4,802 results on '"Naphthols"'
Search Results
102. Asymmetric Dearomative Halogenation of β‐Naphthols: The Axial Chirality Transfer Reaction.
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Wang, Pengxin, Wang, Jie, Wang, Linqing, Li, Dan, Wang, Kezhou, Liu, Yuyang, Zhu, Haiyong, Liu, Xihong, Yang, Dongxu, and Wang, Rui
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HALOGENATION , *NAPHTHOL , *CHIRALITY , *AROMATIZATION , *CHEMICAL yield , *CHEMICAL reactions - Abstract
Abstract: Axial naphthols are applied in asymmetric halogenative dearomatization reactions under simple and mild conditions in the work presented herein. The axial‐to‐central chirality conversion is efficiently accomplished, and the desired halogenated dearomatization products are obtained in high yields and enantioselectivities. By using commercially available halogenation reagents, the asymmetric fluorinative, chlorinative and brominative dearomatization reactions of axial naphthols derived from BINOLs are achieved. (BINOL=1,1′‐Bi‐2‐naphthol) [ABSTRACT FROM AUTHOR]
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- 2018
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103. NMR Study of the Discrimination of Enantiomers of Methamphetamine and Its Raw Materials Using Chiral Solvating Agents
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Motoo Iida and Ruri Kikura-Hanajiri
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Magnetic Resonance Spectroscopy ,Pharmaceutical Science ,Naphthols ,Methamphetamine ,chemistry.chemical_compound ,medicine ,Ephedrine ,Enantiomeric excess ,Phenylacetates ,Pharmacology ,Chloroform ,Trifluoromethyl ,Chromatography ,Illicit Drugs ,Stereoisomerism ,Pseudoephedrine ,chemistry ,Solvents ,Proton NMR ,Drug and Narcotic Control ,Enantiomer ,Ethers ,medicine.drug - Abstract
Some controlled substances, such as stimulants and narcotics, have asymmetric carbons in their molecules. Because the enantiomers do not always show the same pharmacological effects, and there are substances with different controls due to differences in their stereochemistry, a simple and unambiguous method for assessment of the composition of enantiomers is necessary. In this study, to develop a simple and rapid stereoscopic identification method for methamphetamine and its raw materials (ephedrine and pseudoephedrine), the 1H-NMR method was studied using three commercially available chiral solvating agents (CSAs); 1,1'-bi(2-naphthol)(BINOL), 2,2,2-trifluoro-1-(9-anthryl)ethanol (TFAE) and α-methoxy-α-(trifluoromethyl)phenylacetic acid (MTPA). In addition, the accuracy of the optical purity, which was measured using samples mixed with enantiomers in various ratios, was investigated. The NMR peaks of the enantiomers were separated by adding (R)- or (S)-form of BINOL, TFAE or MTPA to the chloroform-d solution of methamphetamine, ephedrine or pseudoephedrine. A sufficient discrimination of enantiomers was obtained by adding about 10 equal amounts of each CSA to the solutions. With regard to the optical purity, it was possible to determine accurately the mixing of small amounts of enantiomers of about 5% even if the NMR peaks did not reach the baseline separation, when impurity peaks do not overlap. This method will be one of the useful techniques for the rapid and simple discrimination of enantiomers of illegal methamphetamine and its raw materials.
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- 2021
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104. Highly Selective and Sensitive Benzimidazole Based Bifunctional Sensor for Targeting Inedible Azo Dyes in Red Chilli, Red Food Color, Turmeric Powder, and Cu(Ii) in Coconut Water
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Ifra Ilyas Ansari, Ambreen Abbasi, and Mohammad Shakir
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Cocos ,Sudan I ,Benzimidazole ,food.ingredient ,Sociology and Political Science ,Clinical Biochemistry ,ALIZARIN RED ,Naphthols ,Chili powder ,010402 general chemistry ,01 natural sciences ,Biochemistry ,chemistry.chemical_compound ,Curcuma ,food ,Bifunctional ,Spectroscopy ,010405 organic chemistry ,Highly selective ,Fluorescence ,0104 chemical sciences ,Clinical Psychology ,Food color ,chemistry ,Azo Compounds ,Law ,Social Sciences (miscellaneous) ,Nuclear chemistry - Abstract
In this study, a simple Benzimidazole based bifunctional chemosensor 4-(2-(3,4-dimethoxyphenyl)-1H-benzo[d]imidazol-6-yl) benzene-1,2-diamine, L was synthesized and characterized. The sensor proved to be selective and sensitive towards detecting banned azo dyes Sudan Dye I, II, and Metanil Yellow via fluorescence turn-off response. The proposed mechanism of fluorescence quenching was the inner filter effect. LODs for Sudan I, II, and Metanil Yellow were found to be 0.009 µM, 0.012 µM, and 0.0073 µM, respectively. The developed chemosensor also showed a colorimetric response towards Cu (II) ions via an apparent color change from yellow to pink. LOD for Cu (II) ions was found to be 1.2 µM. The synthesized benzimidazole based bifunctional chemosensor was adequately tested to determine Sudan I in Red chili powder and red Food color samples, Metanil yellow in turmeric powder, and Cu(II) packaged coconut water.
