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1.
Mol Carcinog ; 63(7): 1288-1302, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38607237

RESUMO

Baicalein has been implicated in the chemotherapy overcoming triple-negative breast cancer (TNBC). However, many unanswered questions remain regarding its role in treating TNBC. Here, we sought to demonstrate the molecular pathway mediated by baicalein in TNBC. Lysine-specific demethylase 4E (KDM4E), reduced in TNBC cells, was identified as a target protein of baicalein, and baicalein enhanced the protein expression and stability of KDM4E in TNBC cells. Knockdown of KDM4E attenuated the inhibitory effect of baicalein on TNBC cell activity, as demonstrated by intensified mobility, viability, and apoptosis resistance in TNBC cells. KDM4E activated protein bicaudal D homolog 1 (BICD1) expression by reducing the deposition of histone H3 lysine 9 trimethylation (H3K9me3) in its promoter, whereas BICD1 promoted protease-activated receptor-1 (PAR1) endocytosis and blocked PAR1 signaling through physical interaction with PAR1. Knockdown of KDM4E strengthened the PAR1-dependent activity of TNBC cells in response to thrombin activation, whereas TNBC progression activated by PAR1 signaling was blocked by combined overexpression of BICD1. Taken together, our data indicate that baicalein-promoted KDM4E enhanced the expression of BICD1 and activated the inhibitory effect of BICD1 on PAR1 signaling, thereby inhibiting TNBC progression.


Assuntos
Flavanonas , Transdução de Sinais , Neoplasias de Mama Triplo Negativas , Humanos , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Neoplasias de Mama Triplo Negativas/metabolismo , Neoplasias de Mama Triplo Negativas/patologia , Neoplasias de Mama Triplo Negativas/genética , Flavanonas/farmacologia , Feminino , Transdução de Sinais/efeitos dos fármacos , Linhagem Celular Tumoral , Animais , Receptor PAR-1/metabolismo , Receptor PAR-1/genética , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Apoptose/efeitos dos fármacos , Progressão da Doença , Camundongos
2.
J Environ Manage ; 358: 120847, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38626486

RESUMO

Platinum group metals (PGMs) are strategic metals. Auto-exhaust catalysts are their main application fields. The recovery of PGMs from spent auto-exhaust catalysts has remarkable economic value and strategic significance. Aiming at the problems of ferrosilicon generation for Fe capturing and subsequent oxygen blowing to remove iron with high energy consumption and heat release, a technology of Fe-Sn synergistic capturing PGMs was proposed. Taking full the advantage of the lower melting point of Fe-Sn alloy (<1200 °C) and its unique affinity for PGMs, the PGMs were captured at approximate 1400 °C with Fe-Sn as the collector. In experiment, 500 g of spent auto-exhaust catalysts were employed to minimize error and approximate industrial production. The mechanism of Fe-Sn synergistic capturing PGMs was elucidated. The generation of Fe-Sn-PGMs alloy lowered the activity of [PGMs] in the system, accelerated the reduction of the PGMs oxides and promoted the alloying of [PGMs]. Therefore, Fe-Sn synergistic capturing PGMs was realized. The inability of Si to enter the alloy phase was confirmed by theoretical calculations, avoiding the generation of ferrosilicon. The effects of basicity, CaF2, m(Fe)/m(Sn) and the amount of collector on capturing PGMs were optimized. Under the optimized conditions (basicity R = 1.1, spent auto-exhaust catalysts 70 wt%, CaO 30 wt%, B2O3 10 wt%, CaF2 7 wt%, m(Fe)/m(Sn) = 1/1 and the collector 15 wt%), the content of PGMs in the slag phase was 2.46 g/t. It is feasible to remove Fe and Sn by oxidation to achieve the purpose of PGMs enrichment. This technology offers guidance on the safe, environmentally sound, and efficient disposal of spent auto-exhaust catalysts, promoting the sustainable development of PGMs.


