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1.
Apoptosis ; 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38652339

RESUMO

Chronic inflammatory and immune responses play key roles in the development and progression of chronic obstructive pulmonary disease (COPD). PANoptosis, as a unique inflammatory cell death modality, is involved in the pathogenesis of many inflammatory diseases. We aim to identify critical PANoptosis-related biomarkers and explore their potential effects on respiratory tract diseases and immune infiltration landscapes in COPD. Total microarray data consisting of peripheral blood and lung tissue datasets associated with COPD were obtained from the GEO database. PANoptosis-associated genes in COPD were identified by intersecting differentially expressed genes (DEGs) with genes involved in pyroptosis, apoptosis, and necroptosis after normalizing and removing the batch effect. Furthermore, GO, KEGG, PPI network, WGCNA, LASSO-COX, and ROC curves analysis were conducted to screen and verify hub genes, and the correlation between PYCARD and infiltrated immune cells was analyzed. The effect of PYCARD on respiratory tract diseases and the potential small-molecule agents for the treatment of COPD were identified. PYCARD expression was verified in the lung tissue of CS/LPS-induced COPD mice. PYCARD was a critical PANoptosis-related gene in all COPD patients. PYCARD was positively related to NOD-like receptor signaling pathway and promoted immune cell infiltration. Moreover, PYCARD was significantly activated in COPD mice mainly by targeting PANoptosis. PANoptosis-related gene PYCARD is a potential biomarker for COPD diagnosis and treatment.

2.
Gastric Cancer ; 27(2): 343-354, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38095766

RESUMO

OBJECTIVE: Patients with gastric atrophy and intestinal metaplasia (IM) were at risk for gastric cancer, necessitating an accurate risk assessment. We aimed to establish and validate a diagnostic approach for gastric biopsy specimens using deep learning and OLGA/OLGIM for individual gastric cancer risk classification. METHODS: In this study, we prospectively enrolled 545 patients suspected of atrophic gastritis during endoscopy from 13 tertiary hospitals between December 22, 2017, to September 25, 2020, with a total of 2725 whole-slide images (WSIs). Patients were randomly divided into a training set (n = 349), an internal validation set (n = 87), and an external validation set (n = 109). Sixty patients from the external validation set were randomly selected and divided into two groups for an observer study, one with the assistance of algorithm results and the other without. We proposed a semi-supervised deep learning algorithm to diagnose and grade IM and atrophy, and we compared it with the assessments of 10 pathologists. The model's performance was evaluated based on the area under the curve (AUC), sensitivity, specificity, and weighted kappa value. RESULTS: The algorithm, named GasMIL, was established and demonstrated encouraging performance in diagnosing IM (AUC 0.884, 95% CI 0.862-0.902) and atrophy (AUC 0.877, 95% CI 0.855-0.897) in the external test set. In the observer study, GasMIL achieved an 80% sensitivity, 85% specificity, a weighted kappa value of 0.61, and an AUC of 0.953, surpassing the performance of all ten pathologists in diagnosing atrophy. Among the 10 pathologists, GasMIL's AUC ranked second in OLGA (0.729, 95% CI 0.625-0.833) and fifth in OLGIM (0.792, 95% CI 0.688-0.896). With the assistance of GasMIL, pathologists demonstrated improved AUC (p = 0.013), sensitivity (p = 0.014), and weighted kappa (p = 0.016) in diagnosing IM, and improved specificity (p = 0.007) in diagnosing atrophy compared to pathologists working alone. CONCLUSION: GasMIL shows the best overall performance in diagnosing IM and atrophy when compared to pathologists, significantly enhancing their diagnostic capabilities.


Assuntos
Aprendizado Profundo , Gastrite Atrófica , Neoplasias Gástricas , Humanos , Gastrite Atrófica/diagnóstico , Gastrite Atrófica/patologia , Neoplasias Gástricas/diagnóstico , Neoplasias Gástricas/patologia , Gastroscopia/métodos , Biópsia/métodos , Fatores de Risco , Atrofia , Metaplasia/diagnóstico por imagem
3.
Int J Mol Sci ; 25(4)2024 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-38397120