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- 2021
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105. Improved Plasmodium falciparum dilution cloning through efficient quantification of parasite numbers and c-SNARF detection
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Gerhard Wunderlich, Tatiane Macedo-Silva, and Sanjay A. Desai
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0301 basic medicine ,Microplate Well ,Plasmodium ,Dilution cloning ,Serial dilution ,ANIMAIS PARASITOS ,medicine.medical_treatment ,Plasmodium falciparum ,030231 tropical medicine ,RC955-962 ,Naphthols ,Infectious and parasitic diseases ,RC109-216 ,Flow cytometry ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Limiting dilution ,Arctic medicine. Tropical medicine ,medicine ,Parasite hosting ,Benzopyrans ,Cloning, Molecular ,Malaria, Falciparum ,medicine.diagnostic_test ,biology ,Rhodamines ,Methodology ,Flow Cytometry ,biology.organism_classification ,Molecular biology ,Malaria ,030104 developmental biology ,Infectious Diseases ,chemistry ,SYBR Green I ,Parasitology ,Ethidium bromide ,Cloning - Abstract
Background Molecular and genetic studies of blood-stage Plasmodium falciparum parasites require limiting dilution cloning and prolonged cultivation in microplates. The entire process is laborious and subject to errors due to inaccurate dilutions at the onset and failed detection of parasite growth in individual microplate wells. Methods To precisely control the number of parasites dispensed into each microplate well, parasitaemia and total cell counts were determined by flow cytometry using parasite cultures stained with ethidium bromide or SYBR Green I. Microplates were seeded with 0.2 or 0.3 infected cells/well and cultivated with fresh erythrocytes. The c-SNARF fluorescent pH indicator was then used to reliably detect parasite growth. Results Flow cytometry required less time than the traditional approach of estimating parasitaemia and cell numbers by microscopic examination. The resulting dilutions matched predictions from Poisson distribution calculations and yielded clonal lines. Addition of c-SNARF to media permitted rapid detection of parasite growth in microplate wells with high confidence. Conclusion The combined use of flow cytometry for precise dilution and the c-SNARF method for detection of growth improves limiting dilution cloning of P. falciparum. This simple approach saves time, is scalable, and maximizes identification of desired parasite clones. It will facilitate DNA transfection studies and isolation of parasite clones from ex vivo blood samples.
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- 2021
106. [4 + 2] cycloaddition reactions of β-naphtha-1-thioquinones generated from 2-naphthols and DAST
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Yang Geng, Xianying Gao, Apeng Liang, Jingya Li, Dapeng Zou, Yangjie Wu, and Yusheng Wu
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Cycloaddition Reaction ,Diethylamines ,Organic Chemistry ,Alkanes ,Solvents ,Stereoisomerism ,Fluorine ,Naphthols ,Physical and Theoretical Chemistry ,Biochemistry - Abstract
A novel protocol for the construction of diverse dehydro-2-naphthol-1-sulphides and naphtha-oxathiane derivatives via in situ [4 + 2] cycloadditions of β-naphtha-1-thioquinones generated from 2-naphthols and DAST has been developed.
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- 2022
107. Phylogenetic Analysis and Characterization of Odorous Compound-Producing Actinomycetes in Sediments in the Sanbe Reservoir, A Drinking Water Reservoir in Japan
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Shohei Hayashi, Shingo Masuki, Koichi Furuta, Shinichi Doi, Sangyeob Kim, and Yasushi Seike
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Actinobacteria ,Japan ,Drinking Water ,RNA, Ribosomal, 16S ,Odorants ,Actinomyces ,General Medicine ,Naphthols ,Cyanobacteria ,Applied Microbiology and Biotechnology ,Microbiology ,Ecosystem ,Phylogeny - Abstract
Odor caused by the presence of geosmin and 2-methylisoborneol (2-MIB) in aquatic ecosystems leads to considerable economic loss worldwide. The odorous compounds are primarily produced by cyanobacteria and actinomycetes. While the contribution of odorous compounds-producing cyanobacteria has been thoroughly investigated, the production of geosmin and 2-MIB by actinomycetes in aquatic ecosystems is poorly understood. In this study, we isolated geosmin and/or 2-MIB-producing actinomycetes in sediments collected from the Sanbe Reservoir, Japan, identified the biosynthetic gene of geosmin and 2-MIB, and investigated the production of the odorous compounds by the isolated strains. Partial sequence of 16S rRNA and the biosynthetic genes was determined to analyze the phylogenetic relationship among the strains. The geosmin and 2-MIB concentrations in the culture of the isolated strains were measured using gas chromatography mass spectrometry. Fifty-four strains of odorous compounds-producing and non-geosmin-producing actinomycetes were isolated from sediments from the Sanbe Reservoir. Diverse actinomycetes were identified and many of them produced geosmin and/or 2-MIB. Many odorous compounds-producing actinomycetes were phylogenetically different from previously reported producing actinomycetes. The producing ability of the odorous compounds of the isolated strains in this study was not significantly related with the phylogenetic groups of 16S rRNA and the biosynthetic genes. The findings suggest that the odorous compounds-producing actinomycetes in the sediments are diverse and different from previously reported strains.