Assuntos
Ferro , Platina , Platina/química , Ferro/química , Catálise , Metais/química , Estanho/química , Ligas/química
3.
J Am Chem Soc ; 2023 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-36661845

RESUMO

The synthesis of structurally diverse amines is of fundamental significance in the pharmaceutical industry due to the ubiquitous presence of amine motifs in biologically active molecules. Biocatalytic reductive amination for amine production has attracted great interest owing to its synthetic advantages. Herein, we report the direct synthesis of a wide range of sterically demanding secondary amines, including several important active pharmaceutical ingredients and pharmaceutical intermediates, via reductive amination of carbonyl substrates and bulky amine nucleophiles employing imine reductases. Key to success for this route is the identification of an imine reductase from Penicillium camemberti with unusual substrate specificity and its further engineering, which empowered the accommodation of a broad range of sterically demanding amine nucleophiles encompassing linear alkyl and (hetero)aromatic (oxy)alkyl substituents and the formation of final amine products with up to >99% conversion. The practical utility of the biocatalytic route has been demonstrated by its application in the preparative synthesis of the anti-hyperparathyroidism drug cinacalcet.

4.
J Transl Med ; 21(1): 801, 2023 11 10.
Artigo em Inglês | MEDLINE | ID: mdl-37950289

RESUMO

BACKGROUND: Skin cutaneous melanoma (SKCM) is the most aggressive skin cancer, accounting for more than 75% mortality rate of skin-related cancers. As a newly identified programmed cell death, pyroptosis has been found to be closely associated with tumor progression. Nevertheless, the prognostic significance of pyroptosis in SKCM remains elusive. METHODS: A total of 469 SKCM samples and 812 normal samples were obtained from The Cancer Genome Atlas (TCGA) and Genotype-Tissue Expression (GTEx) databases. Firstly, differentially expressed pyroptosis-related genes (PRGs) between normal samples and SKCM samples were identified. Secondly, we established a prognostic model based on univariate Cox and LASSO Cox regression analyses, which was validated in the test cohort from GSE65904. Thirdly, a nomogram was used to predict the survival probability of SKCM patients. The R package "pRRophetic" was utilized to identify the drug sensitivity between the low- and high-risk groups. Tumor immune infiltration was evaluated using "immuneeconv" R package. Finally, the function of GSDMD and SB525334 was explored in A375 and A2058 cells. RESULTS: Based on univariate Cox and LASSO regression analyses, we established a prognostic model with identified eight PRGs (AIM2, CASP3, GSDMA, GSDMC, GSDMD, IL18, NLRP3, and NOD2), which was validated in the test cohort. SKCM patients were divided into low- and high-risk groups based on the median of risk score. Kaplan-Meier survival analysis showed that high-risk patients had shorter overall survival than low-risk patients. Additionally, time-dependent ROC curves validated the accuracy of the risk model in predicting the prognosis of SKCM. More importantly, 4 small molecular compounds (SB525334, SR8278, Gemcitabine, AT13387) were identified, which might be potential drugs for patients in different risk groups. Finally, overexpression of GSDMD and SB525334 treatment inhibit the proliferation, migration, and invasion of SKCM cells. CONCLUSION: In this study, we constructed a prognostic model based on PRGs and identified GSDMD as a potential therapeutic target, which provide new insights into SKCM treatment.


Assuntos
Melanoma , Neoplasias Cutâneas , Humanos , Melanoma/tratamento farmacológico , Melanoma/genética , Neoplasias Cutâneas/tratamento farmacológico , Neoplasias Cutâneas/genética , Piroptose/genética , Pele , Biomarcadores Tumorais/genética , Proteínas Citotóxicas Formadoras de Poros , Proteínas de Ligação a Fosfato/genética , Melanoma Maligno Cutâneo
5.
Chemistry ; 29(64): e202301796, 2023 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-37503795

RESUMO

A metal-free natural dye has been developed to selectively convert methane to methyl trifluoroacetate (CH3 TFA) using visible light, probably due to the formation of a chloride-bridged dimer undergoing fast intra-complex charge transfer.