RESUMO

Diamide insecticides have always been a hot research topic in the field of pesticides. To further discover new compounds with high activity and safety, indane and its analogs were introduced into chlorantraniliprole, and a battery of chlorfenil derivatives, including indane and its analogs, were designed and prepared for biological testing. Their characterization and verification were carried out through nuclear magnetic resonance (NMR) and high-resolution mass spectrometry (HRMS). Biological detection showed that all the compounds exhibited good insecticidal activity against Mythimna separata. At 0.8 mg/L, the insecticidal activity of compound 8q against Mythimna separata was 80%, which was slightly better than that of chlorantraniliprole. The results of the structure-activity relationship (SAR) analysis indicated that the indane moiety had a significant effect on insecticidal activity, especially in the R-configuration. The results indicated that chlorantraniliprole derivatives containing indane groups could serve as pilot compounds for the further development of new insecticides.


Assuntos
Inseticidas , Mariposas , ortoaminobenzoatos , Animais , Inseticidas/química , Diamida/farmacologia , Desenho de Fármacos , Relação Estrutura-Atividade , Estrutura Molecular
4.
Eur Radiol ; 33(7): 5159-5171, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36700956

RESUMO

OBJECTIVES: To evaluate amide proton transfer-weighted (APTw)-derived whole-tumor histogram analysis parameters in predicting pathological extramural venous invasion (pEMVI) positive status of rectal adenocarcinoma (RA). METHODS: Preoperative MR including APTw imaging of 125 patients with RA (mean 61.4 ± 11.6 years) were retrospectively analyzed. Two radiologists reviewed each case's EMVI status based on the MR-based modified 5-point scale system with conventional MR images. The APTw histogram parameters of primary tumors were obtained automatically using whole-tumor volume histogram analysis. The independent risk factors markedly correlated with pEMVI-positive status were assessed using univariate and multivariate logistic regression analyses. Diagnosis performance was assessed by receiver operating characteristic curve (ROC) analysis. The AUCs were compared using the Delong method. RESULTS: Univariate analysis demonstrated that MR-tumor (T) stage, MR-lymph node (N) stage, APTw-10%, APTw-90%, interquartile range, APTw-minimum, APTw-maximum, APTw-mean, APTw-median, entropy, kurtosis, mean absolute deviation (MAD), and robust MAD were significantly related to pEMVI-positive status (all p < 0.05). Multivariate analysis demonstrated that MR-T stage (OR = 4.864, p = 0.018), MR-N stage (OR = 4.967, p = 0.029), interquartile range (OR = 0.892, p = 0.037), APT-minimum (OR = 1.046, p = 0.031), entropy (OR = 11.604, p = 0.006), and kurtosis (OR = 1.505, p = 0.007) were the independent risk factors enabling prediction of pEMVI-positive status. The AUCs for diagnostic ability of conventional MRI assessment, the APTw histogram model, and the combined model (including APTw histogram and clinical variables) were 0.785, 0.853, and 0.918, respectively. The combined model outperformed the APTw histogram model (p = 0.013) and the conventional MRI assessment (p = 0.006). CONCLUSIONS: Whole-tumor histogram analysis of APTw images combined with clinical factors showed better diagnosis efficiency in predicting EMVI involvement in RA. KEY POINTS: • Rectal adenocarcinomas with pEMVI-positive status are typically associated with higher APTw-SI values. • APTw-minimum, interquartile range, entropy, kurtosis, MR-T stage, and MR-N stage are the independent risk factors for EMVI involvement. • The best prediction for EMVI involvement was obtained with a combined model of APTw histogram and clinical variables (area under the curve, 0.918).


Assuntos
Adenocarcinoma , Neoplasias Retais , Humanos , Prótons , Amidas , Carga Tumoral , Estudos Retrospectivos , Imageamento por Ressonância Magnética/métodos , Neoplasias Retais/diagnóstico por imagem , Neoplasias Retais/patologia , Adenocarcinoma/diagnóstico por imagem , Adenocarcinoma/patologia
5.
Molecules ; 28(4)2023 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-36838555

RESUMO

The increase in the insecticide resistance of pests, such as Mythimna separata, Aphis craccivora Koch, and Tetranychus cinnabarinus, necessitates the development of new heterocyclic compounds with high insecticidal activity. A series of novel 2-phenylpyridine derivatives containing N-phenylbenzamide moieties were designed and synthesised with Suzuki-Miyaura cross-coupling, nucleophilic substitution, and amidation reactions. The reaction conditions in each step are mild, and the product is easy to separate (yield is about 85%). The structures of the compounds were characterised using 1H and 13C NMR spectroscopy and HRMS. Moreover, the insecticidal activity of the compounds was analysed using the leaf dipping method. The compounds 5a, 5d, 5g, 5h, and 5k at 500 mg/L exhibited 100% inhibition against Mythimna separata. Therefore, the 2-phenylpyridine moieties have the potential to lead to the discovery of novel and effective insecticides.