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- 2022
108. Enantioselective Dearomative Cyclization Enabled by Asymmetric Cooperative Gold Catalysis
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Ke Zhao, Philip Kohnke, Ziguang Yang, Xinpeng Cheng, Shu‐Li You, and Liming Zhang
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Cyclization ,Stereoisomerism ,General Medicine ,Gold ,Naphthols ,General Chemistry ,Ligands ,Catalysis - Abstract
A gold(I)-catalyzed enantioselective dearomatization is achieved via metal-chiral ligand cooperation. A new and divergent synthesis of chiral bifunctional binaphthyl-2-ylphosphines is developed to allow rapid access to these ligands, which in turn facilitate the application of this chemistry to a broad substrate scope including 1-naphthols, 2-naphthols, and phenols. Enantiomeric excesses up to 98 % are achieved via selective acceleration of one enantiomer formation enabled by hydrogen bonding between substrate and ligand remote basic group. DFT calculations lend support to the cooperative catalysis and substantiate the reaction stereochemical outcomes.
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- 2022
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109. Cytidine deaminase deficiency in tumor cells is associated with sensitivity to a naphthol derivative and a decrease in oncometabolite levels
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Hamza Mameri, Géraldine Buhagiar-Labarchède, Gaëlle Fontaine, Céline Corcelle, Caroline Barette, Rosine Onclercq-Delic, Claire Beauvineau, Florence Mahuteau-Betzer, Mounira Amor-Guéret, Ingénierie des Agro-polymères et Technologies Émergentes (UMR IATE), Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Institut Agro Montpellier, Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Université de Montpellier (UM), Intégrité du génome, ARN et cancer, Institut Curie [Paris]-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Chimie et modélisation pour la biologie du cancer (CMBC), Institut Curie [Paris]-Institut National de la Santé et de la Recherche Médicale (INSERM)-Institut de Chimie du CNRS (INC)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Genetics and Chemogenomics (GenChem), BioSanté (UMR BioSanté), Institut National de la Santé et de la Recherche Médicale (INSERM)-Institut de Recherche Interdisciplinaire de Grenoble (IRIG), Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Grenoble Alpes (UGA)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Institut de Recherche Interdisciplinaire de Grenoble (IRIG), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Grenoble Alpes (UGA), and Cancéropôle Ile de France, Ligue Nationale contre le Cancer, Fondation ARC and Curie Cancer (Institut Carnot) , Institut Curie(Innov’booster program, Institut Carnot ), CNRS (Prematuration program ) and Ligue Nationale Contre le Cancer (Comité de l'Essonne).
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Pharmacology ,Cell metabolism ,Cytidine deaminase ,Cancer therapy ,[SDV.CAN]Life Sciences [q-bio]/Cancer ,Naphthols ,Cell Biology ,Cellular and Molecular Neuroscience ,MAPT ,Humans ,Molecular Medicine ,Molecular Biology ,HeLa Cells ,Drug sensitivity - Abstract
Identifying new molecular targets for novel anticancer treatments is a major challenge in clinical cancer research. We have shown that cytidine deaminase (CDA) expression is downregulated in about 60% of cancer cells and tissues. In this study, we aimed to develop a new anticancer treatment specifically inhibiting the growth of CDA-deficient tumor cells. High-throughput screening of a chemical library led to the identification of a naphthol derivative, X55, targeting CDA-deficient tumor cells preferentially, without affecting the growth of non-tumoral cells regardless of CDA expression status. Metabolomic profiling revealed that CDA-deficient HeLa cells differed markedly from control HeLa cells. X55 treatment had a moderate effect on control cells, but greatly disturbed the metabolome of CDA-deficient HeLa cells, worsening the deregulation of many metabolites. In particular, the levels of the three oncometabolites, fumarate, succinate and 2-hydroxyglutarate, were significantly lower in CDA-depleted cells, and this decrease in levels was exacerbated by X55 treatment, revealing an unexpected link between CDA deficiency, mitochondrial function and X55 response. Finally, we identified strong downregulation of MAPT (encoding Tau, a microtubule associated protein) expression as a reliable predictive marker for tumor cell X55 sensitivity.