6.
Ann Hematol ; 102(12): 3325-3333, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37787838

RESUMO

Epstein-Barr virus-associated hemophagocytic lymphohistiocytosis (EBV-HLH) is a severe hyperinflammatory illness that affects adults and is caused by an EBV infection. Without allogeneic hematopoietic stem cell transplantation (allo-HSCT), the overall survival of adult patients with EBV-HLH is unsatisfactory, necessitating the development of innovative therapeutic approaches. The clinical records of twelve EBV-HLH patients who received sintilimab therapy combined with ruxolitinib on a compassionate basis at the First Affiliated Hospital of Soochow University were retrospectively examined in this investigation. All the patients responded without fever, but three patients relapsed within a week. Among the nine patients achieving complete response (CR), 55.6% (5/9) maintained CR for >4.5 months, and 33.3% (3/9) relapsed following CR. Neither patients with no response (NR) nor relapsed patients were fit for allo-HSCT, and all died soon after discharge. Six patients had clinical CR with a median follow-up of 5 (4.4-14.7) months. There were no documented severe negative effects. Additional information on this innovative treatment for adult EBV-HLH is provided in our report.


Assuntos
Infecções por Vírus Epstein-Barr , Linfo-Histiocitose Hemofagocítica , Humanos , Adulto , Linfo-Histiocitose Hemofagocítica/complicações , Linfo-Histiocitose Hemofagocítica/tratamento farmacológico , Herpesvirus Humano 4 , Infecções por Vírus Epstein-Barr/complicações , Infecções por Vírus Epstein-Barr/tratamento farmacológico , Estudos Retrospectivos
7.
Am J Hematol ; 98(6): 881-889, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36880836

RESUMO

Conditioning therapy is an essential procedure prior to hematopoietic stem cell transplant (HSCT), imposing a great impact on the outcomes of recipients. We performed a prospective randomized controlled trial to assess the outcome of HSCT recipients with myeloid malignancies after receiving the conditioning therapy consisting of modified BUCY (mBUCY), N-acetyl-L-cysteine (NAC), and decitabine. Enrolled patients were randomly allocated to either Arm A (decitabine, day -12 to -10; NAC, day -9 to +30; mBUCY, day -9 to -2), or Arm B (mBUCY regimen followed by stem cells infusion). Seventy-six patients in Arm A and 78 patients in Arm B were finally evaluated. The results showed platelet recovery accelerate in Arm A, with more patients achieving a platelet count of ≥50 × 109 /L than Arm B at day +30 and +60 (p = .004 and .043, respectively). The cumulative incidence of relapse is 11.8% (95% CI 0.06-0.22) in Arm A, and 24.4% (95% CI 0.16-0.35) in Arm B (p = .048). The estimated 3-year overall survival rate was 86.4% (±4.4%) and 79.9% (±4.7%) in 2 arms, respectively (p = .155). EFS at 3 years was 79.2% (±4.9%) in Arm A and 60.0% (±5.9%) in Arm B (p = .007). Intracellular reactive oxygen species (ROS) level was found to be reversely correlated with platelet recovery, and fewer patients in Arm A displayed excessive ROS within hematopoietic progenitor cells compared to Arm B. In conclusion, the addition of decitabine and NAC to mBUCY is a feasible and promising conditioning therapy for myeloid malignancies patients.


Assuntos
Doença Enxerto-Hospedeiro , Transplante de Células-Tronco Hematopoéticas , Leucemia Mieloide Aguda , Transtornos Mieloproliferativos , Neoplasias , Humanos , Decitabina , Acetilcisteína/uso terapêutico , Bussulfano , Estudos Prospectivos , Espécies Reativas de Oxigênio , Transtornos Mieloproliferativos/complicações , Transplante de Células-Tronco Hematopoéticas/métodos , Terapia Comportamental , Neoplasias/complicações , Condicionamento Pré-Transplante/efeitos adversos , Leucemia Mieloide Aguda/terapia , Doença Enxerto-Hospedeiro/etiologia
8.
Inorg Chem ; 62(26): 10343-10350, 2023 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-37341569

RESUMO

Conversion of methane to liquid oxygenates is challenging but of great value. Here, we report the oxidation of methane (CH4) to methanol (CH3OH) assisted by nitrogen dioxide (NO2) as a photo-mediator and using molecular oxygen (O2) as the terminal oxidant. Similar photoreactions are widely studied in atmospheric chemistry but were not previously used in preparative methane conversion. We used visible light to excite NO2 generated by heating aluminum nitrate Al(NO3)3 and drove its reaction with methane and O2 to produce methyl nitrate (CH3ONO2), which is then hydrolyzed to CH3OH. Nitric acid (HNO3) and nitrate (NO3-) were produced and recycled back to Al(NO3)3, completing a chemical loop. HCl can catalyze this photochemical process via relay hydrogen atom-transfer reactions, with up to 17% methane conversion and 78% CH3ONO2 selectivity. This simple photochemical system provides new opportunities in selective methane transformation.