Assuntos
Afídeos , Inseticidas , Mariposas , Tetranychidae , Animais , Inseticidas/química , Piridinas/farmacologia , Estrutura Molecular , Relação Estrutura-Atividade
6.
Can J Infect Dis Med Microbiol ; 2023: 9933783, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37663453

RESUMO

Beauveria bassiana is a well-known insecticidal biocontrol agent. Despite its broad field applications, its survival, colonization, and stability under field conditions remained unclear, mainly due to the lack of a quick and reliable detection method. In this study, we developed a quantitative real-time PCR technology to monitor the stability and population dynamics of B. bassiana in different substrates (water, soil, and on the cotton leaves surface), different spores of B. bassiana applied on Chinese cabbage leaves surface, and the lethality of Pieris rapae spraying with different spores of B. bassiana. Our results showed a decreased concentration of B. bassiana DNA in all three substrates from the 1st day till 9th day of post inoculation (dpi) period, possibly due to the death of B. bassiana. After this decrease, a quick and significant rebound of B. bassiana DNA concentration was observed, starting from the 11th dpi in all three substrates. The B. bassiana DNA concentration reached the plateau at about 13th dpi in water and 17th dpi in the soil. On cotton leaves surface, the B. bassiana DNA concentration reached the highest level at the 17th dpi followed by a small decline and then stabilized. This increase of DNA concentration suggested recovery of B. bassiana growth in all three substrates. We found that the most suitable killing effectiveness of P. rapae was the 1.0 × 107 spores/mL of B. bassiana. In summary, we have established a detection technology that allows a fast and reliable monitoring for the concentration and stability of B. bassiana under different conditions. This technology can benefit and help us in the development of proper management strategies for the application of this biocontrol agent in the field.

7.
Int J Mol Sci ; 23(19)2022 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-36232394

RESUMO

To find novel herbicidal compounds with high activity and broad spectrum, a series of phenylpyridine moiety-containing α-trifluoroanisole derivatives were designed, synthesized, and identified via nuclear magnetic resonance (NMR) and high-resolution mass spectrometry (HRMS). Greenhouse-based herbicidal activity assays revealed that compound 7a exhibited > 80% inhibitory activity against Abutilon theophrasti, Amaranthus retroflexus, Eclipta prostrate, Digitaria sanguinalis, and Setaria viridis at a dose of 37.5 g a.i./hm2, which was better than fomesafen. Compound 7a further exhibited excellent herbicidal activity against Abutilon theophrasti and Amaranthus retroflexus in this greenhouse setting, with respective median effective dose (ED50) values of 13.32 and 5.48 g a.i./hm2, both of which were slightly superior to fomesafen (ED50 = 36.39, 10.09 g a.i./hm2). The respective half-maximal inhibitory concentration (IC50) for compound 7a and fomesafen when used to inhibit the Nicotiana tabacum protoporphyrinogen oxidase (NtPPO) enzyme, were 9.4 and 110.5 nM. The docking result of compound 7a indicated that the introduction of 3-chloro-5-trifluoromethylpyridine and the trifluoromethoxy group was beneficial to the formation of stable interactions between these compounds and NtPPO. This work demonstrated that compound 7a could be further optimized as a PPO herbicide candidate to control various weeds.


Assuntos
Amaranthus , Herbicidas , Benzamidas/farmacologia , Herbicidas/química , Herbicidas/farmacologia , Plantas Daninhas , Protoporfirinogênio Oxidase/química , Relação Estrutura-Atividade , Nicotiana
8.
Molecules ; 27(19)2022 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-36234814

RESUMO

To discover new compounds with favorable herbicidal activity, a range of phenylpyridine moiety-containing pyrazole derivatives were designed, synthesized, and identified via NMR and HRMS. Their herbicidal activities against six species of weeds were evaluated in a greenhouse via both pre- and post-emergence treatments at 150 g a.i./hm2. The bioassay revealed that a few compounds exhibited moderate herbicidal activities against Digitaria sanguinalis, Abutilon theophrasti, and Setaria viridis in post-emergence treatment. For instance, compounds 6a and 6c demonstrated 50% inhibition activity against Setaria viridis, which was slightly superior to pyroxasulfone. Thus, compounds 6a and 6c may serve as the new possible leading compounds for the discovery of post-emergence herbicides.