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- 2022
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110. Fabrication of a novel electrochemical immunosensor for the sensitive detection of carcinoembryonic antigen using a double signal attenuation strategy
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Xiao Wang, Xiaochen Liao, Bingjian Zhang, Siyu Chen, Mengmeng Zhang, Lisha Mei, Li Zhang, Xiuwen Qiao, and Chenglin Hong
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Immunoassay ,Polymers ,Iron ,Metal Nanoparticles ,Biosensing Techniques ,Naphthols ,Electrochemical Techniques ,Hydrogen Peroxide ,Silicon Dioxide ,Biochemistry ,Ferric Compounds ,Analytical Chemistry ,Carcinoembryonic Antigen ,Peroxidases ,Limit of Detection ,Environmental Chemistry ,Gold ,Spectroscopy - Abstract
Carcinoembryonic antigen (CEA), an acidic protein, is a characteristic antigen produced by the tumor of various cancers (eg, breast, cervical, rectal, lung, etc.). Therefore, the detection of cancer antigens is very important for the early diagnosis and treatment of cancer. In this study, a novel of "signal off" strategy for electrochemical immunosensor was developed to detect CEA. To this end, Prussian blue nanoparticles (PB NPs), an electroactive substance, were used as the immunological platform. In addition, CuO
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- 2022
111. A rapid and closed-tube method based on the dual-color fluorescence loop-mediated isothermal amplification for visual detection of Atlantic salmon (Salmo salar)
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Yi Li, Hanyue Xue, Yanjing Fei, Ying Yang, Danping Huang, Libin Wang, Xiaohui Xiong, and Xiong Xiong
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Excipients ,Hydroxyl Radical ,Salmo salar ,Animals ,Biological Assay ,General Medicine ,Naphthols ,Food Science ,Analytical Chemistry - Abstract
Loop-mediated isothermal amplification (LAMP) visual detection based on hydroxyl naphthol blue (HNB) and SYTO 9 is often confounded by the narrow color variation window and the requirement of empirical preset of cutoff intensity value. To improve the suitability for naked-eye inspection, the present work proposed a strategy based on the fluorescence property of SYTO 9 and HNB to enlarge the contrast and a novel dual-color fluorescence LAMP (dfLAMP) assay was developed for visual detection of Atlantic salmon. Specifically, HNB of 26.25 μM, blended with SYTO 9 of 0.75-1.5 μM, was added in the mixture before amplification, producing light green fluorescence for both positive and negative samples. After amplification, green or yellow-green fluorescence was observed for positive samples, while only orange-red fluorescence emitted for negative ones, enabling an easy and rapid distinguish. The optimized dfLAMP assay has proved its specificity and can detect as little as 1 fg Atlantic salmon DNA.
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- 2022
112. HuR up-regulates cell surface PD-L1 via stabilizing CMTM6 transcript in cancer
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Yanbin Liu, Yanli Wei, Mingming Zhang, Hui Zhang, and Xingzhi Li
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0301 basic medicine ,Cancer Research ,T-Lymphocytes ,medicine.medical_treatment ,Programmed Cell Death 1 Receptor ,Cell ,Naphthols ,B7-H1 Antigen ,Article ,ELAV-Like Protein 1 ,Mice ,03 medical and health sciences ,0302 clinical medicine ,Immune system ,Cancer immunotherapy ,Neoplasms ,PD-L1 ,Genetics ,medicine ,Animals ,Humans ,RNA, Messenger ,Furans ,3' Untranslated Regions ,Molecular Biology ,MARVEL Domain-Containing Proteins ,biology ,Immunity ,Cancer ,medicine.disease ,Cell biology ,Gene Expression Regulation, Neoplastic ,030104 developmental biology ,medicine.anatomical_structure ,Tumor progression ,030220 oncology & carcinogenesis ,Cancer cell ,biology.protein ,Heterografts ,Interleukin-2 ,Tumour immunology ,Antibody ,Myelin Proteins - Abstract
Despite the well-established role of CMTM6 in the stabilization of cell surface PD-L1 in cancer cells, the mechanisms underlying CMTM6 expression and regulation are still largely unknown. Here we unexpectedly find a strikingly positive correlation between CMTM6 and Hu-Antigen R (HuR) expression in most types of cancer. Mechanistically, we elucidate HuR stabilizes CMTM6 mRNA via direct association with AU-rich elements (AREs) in its 3′UTR and predominantly up-regulates CMTM6, which is readily abolished by HuR-specific inhibitor, MS-444. Phenotypically, we notice abundant cell surface PD-L1 in HuR-high cancer cells, which significantly inhibits immune activation of co-cultured T cells as indicated by IL-2 production. Treatment with MS-444 completely relieves immune suppression imposed by HuR-overexpression and further stimulates immune responses. Ectopic HuR accelerates allograft tumor progression in vivo, which is greatly compromised by simultaneous administration with MS-444. Our study uncovers a novel mechanism in control of CMTM6 and therefore PD-L1 expression, and suggests the potential of combining HuR inhibitor with PD-1/PD-L1 antibodies for cancer immunotherapy.