9.
Chem Biodivers ; 20(3): e202201129, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36862006

RESUMO

The phytochemical constituent investigation on the 70 % ethanol extract of the rhizomes of Tupistra chinensis Baker resulted in the isolation of three new steroidal saponins which were named tuchinosides A-C (1-3). Their structures were determined by extensive spectrum analysis and chemical evidence, especially 2D NMR and HR-ESI-MS techniques. In addition, the cytotoxicity of compounds 1-3 against several human cancer cell lines was evaluated.


Assuntos
Asparagaceae , Saponinas , Humanos , Saponinas/química , Rizoma/química , Linhagem Celular , Espectroscopia de Ressonância Magnética , Estrutura Molecular
10.
Int Wound J ; 20(10): 4300-4307, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37493021

RESUMO

By conducting a meta-analysis of relevant clinical studies on the treatment of advanced gastric cancer (GC) using laparoscopic and open surgeries, we aimed to evaluate the impact of these two surgical approaches on postoperative surgical site infections (SSIs) in patients with advanced GC. We aimed to provide evidence-based support for preventing SSIs in postoperative patients with advanced GC. From database establishment until May 2023, we systematically searched PubMed, Cochrane Library, MEDLINE, Embase, China National Knowledge Infrastructure, and Wanfang Data databases for relevant studies comparing laparoscopic and open surgeries for the treatment of advanced GC. Two researchers independently performed the literature screening and data extraction based on predefined inclusion and exclusion criteria. The meta-analysis was conducted using STATA 17.0. Twenty articles involving 3084 patients met the inclusion criteria, including 1462 patients in the laparoscopic group and 1622 cases in the open surgery group. The meta-analysis results revealed that the incidence of postoperative SSIs was significantly lower in the laparoscopic group than in the open surgery group (odds ratio = 0.341, 95% confidence interval: 0.219-0.532, p < 0.001). The current evidence indicates that laparoscopic radical gastrectomy can significantly reduce the incidence of postoperative site infections in patients with advanced GC.


Assuntos
Laparoscopia , Neoplasias Gástricas , Humanos , Infecção da Ferida Cirúrgica/etiologia , Infecção da Ferida Cirúrgica/prevenção & controle , Infecção da Ferida Cirúrgica/cirurgia , Neoplasias Gástricas/cirurgia , Gastrectomia/efeitos adversos , Gastrectomia/métodos , Laparoscopia/efeitos adversos , Laparoscopia/métodos , China/epidemiologia
11.
Org Biomol Chem ; 20(8): 1769-1781, 2022 02 23.
Artigo em Inglês | MEDLINE | ID: mdl-35166749

RESUMO

The three-component reaction between a protected α-amino aldehyde, an alcohol and an α-silyloxymalononitrile provides an expedient access to protected α-hydroxy-ß-amino acid derivatives. The prototypical process, performed on N-Cbz-phenylalaninal, is known to proceed with syn diastereoselectivity. The present study demonstrates that the diastereoselectivity of the reaction can be inverted, using the rationale of a Felkin-Anh interaction model. Reactions performed on N,N-dibenzyl-L-phenylalaninal proceed with a high anti diastereoselectivity, providing a panel of synthetically useful ester derivatives of (2S,3S)-allophenylnorstatin. The procedure is exploited to accomplish one of the most efficient syntheses of the title compound to date, in 3 steps (66% yield) from N,N-dibenzyl-L-phenylalaninal.