Assuntos
Herbicidas , Digitaria , Herbicidas/química , Plantas Daninhas , Pirazóis/química , Pirazóis/farmacologia , Relação Estrutura-Atividade
9.
Molecules ; 27(18)2022 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-36144624

RESUMO

To discover novel herbicidal compounds with favorable activity, a range of phenylpyridine-moiety-containing α-trifluorothioanisole derivatives were designed, synthesized, and identified via NMR and HRMS. Preliminary screening of greenhouse-based herbicidal activity revealed that compound 5a exhibited >85% inhibitory activity against broadleaf weeds Amaranthus retroflexus, Abutilon theophrasti, and Eclipta prostrate at 37.5 g a.i./hm2, which was slightly superior to that of fomesafen. The current study suggests that compound 5a could be further optimized as an herbicide candidate to control various broadleaf weeds.


Assuntos
Amaranthus , Herbicidas , Herbicidas/química , Plantas Daninhas , Relação Estrutura-Atividade
10.
Phytopathology ; 111(3): 500-508, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32876530

RESUMO

G-negative bacteria produce myriad N-acyl-homoserine lactones (AHLs) that can function as quorum sensing (QS) signaling molecules. AHLs are also known to regulate various plant biological activities. p-Coumaroyl-homoserine lactone (pC-HSL) is the only QS molecule produced by a photosynthetic bacterium, Rhodopseudomonas palustris. The role of pC-HSL in the interaction between R. palustris and plant has not been investigated. In this study, we investigated the effect of pC-HSL on plant immunity and found that this QS molecule can induce a systemic resistance to Tobacco mosaic virus (TMV) infection in Nicotiana benthamiana. The results show that pC-HSL treatment can prolong the activation of two mitogen-associated protein kinase genes (i.e., NbSIPK and NbWIPK) and increase the expression of transcription factor WRKY8 as well as immune response marker genes NbPR1 and NbPR10, leading to an increased accumulation of reactive oxygen species (ROS) in the TMV-infected plants. Our results also show that pC-HSL treatment can increase activities of two ROS-scavenging enzymes, peroxidase and superoxide dismutase. Knockdown of NbSIPK or NbWIPK expression in N. benthamiana plants through virus-induced gene silencing nullified or attenuated pC-HSL-induced systemic resistance, indicating that the functioning of pC-HSL relies on the activity of those two kinases. Meanwhile, pC-HSL-pretreated plants also showed a strong induction of kinase activities of NbSIPK and NbWIPK after TMV inoculation. Taken together, our results demonstrate that pC-HSL treatment increases plant resistance to TMV infection, which is helpful to uncover the outcome of interaction between R. palustris and its host plants.


Assuntos
Percepção de Quorum , Vírus do Mosaico do Tabaco , 4-Butirolactona/análogos & derivados , Doenças das Plantas , Rodopseudomonas , Nicotiana , Regulação para Cima
11.
Molecules ; 26(13)2021 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-34202103

RESUMO

Eight novel pyridyl-oxazole carboxamides were evaluated against fungi and displayed good fungicidal activities against Botrytis cinereal and Rhizoctonia solani. Preliminary bioassay results indicated that at 100 mg/L, compounds 6a-6e, 6g and 6h exhibited 100% fungicidal activities against Botrytis cinerea, and the compound 6b to Rhizoctonia solani at 100%. Then, the zebrafish embryo acute toxicity test was performed to assess the toxicity of 6b and 6c. A series of malformations appeared, when the zebrafish embryos were exposed to 6b and 6c, such as delayed yolk sac resorption, significant shortening of body length, pericardial edema, bending spine, lack of melanin, heart hemorrhage, head hemorrhage, delayed swim sac development, yolk malformation and head malformation. In addition, the acute toxicity of 6b to zebrafish embryo is 4.878 mg/L, and 6c is 6.257 mg/L.