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- 2021
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113. Granulocyte-Macrophage Colony-Stimulating Factor-Activated Neutrophils Express B7-H4 That Correlates with Gastric Cancer Progression and Poor Patient Survival
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Fang-yuan Mao, Liu-sheng Peng, Kun Fan, Yong-sheng Teng, Ping Cheng, Zong-Bao Yan, Zhi-Guo Shan, Yong-liang Zhao, and Yuan Zhuang
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Article Subject ,Neutrophils ,Immunology ,Naphthols ,Neutrophil Activation ,Immune tolerance ,Flow cytometry ,03 medical and health sciences ,0302 clinical medicine ,Stomach Neoplasms ,Immune Tolerance ,medicine ,Humans ,Immunology and Allergy ,STAT3 ,Cells, Cultured ,Janus Kinases ,Neoplasm Staging ,Sulfonamides ,biology ,medicine.diagnostic_test ,Chemistry ,Granulocyte-Macrophage Colony-Stimulating Factor ,General Medicine ,V-Set Domain-Containing T-Cell Activation Inhibitor 1 ,RC581-607 ,Intercellular Adhesion Molecule-1 ,Survival Analysis ,Gene Expression Regulation, Neoplastic ,Phenotype ,Granulocyte macrophage colony-stimulating factor ,Tumor progression ,030220 oncology & carcinogenesis ,Disease Progression ,biology.protein ,Cancer research ,Immunologic diseases. Allergy ,Signal transduction ,Janus kinase ,Ex vivo ,Signal Transduction ,Research Article ,030215 immunology ,medicine.drug - Abstract
Neutrophils are prominent components of gastric cancer (GC) tumors and exhibit distinct phenotypes in GC environment. However, the phenotype, regulation, and clinical relevance of neutrophils in human GC are presently unknown. Here, immunohistochemistry, real-time PCR, and flow cytometry analyses were performed to examine levels and phenotype of neutrophils in samples from 41 patients with GC, and also isolated, stimulated, and/or cultured neutrophils for in vitro regulation assays. Finally, we performed Kaplan-Meier plots for overall survival by using the log-rank test to evaluate the clinical relevance of neutrophils and their subsets. In our study, neutrophils in tumor tissues were significantly higher than those in nontumor tissues and were positively associated with tumor progression but negatively correlated with GC patient survival. Most intratumoral neutrophils showed an activated CD54+ phenotype and expressed high-level immunosuppressive molecule B7-H4. Tumor tissue culture supernatants from GC patients induced neutrophils to express CD54 and B7-H4 in both time-dependent and dose-dependent manners. Locally enriched CD54+ neutrophils and B7-H4+ neutrophils positively correlated with increased granulocyte-macrophage colony-stimulating factor (GM-CSF) detection ex vivo, and in vitro GM-CSF induced the expression of CD54 and B7-H4 on neutrophils in a time-dependent and dose-dependent manner. Moreover, GC tumor-derived GM-CSF activated neutrophils and induced neutrophil B7-H4 expression via Janus kinase (JAK)-signal transducer and activator of transcription 3 (STAT3) signaling pathway activation. Furthermore, higher intratumoral B7-H4+ neutrophil percentage/number was found in GC patients with advanced tumor node metastasis stage and reduced overall survival following surgery. Our results illuminate a novel regulating mechanism of B7-H4 expression on tumor-activated neutrophils in GC, suggesting that functional inhibition of these novel GM-CSF-B7-H4 pathways may be a suitable therapeutic strategy to treat the immune tolerance feature of GC.
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- 2021
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114. Rhodium(III)-Catalyzed [4+2] Annulation via C-H Activation: Synthesis of Multi-Substituted Naphthalenone Sulfoxonium Ylides
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Xiaohan Song, Xu Han, Rui Zhang, Hong Liu, and Jiang Wang
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rhodium(III) ,sulfoxonium ylides ,naphthols ,Organic chemistry ,QD241-441 - Abstract
A convenient Rh(III)-catalyzed C-H activation and cascade [4+2] annulation for the synthesis of naphthalenone sulfoxonium ylides has been developed. This method features perfect regioselectivity, mild and redox-neutral reaction conditions, and broad substrate tolerance with good to excellent yields. Preliminary mechanistic experiments were conducted and a plausible reaction mechanism was proposed. The new type naphthalenone sulfoxonium ylides could be further transformed into multi-substituted naphthols, which demonstrates the practical utility of this methodology.
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- 2019
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115. Expression and kinetic analysis of carboxylesterase LmCesA1 from Locusta migratoria
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Jianqin Zhang, Daqi Li, Xueyao Zhang, Wen Ma, and Fei Yin
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0106 biological sciences ,0301 basic medicine ,Insecticides ,Gene Expression ,Locusta migratoria ,Bioengineering ,Sf9 ,Naphthols ,01 natural sciences ,Applied Microbiology and Biotechnology ,Carboxylesterase ,law.invention ,03 medical and health sciences ,chemistry.chemical_compound ,Malaoxon ,law ,010608 biotechnology ,Sf9 Cells ,Animals ,chemistry.chemical_classification ,Pyrethroid ,Temperature ,General Medicine ,Hydrogen-Ion Concentration ,Recombinant Proteins ,Kinetics ,030104 developmental biology ,Enzyme ,Deltamethrin ,chemistry ,Biochemistry ,Recombinant DNA ,Insect Proteins ,Malathion ,Biotechnology - Abstract
To investigate the biochemical characterization of the carboxylesterase LmCesA1 from Locusta migratoria. We expressed recombinant LmCesA1 in Sf9 cells by using the Bac-to-bac baculovirus expression system. Enzyme kinetic assays showed that the Km values of LmCesA1 for α-naphthyl acetate (α-NA) and β-naphthyl acetate (β-NA) were 0.08 ± 0.01 mM and 0.22 ± 0.03 mM, respectively, suggesting that LmCesA1 has a higher affinity for α-NA. LmCesA1 retained its enzymatic activity during incubations at pH 7–10 and at 10–30 °C. In an inhibition experiment, two organophosphate pesticides (malaoxon and malathion) and one pyrethroid pesticide (deltamethrin) showed different inhibition profiles against purified LmCesA1. Recombinant LmCesA1 activity was significantly inhibited by malaoxon in vitro. UPLC analysis showed that no metabolites were detected. These results suggest that overexpression of LmCesA1 enhances malathion sequestration to confer malathion tolerance in L. migratoria.
