708) and 7 days (cut-off >3.85; sensitivity: 69.2%; specificity: 62.7%; AUC = 0.663) post-operation could significantly discriminate the SSI and non-SSI groups. Logistic regression analysis showed that NLR at both post-operative time points (OR = 1.218; p = 0.003 and OR = 1.296; p = 0.048) could be valuable predictors for SSI. CONCLUSION: NLR at 4 and 7 days post-operation are valuable laboratory predictors for SSI in patients with posterior lumbar spinal surgery.


Asunto(s)
Laminectomía/efectos adversos , Recuento de Leucocitos/métodos , Linfocitos/patología , Neutrófilos/patología , Estenosis Espinal/diagnóstico , Infección de la Herida Quirúrgica/diagnóstico , Adulto , Anciano , Proteína C-Reactiva/metabolismo , Femenino , Humanos , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Pronóstico , Estenosis Espinal/cirugía
9.
Org Lett ; 21(1): 124-128, 2019 01 04.
Artículo en Inglés | MEDLINE | ID: mdl-30576157

RESUMEN

A novel and efficient strategy for the direct synthesis of benzo[ f]indazoles via copper-catalyzed cascade reaction of sulfonyl hydrazides with 1,3-enynes under mild conditions has been developed. This method achieves the formation of two C-N bonds and one C-C bond in one pot, providing a series of benzo[ f]indazoles in moderate to good yields with good functional group tolerance and remarkable regioselectivity.

10.
Org Biomol Chem ; 17(1): 115-121, 2018 12 19.
Artículo en Inglés | MEDLINE | ID: mdl-30520913

RESUMEN

An effective protocol of photoredox catalyzed C2-alkylation of benzothiazoles with aliphatic carboxylic acids was disclosed. In the presence of an acridinium salt as a photocatalyst and air as an oxidant, a wide range of secondary or tertiary aliphatic carboxylic acids were employed as alkylation reagents, providing the desired products in good to excellent yields under mild reaction conditions with a broad substrate scope.

11.
Org Lett ; 20(15): 4416-4420, 2018 08 03.
Artículo en Inglés | MEDLINE | ID: mdl-30004706

RESUMEN

A novel and efficient method for selective synthesis of diaryl sulfoxides and m-arylthio sulfones has been achieved from readily available arylsulfinic acids and arenes via an unusual sulfinyl cation, providing a range of structurally diverse products in good to excellent yields under mild conditions. Notably, mechanistic investigations suggested m-arylthio sulfones were generated from diaryl sulfoxides and sulfinyl cation by a sequence of redox reaction and electrophilic aromatic substitution process.

12.
Org Lett ; 20(7): 1735-1739, 2018 04 06.
Artículo en Inglés | MEDLINE | ID: mdl-29527899

RESUMEN

A novel and efficient photoinduced synthesis of C6-polyfunctionalized phenanthridines from three-component reactions of isocyanides, alkynes and sulfinic acids was developed. The reactions generated the corresponding products with high selectivity through the photochemical activity of the formed electron donor-acceptor (EDA) complex during the reaction via a radical tandem process under mild conditions.

13.
Chem Commun (Camb) ; 52(77): 11559-62, 2016 Oct 04.
Artículo en Inglés | MEDLINE | ID: mdl-27604055

RESUMEN

A novel synthesis of sulfonated dihydroisoquinolinones via cascade radical addition and cyclization was developed in the presence of tert-butyl hydroperoxide (TBHP). The reactions generated the desired sulfonated dihydroisoquinolinones in good yields from readily available arylsulfinic acids and N-allylbenzamides under metal-free conditions.

14.
Chem Commun (Camb) ; 52(15): 3175-8, 2016 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-26805487

RESUMEN

The oxidative difunctionalization of aryl alkynoates via benzyl radical initiated intramolecular 1,4-aryl migration and decarboxylation tandem process was developed in the presence of tert-butyl hydroperoxide as an oxidant, which provides a direct and selective route to a variety of trisubstituted alkenes from simple toluene derivatives and aryl alkynoates.