12.
BMC Pulm Med ; 22(1): 473, 2022 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-36510158

RESUMO

BACKGROUND: Pulmonary chronic graft-versus-host disease (cGVHD) after allogeneic hematopoietic stem cell transplantation (allo-HSCT) is a devastating complication and often diagnosed at a late stage when lung dysfunction is irreversible. Identifying patients before transplant who are at risk may offer improved strategies to decrease the mortality. Bronchiolitis obliterans syndrome (BOS) is the typical manifestation of pulmonary cGVHD, which is clinically diagnosed by pulmonary function test (PFT). This study aimed to evaluate the predictive value of PFT pre-HSCT for BOS. METHODS: A single center cohort of 923 allo-HSCT recipients was analyzed, including 15 patients who developed pulmonary cGVHD. Kaplan-Meier method was used to analyze the 3 year progression free survival and 3 year overall survival (OS). A Cox regression model was applied for univariate and multivariate models. RESULTS: The 3 year cumulative incidence of pulmonary cGVHD was 2.04% (95% CI 1.00-3.08%). According to the cut-off values determined by receiver operator characteristic curve, higher ratio of forced expiratory volume during one second to forced vital capacity (FEV1/FVC) pre-HSCT was correlated to a lower incidence of pulmonary cGVHD [0.91% (95% CI 0.01-1.81%) vs. 3.61% (95% CI 1.30-5.92%), P < 0.01], and so as peak expiratory flow to predictive value (PEF/pred) [0.72% (95% CI 0-1.54%) vs. 3.74% (95% CI 1.47-6.01%), P < 0.01]. Multivariate analysis showed that FEV1/FVC (HR = 3.383, P = 0.047) and PEF/pred (HR = 4.426, P = 0.027) were independent risk factors for onset of BOS. Higher FEV1/FVC and PEF/pred level were related to a significantly decreased 3 year non-relapse mortality. The 3 year OS was superior in patients with higher PEF/pred [78.17% (95% CI 74.50-81.84%) vs. 71.14% (95% CI 66.08-76.20%), P = 0.01], while FEV1/FVC did not show significance difference. CONCLUSION: Our results suggested that PFT parameters such as PEF/pred and FEV1/FVC could be predictors for pulmonary cGVHD and even transplant outcomes before HSCT.


Assuntos
Transplante de Células-Tronco Hematopoéticas , Humanos , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Pulmão , Testes de Função Respiratória , Volume Expiratório Forçado , Capacidade Vital , Estudos Retrospectivos
13.
J Dairy Sci ; 104(4): 4893-4903, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33551160

RESUMO

Streptococcus agalactiae is a contagious pathogen that causes bovine mastitis worldwide, resulting in considerable economic losses. In this study, we isolated 42 S. agalactiae strains in 379 milk samples from cows with subclinical mastitis on 15 dairy farms in 12 Chinese provinces. Analysis based on capsular typing and multilocus sequence typing, combined with patterns of virulence gene scanning and antimicrobial resistance, identified the lineages and populations of the isolates. We grouped the 42 isolates into 7 sequence types belonging to 6 clonal complexes, mainly CC103 (31/42 isolates; 73.8%). We identified an ST-23 strain named Sa 129 for the first time on Chinese dairy farms-this strain is usually associated with human isolates. Capsular types Ia and II were predominant in capsular typing. The prevalence of virulence profile 1 (bibA, cfb, cspA, cylE, fbsA, fbsB, hylB, and pavA) was 64.3%, and represented the main trend in China. With respect to antimicrobial resistance, most isolates were susceptible to ß-lactams, rifamycin, glycopeptides, and oxazolidone; resistance to several antimicrobial agents, including lincomycin, clindamycin, and doxycycline, varied in 4 different regions. Our research provides a profile for the molecular epidemiology, multilocus sequence typing, antimicrobial resistance, and virulence gene clustering of S. agalactiae, and may be beneficial for the clinical monitoring, prevention, and control of mastitis in dairy cattle.