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- 2021
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116. β-Cyclodextrin-conjugated phthalocyanines as water-soluble and recyclable sensitisers for photocatalytic applications
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Dennis K. P. Ng and Xiao-Fei Chen
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Indoles ,Supramolecular chemistry ,chemistry.chemical_element ,Naphthols ,Zinc ,Isoindoles ,Conjugated system ,Catalysis ,Coordination Complexes ,Materials Chemistry ,Furans ,Photodegradation ,chemistry.chemical_classification ,Molecular Structure ,Cyclodextrin ,beta-Cyclodextrins ,Energy conversion efficiency ,Metals and Alloys ,Water ,General Chemistry ,Photochemical Processes ,Combinatorial chemistry ,Surfaces, Coatings and Films ,Electronic, Optical and Magnetic Materials ,Solubility ,chemistry ,Ceramics and Composites ,Photocatalysis ,Photooxygenation ,Chlorophenols - Abstract
Two zinc(ii) phthalocyanines substituted with two and four permethylated β-cyclodextrin moieties at the α positions have been synthesised and immobilised on the surface of adamantane-modified silica nanoparticles through host-guest interactions. These molecular and supramolecular systems can catalyse the photooxygenation of 1-naphthol and 2-furoic acid in organic and aqueous media with high conversion efficiency and reaction yield, and photodegradation of 2-chlorophenol in water. Having a higher photostability and recyclability, the supramolecular nanosystems are particularly promising for these photocatalytic applications.
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- 2021
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117. Transition-Metal-Free Alkylative Aromatization of Tetralone Using Alcohol/Amino Alcohol towards the Synthesis of Bioactive Naphthol and Benzo[
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Akash S, Ubale, Gokul S, Londhe, Moseen A, Shaikh, and Boopathy, Gnanaprakasam
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Indoles ,Ethanol ,Transition Elements ,Naphthols ,Amino Alcohols ,Catalysis ,Tetralones - Abstract
Herein, we report alkylative aromatization of tetralone for the synthesis of bioactive naphthols and benzo[
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- 2022
118. 6-Bromo-2-naphthol from Silene armeria extract sensitizes Acinetobacter baumannii strains to polymyxin
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Mingyeong, Kang, Wonjae, Kim, Jaebok, Lee, Hye Su, Jung, Che Ok, Jeon, and Woojun, Park
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Acinetobacter baumannii ,Multidisciplinary ,Plant Extracts ,Drug Resistance, Multiple, Bacterial ,Drug Synergism ,Microbial Sensitivity Tests ,Naphthols ,Polymyxins ,Silene ,Acinetobacter Infections ,Anti-Bacterial Agents ,Polymyxin B - Abstract
The overuse of antibiotics has led to the emergence of multidrug-resistant bacteria, which are resistant to various antibiotics. Combination therapies using natural compounds with antibiotics have been found to have synergistic effects against several pathogens. Synergistic natural compounds can potentiate the effects of polymyxins for the treatment of Acinetobacter baumannii infection. Out of 120 types of plant extracts, only Silene armeria extract (SAE) showed a synergistic effect with polymyxin B (PMB) in our fractional inhibitory concentration and time-kill analyses. The survival rate of G. mellonella infected with A. baumannii ATCC 17978 increased following the synergistic treatment. Interestingly, the addition of osmolytes, such as trehalose, canceled the synergistic effect of SAE with PMB; however, the underlying mechanism remains unclear. Quadrupole time-of-flight liquid chromatography-mass spectrometry revealed 6-bromo-2-naphthol (6B2N) to be a major active compound that exhibited synergistic effects with PMB. Pretreatment with 6B2N made A. baumannii cells more susceptible to PMB exposure in a time- and concentration-dependent manner, indicating that 6B2N exhibits consequential synergistic action with PMB. Moreover, the exposure of 6B2N-treated cells to PMB led to higher membrane leakage and permeability. The present findings provide a promising approach for utilizing plant extracts as adjuvants to reduce the toxicity of PMB in A. baumannii infection.