Assuntos
Antifúngicos , Botrytis/crescimento & desenvolvimento , Embrião não Mamífero/embriologia , Imidazóis , Rhizoctonia/crescimento & desenvolvimento , Peixe-Zebra/embriologia , Animais , Antifúngicos/efeitos adversos , Antifúngicos/química , Antifúngicos/farmacologia , Imidazóis/efeitos adversos , Imidazóis/química , Imidazóis/farmacologia
12.
Int J Mol Sci ; 21(23)2020 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-33260627

RESUMO

Squamosa promoter binding protein (SBP)-box genes are plant-specific transcription factors involved in plant growth and development, morphogenesis and biotic and abiotic stress responses. However, these genes have been understudied in pepper, especially with respect to defense responses to Phytophthora capsici infection. CaSBP11 is a SBP-box family gene in pepper that was identified in our previous research. Silencing CaSBP11 enhanced the defense response of pepper plants to Phytophthora capsici. Without treatment, the expression of defense-related genes (CaBPR1, CaPO1, CaSAR8.2 and CaDEF1) increased in CaSBP11-silenced plants. However, the expression levels of these genes were inhibited under transient CaSBP11 expression. CaSBP11 overexpression in transgenic Nicotiana benthamiana decreased defense responses, while in Arabidopsis, it induced or inhibited the expression of genes in the salicylic acid and jasmonic acid signaling pathways. CaSBP11 overexpression in sid2-2 mutants induced AtNPR1, AtNPR3, AtNPR4, AtPAD4, AtEDS1, AtEDS5, AtMPK4 and AtNDR1 expression, while AtSARD1 and AtTGA6 expression was inhibited. CaSBP11 overexpression in coi1-21 and coi1-22 mutants, respectively, inhibited AtPDF1.2 expression and induced AtPR1 expression. These results indicate CaSBP11 has a negative regulatory effect on defense responses to Phytophthora capsici. Moreover, it may participate in the defense response of pepper to Phytophthora capsici by regulating defense-related genes and the salicylic and jasmonic acid-mediated disease resistance signaling pathways.


Assuntos
Capsicum/imunologia , Regulação da Expressão Gênica de Plantas , Phytophthora/fisiologia , Doenças das Plantas/genética , Doenças das Plantas/imunologia , Proteínas de Plantas/metabolismo , Arabidopsis/genética , Capsicum/genética , Núcleo Celular/metabolismo , Ciclopentanos/metabolismo , Resistência à Doença/genética , Inativação Gênica , Modelos Biológicos , Mutação/genética , Oxilipinas/metabolismo , Fenótipo , Doenças das Plantas/microbiologia , Plantas Geneticamente Modificadas , Transporte Proteico , Transdução de Sinais , Nicotiana/genética , Nicotiana/microbiologia
13.
Molecules ; 25(15)2020 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-32722453

RESUMO

A series of novel phenyl methoxyacrylate derivatives containing a 2-alkenylthiopyrimidine substructure were designed, synthesized, and evaluated in terms of acaricidal activity. The structures of the title compounds were identified by 1H NMR, 13C NMR and high-resolution mass spectra (HRMS). Compound (E)-methyl 2-(2-((2-(3,3-dichloroallylthio)-6-(trifluoromethyl)pyrimidin-4-yloxy)methyl)phenyl)-3-methoxyacr-ylate (4j) exhibited significant acaricidal activity against Tetranychus cinnabarinus (T. cinnabarinus) in greenhouse tests possessing nearly twice the larvicidal and ovicidal activity compared to fluacrypyrim. Furthermore, the results of the field trials demonstrated that compound 4j could effectively control Panonychuscitri with long-lasting persistence and rapid action. The toxicology data in terms of LD50 value confirmed that compound 4j has a relatively low acute toxicity to mammals, birds, and honeybees.