15.
Chem Asian J ; 10(9): 1919-25, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26097076

RESUMEN

A novel photocatalytic synthesis of sulfonated oxindoles from N-arylacrylamides and arylsulfinic acids was developed by means of a cascade C-S/C-C bond-formation process. This method provides mild, efficient, and atom-economical access to various sulfonated oxindoles in water.

16.
Org Lett ; 17(4): 832-5, 2015 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-25643239

RESUMEN

A novel and efficient electrophilic sulfenylation of indoles with arylsulfinic acids is realized. The reaction utilizes readily available starting materials in water under catalyst- and additive-free conditions, providing an alternative and attractive approach to 3-arylsulfinylindoles with high yields. Preliminary mechanistic investigation suggested that the reaction is through an electrophilic substitution process.


Asunto(s)
Indoles/síntesis química , Ácidos Sulfínicos/química , Catálisis , Técnicas Químicas Combinatorias , Estructura Molecular , Agua
17.
Chem Asian J ; 9(9): 2584-9, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24920177

RESUMEN

A novel and efficient palladium-catalyzed C2 arylation of N-substituted indoles with 1-aryltriazenes for the synthesis of 2-arylindoles was developed. In the presence of BF3⋅OEt2 and palladium(II) acetate (Pd(OAc)2), N-substituted indoles reacted with 1-aryltriazenes in N,N-dimethylacetamide (DMAC) to afford the corresponding aryl-indole-type products in good to excellent yields.


Asunto(s)
Indoles/química , Indoles/síntesis química , Compuestos Organometálicos/química , Paladio/química , Triazenos/química , Catálisis , Estructura Molecular
18.
Chem Asian J ; 8(12): 3185-90, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24000204

RESUMEN

The rapid and efficient direct C2-arylation of free (NH)-indoles with arylsulfinic acids proceeded through a microwave-accelerated palladium-catalyzed desulfitation reaction. By using PdCl2 as a catalyst, silver acetate as an oxidant, and H2SO4 as an additive, arylsulfinic acids with both electron-donating and electron-withdrawing groups underwent desulfitative coupling with an array of free (NH)-indoles, thereby selectively providing C2-arylindoles in good yields.


Asunto(s)
Indoles/química , Indoles/síntesis química , Microondas , Paladio/química , Ácidos Sulfínicos/química , Catálisis , Estructura Molecular
19.
Org Biomol Chem ; 11(11): 1867-73, 2013 Mar 21.
Artículo en Inglés | MEDLINE | ID: mdl-23381643

RESUMEN

An efficient and direct use of formamides as amino group sources for the synthesis of α-ketoamides was developed under metal-free conditions. The reaction was based on the oxidative coupling of acetophenones with formamides and generated the desired products in good yields in the presence of t-BuOOH/I(2)/PhCO(2)H.


Asunto(s)
Acetofenonas/química , Amidas/síntesis química , Formamidas/química , Cetonas/síntesis química , Amidas/química , Catálisis , Yodo/química , Cetonas/química , Estructura Molecular , Oxidación-Reducción , terc-Butilhidroperóxido/química
20.
Org Biomol Chem ; 11(3): 420-4, 2013 Jan 21.
Artículo en Inglés | MEDLINE | ID: mdl-23207659

RESUMEN

An efficient tandem elimination-cyclization-desulfitative arylation of 2-(gem-dibromovinyl)phenols(thiophenols) with sodium arylsulfinates has been developed. In the presence of TBAF-PdCl(2)-Cu(OAc)(2)-NEt(3), the reactions generated 2-arylbenzofurans(thiophenes) with good yields in one-pot under ligand-free conditions.


Asunto(s)
Arilsulfonatos/química , Benzofuranos/síntesis química , Fenoles/química , Sodio/química , Tiofenos/síntesis química , Compuestos de Vinilo/química , Benzofuranos/química , Ciclización , Estructura Molecular , Tiofenos/química
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