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- 2022
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119. Synthesis and Evaluation of Anti-HIV Activity of Mono- and Di-Substituted Phosphonamidate Conjugates of Tenofovir
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Aaminat Qureshi, Louise A. Ouattara, Naglaa Salem El-Sayed, Amita Verma, Gustavo F. Doncel, Muhammad Iqbal Choudhary, Hina Siddiqui, and Keykavous Parang
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Alanine ,Anti-HIV Agents ,Nucleotides ,Organic Chemistry ,Pharmaceutical Science ,Esters ,HIV Infections ,Naphthols ,Amides ,Analytical Chemistry ,Chemistry (miscellaneous) ,Drug Discovery ,HIV-1 ,Molecular Medicine ,Humans ,anti-HIV activity ,ester conjugates of TFV ,phosphonamidate ,tenofovir (TFV) ,tenofovir alafenamide (TAF) ,Physical and Theoretical Chemistry ,Tenofovir ,Oleic Acid - Abstract
The activity of nucleoside and nucleotide analogs as antiviral agents requires phosphorylation by endogenous enzymes. Phosphate-substituted analogs have low bioavailability due to the presence of ionizable negatively-charged groups. To circumvent these limitations, several prodrug approaches have been proposed. Herein, we hypothesized that the conjugation or combination of the lipophilic amide bond with nucleotide-based tenofovir (TFV) (1) could improve the anti-HIV activity. During the current study, the hydroxyl group of phosphonates in TFV was conjugated with the amino group of L-alanine, L-leucine, L-valine, and glycine amino acids and other long fatty ester hydrocarbon chains to synthesize 43 derivatives. Several classes of derivatives were synthesized. The synthesized compounds were characterized by 1H NMR, IR, UV, and mass spectrometry. In addition, several of the synthesized compounds were evaluated as racemic mixtures for anti-HIV activity in vitro in a single round infection assay using TZM-bl cells at 100 ng/mL. TFV (1) was used as a positive control and inhibited HIV infection by 35%. Among all the evaluated compounds, the disubstituted heptanolyl ester alanine phosphonamidate with naphthol oleate (69), pentanolyl ester alanine phosphonamidate with phenol oleate (62), and butanolyl ester alanine phosphonamidate with naphthol oleate (87) ester conjugates of TFV were more potent than parent drug TFV with 79.0%, 76.5%, 71.5% inhibition, respectively, at 100 ng/mL. Furthermore, two fatty acyl amide conjugates of tenofovir alafenamide (TAF) were synthesized and evaluated for comparative studies with TAF and TFV conjugates. Tetradecanoyl TAF conjugate 95 inhibited HIV infection by 99.6% at 100 ng/mL and showed comparable activity to TAF (97–99% inhibition) at 10–100 ng/mL but was more potent than TAF when compared at molar concentration.
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- 2022
120. Chemoenzymatic total synthesis of nodulones C and D using a naphthol reductase of
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Tanaya, Manna, Anshul, Rajput, Nirmal, Saha, Amit, Mondal, Subhas Chandra, Debnath, and Syed Masood, Husain
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Magnaporthe ,Oryza ,Naphthols ,Oxidoreductases ,Pyricularia grisea - Abstract
Herein, the asymmetric and chemoenzymatic synthesis of (
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- 2022
121. Pamoic acid is an inhibitor of HMGB1•CXCL12 elicited chemotaxis and reduces inflammation in murine models of Pseudomonas aeruginosa pneumonia
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Federica De Leo, Alice Rossi, Francesco De Marchis, Cristina Cigana, Medede Melessike, Giacomo Quilici, Ida De Fino, Malisa Vittoria Mantonico, Chantal Fabris, Alessandra Bragonzi, Marco Emilio Bianchi, and Giovanna Musco
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Inflammation ,Chemotaxis ,Naphthols ,Chemokine CXCL12 ,Mice, Inbred C57BL ,Disease Models, Animal ,Mice ,Pseudomonas aeruginosa ,Pneumonia, Bacterial ,Genetics ,Animals ,Molecular Medicine ,HMGB1 Protein ,Molecular Biology ,Genetics (clinical) - Abstract
Background High-mobility group box 1 protein (HMGB1) is an ubiquitous nuclear protein that once released in the extracellular space acts as a Damage Associated Molecular Pattern and promotes inflammation. HMGB1 is significantly elevated during Pseudomonas aeruginosa infections and has a clinical relevance in respiratory diseases such as Cystic Fibrosis (CF). Salicylates are HMGB1 inhibitors. To address pharmacological inhibition of HMGB1 with small molecules, we explored the therapeutic potential of pamoic acid (PAM), a salicylate with limited ability to cross epithelial barriers. Methods PAM binding to HMGB1 and CXCL12 was tested by Nuclear Magnetic Resonance Spectroscopy using chemical shift perturbation methods, and inhibition of HMGB1·CXCL12-dependent chemotaxis was investigated by cell migration experiments. Aerosol delivery of PAM, with single or repeated administrations, was tested in murine models of acute and chronic P. aeruginosa pulmonary infection in C57Bl/6NCrlBR mice. PAM efficacy was evaluated by read-outs including weight loss, bacterial load and inflammatory response in lung and bronco-alveolar lavage fluid. Results Our data and three-dimensional models show that PAM is a direct ligand of both HMGB1 and CXCL12. We also showed that PAM is able to interfere with heterocomplex formation and the related chemotaxis in vitro. Importantly, PAM treatment by aerosol was effective in reducing acute and chronic airway murine inflammation and damage induced by P. aeruginosa. The results indicated that PAM reduces leukocyte recruitment in the airways, in particular neutrophils, suggesting an impaired in vivo chemotaxis. This was associated with decreased myeloperoxidase and neutrophil elastase levels. Modestly increased bacterial burdens were recorded with single administration of PAM in acute infection; however, repeated administration in chronic infection did not affect bacterial burdens, indicating that the interference of PAM with the immune system has a limited risk of pulmonary exacerbation. Conclusions This work established the efficacy of treating inflammation in chronic respiratory diseases, including bacterial infections, by topical delivery in the lung of PAM, an inhibitor of HMGB1.