Assuntos
Acaricidas/química , Inseticidas/química , Pirimidinas/química , Tetranychidae/efeitos dos fármacos , Acaricidas/síntese química , Acrilatos/síntese química , Acrilatos/química , Acrilatos/farmacologia , Animais , Inseticidas/síntese química , Inseticidas/farmacologia , Larva/efeitos dos fármacos , Larva/patogenicidade , Estrutura Molecular , Pirimidinas/síntese química , Pirimidinas/farmacologia , Tetranychidae/patogenicidade
14.
Phytother Res ; 33(3): 602-609, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30637903

RESUMO

The principal active component of isoforskolin (ISOF) is from the plant Coleus forskohlii, native to China, which has attracted much attention for its biological effects. We hypothesize that ISOF and forskolin (FSK) pretreatment attenuates inflammation induced by lipopolysaccharide (LPS) related to toll-like receptor 4 (TLR4), myeloid differentiation factor 88 (MyD88), and nuclear factor kappa B (NF-κB) signaling. Mononuclear leukocytes (MLs) from healthy donors' blood samples were separated by using density gradient centrifugation. Protein levels of TLR4, MyD88, and NF-κB were detected using western blot and inflammatory cytokines interleukin (IL) 1ß, IL-2, IL-6, IL-21, IL-23, tumor necrosis factor (TNF) α, and TNF-ß were tested by enzyme-linked immunosorbent assay and Quantibody array in MLs. Our results showed that LPS augmented the protein levels of TLR4, MyD88, and NF-κB in MLs and the production of IL-1ß, IL-2, IL-6, IL-21, IL-23, TNF-α, and TNF-ß in supernatants of MLs. Despite treatment with ISOF and FSK prior to LPS, the protein levels of TLR4, MyD88, NF-κB, IL-1ß, IL-2, IL-6, IL-21, IL-23, TNF-α, and TNF-ß in MLs were apparently decreased. roflumilast (RF) and dexamethasone (DM) had a similar effect on MLs with ISOF and FSK. Our results, for the first time, have shown that ISOF and FSK attenuate inflammation in MLs induced by LPS through down-regulating protein levels of IL-1ß and TNF-α, in which TLR4/MyD88/NF-κB signal pathway could be involved.


Assuntos
Colforsina/farmacologia , Inflamação/tratamento farmacológico , Leucócitos Mononucleares/efeitos dos fármacos , Fator 88 de Diferenciação Mieloide/fisiologia , NF-kappa B/fisiologia , Transdução de Sinais/efeitos dos fármacos , Receptor 4 Toll-Like/fisiologia , Citocinas/análise , Humanos , Leucócitos Mononucleares/metabolismo , Lipopolissacarídeos/toxicidade
15.
Org Biomol Chem ; 15(19): 4191-4198, 2017 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-28443921

RESUMO

A highly enantioselective conjugate addition of 2-substituted benzofuran-3(2H)-ones to α,ß-unsaturated ketones promoted by chiral copper complexes has been developed, affording the Michael addition products with quaternary stereocenters in good to high yields (up to 95% yield) with excellent enantioselectivities (up to 99% ee). The chiral Michael adducts could be readily converted to the polycyclic benzofuran-type framework via the Robinson annulation.

16.
Org Biomol Chem ; 15(27): 5709-5718, 2017 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-28650044

RESUMO

An asymmetric formal one-pot reaction of 4-hydroxycoumarins with unsaturated pyrazolones has been developed by merging a chiral bifunctional organocatalyst with molecular iodine, which furnished a series of optically active spiro[dihydrofurocoumarin/pyrazolone] heterocycles with spiro quaternary stereogenic centers in moderate to excellent yields (up to 99%) with excellent diastereoselectivities (up to >99 : 1 dr) and good to excellent enantioselectivities (up to 99% ee). The application in the gram-scale synthesis of chiral spiro[dihydrofurocoumarin/pyrazolone] compounds was also successfully realized.


Assuntos
Furocumarinas/síntese química , Pirazolonas/síntese química , Compostos de Espiro/síntese química , Ciclização , Furocumarinas/química , Estrutura Molecular , Pirazolonas/química , Compostos de Espiro/química
17.
Org Biomol Chem ; 13(25): 7084-90, 2015 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-26052796

RESUMO

A facile synthetic route towards pharmaceutically interesting ß-keto-sulfone derivatives by tetrabutylammonium iodide (TBAI)/tert-butyl hydroperoxide (TBHP) mediated oxidative coupling of readily prepared enamides with economical sulfonylhydrazides is described. The corresponding ß-keto-sulfone compounds were obtained in moderate to good yields. The present method is metal-free and base-free and shows tolerance to a variety of functional groups.