Assuntos
Doenças dos Bovinos , Mastite Bovina , Mastite , Animais , Antibacterianos/farmacologia , Bovinos , China/epidemiologia , Análise por Conglomerados , Feminino , Mastite/veterinária , Mastite Bovina/epidemiologia , Epidemiologia Molecular , Tipagem de Sequências Multilocus , Streptococcus agalactiae/genética , Virulência/genética , Fatores de Virulência/genética
14.
J Am Chem Soc ; 142(1): 75-79, 2020 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-31840518

RESUMO

CO2 hydrogenation to ethanol is of practical importance but poses a significant challenge due to the need of forming one C-C bond while keeping one C-O bond intact. CuI centers could selectively catalyze CO2-to-ethanol conversion, but the CuI catalytic sites were unstable under reaction conditions. Here we report the use of low-intensity light to generate CuI species in the cavities of a metal-organic framework (MOF) for catalytic CO2 hydrogenation to ethanol. X-ray photoelectron and transient absorption spectroscopies indicate the generation of CuI species via single-electron transfer from photoexcited [Ru(bpy)3]2+-based ligands on the MOF to CuII centers in the cavities and from Cu0 centers to the photoexcited [Ru(bpy)3]2+-based ligands. Upon light activation, this Cu-Ru-MOF hybrid selectively hydrogenates CO2 to EtOH with an activity of 9650 µmol gCu-1 h-1 under 2 MPa of H2/CO2 = 3:1 at 150 °C. Low-intensity light thus generates and stabilizes CuI species for sustained EtOH production.

16.
Beilstein J Org Chem ; 16: 966-973, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32509027

RESUMO

Pd-catalyzed asymmetric Suzuki-Miyaura couplings of 3-methyl-2-bromophenylamides, 3-methyl-2-bromo-1-nitrobenzene and 1-naphthaleneboronic acids have been successfully developed and the corresponding axially chiral biaryl compounds were obtained in very high yields (up to 99%) with good enantioselectivities (up to 88% ee) under mild conditions. The chiral-bridged biphenyl monophosphine ligands developed by our group exhibit significant superiority to the naphthyl counterpart MOP in both reactivity and enantioselectivity control. The large steric hindrance from π-conjugated ortho-substituents of the bromobenzene substrates and the Pd···O interaction between carbonyl and palladium seem essential to achieve high enantioselectivity.

19.
Phytother Res ; 33(4): 1150-1160, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30768741

RESUMO

Acute hypobaric hypoxia (HH) gives rise to persistent cognitive impairment, influencing memory function specifically. Echinacoside (ECH), one of the phenylethanoids isolated from the stems of Cistanche salsa, has been reported to prevent ischemia induced by neuronal injury traditionally. This study then tried to investigate whether ECH could alleviate HH-induced memory deficit. Ten C57 mice were used as control, and 50 were exposed to HH equivalent to 6,100 m for 7 days in a decompression chamber and were given ECH daily (50, 75, or 100 mg/kg) through gavage during the period of exposure. Cognitive performance was evaluated by the Morris water maze test. ECH, especially at 100 mg/kg, significantly reduced HH-induced memory decline. Furthermore, ECH increased the expression of nuclear factor E2 p45-related factor 2, heme oxygenase-1, NAD(P)H:quinone oxidoreductase 1, and γ-glutamyl cysteine synthetase in mRNA and protein levels, suggesting that the Keap1-Nrf2-ARE signaling pathway might be involved in neuronal adaptation. The results indicate that ECH could prevent HH-induced memory impairment, which is associated with antioxidant effect of ECH in the hippocampus.


Assuntos
Glicosídeos/uso terapêutico , Transtornos da Memória/tratamento farmacológico , Fator 2 Relacionado a NF-E2/metabolismo , Animais , Hipóxia Celular , Glicosídeos/farmacologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL
20.
Org Biomol Chem ; 16(30): 5533-5538, 2018 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-30027977

RESUMO

Salicylic acids and substituted ynones were employed as substrates to afford a class of valuable 4H-benzo[d][1,3]dioxin-4-ones with a 2-site quaternary carbon structure in up to 92% yield by secondary amine-catalyzed dual Michael cascade reactions under mild reaction conditions. The α,ß-unsaturated ketone as the key intermediate in the cascade process was successfully separated and characterized. As a result, a new reaction route for ynone species is demonstrated, which is totally different from the existing allenamine activation model.

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