Assuntos
Amidas/química , Hidrazinas/química , Cetonas/síntese química , Acoplamento Oxidativo , Compostos de Amônio Quaternário/química , Sulfonas/síntese química , Amidas/síntese química , Catálise , Hidrazinas/síntese química , Iodetos/química , Cetonas/química , Ácidos Sulfínicos/síntese química , Ácidos Sulfínicos/química , Sulfonas/química , terc-Butil Hidroperóxido/química
18.
BMC Plant Biol ; 14: 138, 2014 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-24885401

RESUMO

BACKGROUND: The pepper fruit is the second most consumed vegetable worldwide. However, low temperature affects the vegetative development and reproduction of the pepper, resulting in economic losses. To identify cold-related genes regulated by abscisic acid (ABA) in pepper seedlings, cDNA representational difference analysis was previously performed using a suppression subtractive hybridization method. One of the genes cloned from the subtraction was homologous to Solanum tuberosum MBF1 (StMBF1) encoding the coactivator multiprotein bridging factor 1. Here, we have characterized this StMBF1 homolog (named CaMBF1) from Capsicum annuum and investigated its role in abiotic stress tolerance. RESULTS: Tissue expression profile analysis using quantitative RT-PCR showed that CaMBF1 was expressed in all tested tissues, and high-level expression was detected in the flowers and seeds. The expression of CaMBF1 in pepper seedlings was dramatically suppressed by exogenously supplied salicylic acid, high salt, osmotic and heavy metal stresses. Constitutive overexpression of CaMBF1 in Arabidopsis aggravated the visible symptoms of leaf damage and the electrolyte leakage of cell damage caused by cold stress in seedlings. Furthermore, the expression of RD29A, ERD15, KIN1, and RD22 in the transgenic plants was lower than that in the wild-type plants. On the other hand, seed germination, cotyledon greening and lateral root formation were more severely influenced by salt stress in transgenic lines compared with wild-type plants, indicating that CaMBF1-overexpressing Arabidopsis plants were hypersensitive to salt stress. CONCLUSIONS: Overexpression of CaMBF1 in Arabidopsis displayed reduced tolerance to cold and high salt stress during seed germination and post-germination stages. CaMBF1 transgenic Arabidopsis may reduce stress tolerance by downregulating stress-responsive genes to aggravate the leaf damage caused by cold stress. CaMBF1 may be useful for genetic engineering of novel pepper cultivars in the future.


Assuntos
Adaptação Fisiológica , Arabidopsis/genética , Arabidopsis/fisiologia , Capsicum/metabolismo , Proteínas de Plantas/metabolismo , Estresse Fisiológico , Adaptação Fisiológica/efeitos dos fármacos , Sequência de Aminoácidos , Arabidopsis/efeitos dos fármacos , Arabidopsis/crescimento & desenvolvimento , Capsicum/genética , Temperatura Baixa , DNA Complementar/genética , DNA Complementar/isolamento & purificação , Eletrólitos , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Proteínas de Choque Térmico/metabolismo , Dados de Sequência Molecular , Fenótipo , Proteínas de Plantas/química , Plantas Geneticamente Modificadas , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ácido Salicílico/farmacologia , Plântula/efeitos dos fármacos , Plântula/genética , Alinhamento de Sequência , Análise de Sequência de DNA , Cloreto de Sódio/farmacologia , Estresse Fisiológico/efeitos dos fármacos , Estresse Fisiológico/genética
19.
J Org Chem ; 79(1): 446-51, 2014 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-24328134

RESUMO

A novel arylalkoxycarbonylation of N-aryl acrylamides with carbazates leading to alkoxycarbonylated oxindoles has been developed. The reported reactions employ economical and environmentally benign FeCl2·4H2O as a catalyst and easily accessible and safe carbazates as alkoxycarbonyl radical precursors.


Assuntos
Acrilamidas/química , Hidrazinas/química , Indóis/química , Ferro/química , Catálise , Estrutura Molecular
20.
Chem Commun (Camb) ; 2024 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-38984732

RESUMO

A photoinduced EnT-mediated generation of sulfonamidyl radicals has been accomplished using rationally designed iminophenylacetic acid oxime ester reagents under metal-free conditions. This approach offers a mild, regio- and diastereoselective synthesis of N-sulfonyl diamines via diamination of alkenes and (hetero)arenes.

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