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- 2022
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122. The Ubiquitous Soil Terpene Geosmin Acts as a Warning Chemical
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Liana Zaroubi, Imge Ozugergin, Karina Mastronardi, Anic Imfeld, Chris Law, Yves Gélinas, Alisa Piekny, and Brandon L. Findlay
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Soil ,Ecology ,Terpenes ,Environmental Microbiology ,Animals ,Naphthols ,Caenorhabditis elegans ,Applied Microbiology and Biotechnology ,Food Science ,Biotechnology - Abstract
Known as the smell of earth after rain, geosmin is an odorous terpene detectable by humans at picomolar concentrations. Geosmin production is heavily conserved in actinobacteria, myxobacteria, cyanobacteria, and some fungi, but its biological activity is poorly understood. We theorized that geosmin was an aposematic signal used to indicate the unpalatability of toxin-producing microbes, discouraging predation by eukaryotes. Consistent with this hypothesis, we found that geosmin altered the behavior of the bacteriophagous nematode Caenorhabditis elegans on agar plates in the absence of bacteria. Normal movement was restored in mutant worms lacking differentiated ASE (amphid neurons, single ciliated endings) neurons, suggesting that geosmin is a taste detected by the nematodal gustatory system. In a predation assay, geosmin and the related terpene 2-methylisoborneol reduced grazing on the bacterium Streptomyces coelicolor. Predation was restored by the removal of both terpene biosynthetic pathways or the introduction of C. elegans that lacked differentiated ASE taste neurons, leading to the apparent death of both bacteria and worms. While geosmin and 2-methylisoborneol appeared to be nontoxic, grazing triggered bacterial sporulation and the production of actinorhodin, a pigment coproduced with a number of toxic metabolites. In this system, geosmin thus appears to act as a warning signal indicating the unpalatability of its producers and reducing predation in a manner that benefits predator and prey. This suggests that molecular signaling may affect microbial predator-prey interactions in a manner similar to that of the well-studied visual markers of poisonous animal prey. IMPORTANCE One of the key chemicals that give soil its earthy aroma, geosmin is a frequent water contaminant produced by a range of unrelated microbes. Many animals, including humans, are able to detect geosmin at minute concentrations, but the benefit that this compound provides to its producing organisms is poorly understood. We found that geosmin repelled the bacterial predator Caenorhabditis elegans in the absence of bacteria and reduced contact between the worms and the geosmin-producing bacterium Streptomyces coelicolor in a predation assay. While geosmin itself appears to be nontoxic to C. elegans, these bacteria make a wide range of toxic metabolites, and grazing on them harmed the worms. In this system, geosmin thus appears to indicate unpalatable bacteria, reducing predation and benefiting both predator and prey. Aposematic signals are well known in animals, and this work suggests that metabolites may play a similar role in the microbial world.
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- 2022
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123. Lactose hydrate can increase the transcellular permeability of β-naphthol in rat jejunum and ileum
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Yusuke Takizawa, Ryoka Nakamura, Takuro Kurita, and Takanori Nakajima
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Galectins ,Water ,Lactose ,General Medicine ,Naphthols ,Permeability ,Rats ,Jejunum ,Intestinal Absorption ,Ileum ,Genetics ,Animals ,Humans ,Caco-2 Cells ,Intestinal Mucosa ,Molecular Biology - Abstract
The unstirred water layer (UWL) is an integral part of the apical surface of mucosal epithelia and comprises mucins (MUC), for which there are many molecular species. Galectins, a family of β-galactoside-binding lectins, form a lattice barrier on surface epithelial cells by interacting with MUC. Lactose inhibits the galectin-MUC interaction. Therefore, the present study investigated the galectin-MUC interaction in the mucosa of the gastrointestinal tract and its role in intestinal barrier functions.The effects of lactose hydrate (LH) on the membrane permeability of the rat small intestine and Caco-2 cells were examined. LH enhanced the membrane permeability of the rat small intestine, which contains the UWL, via a transcellular route, for which the UWL is the rate limiting factor. The membrane permeability of Caco-2 cells, in which the UWL is insufficient, was not affected by LH. The apparent permeability coefficient (PThe present results demonstrate that the physical barrier has an important function in gastrointestinal membrane permeability, and LH-induced changes increase the transcellular permeability of β-naphthol in rat small intestine.
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- 2022
124. Urea derivative organocatalyzed enantioselective Friedel-Crafts alkylation of α-naphthols with isatins
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Liming Wang, Zhe Chen, Huiting Jiang, Jie Zhang, and Ying Jin
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Pharmacology ,Isatin ,Alkylation ,Molecular Structure ,Organic Chemistry ,Drug Discovery ,Urea ,Stereoisomerism ,Naphthols ,Spectroscopy ,Catalysis ,Analytical Chemistry - Abstract
An organocatalytic enantioselective Friedel-Crafts alkylation of α-naphthols with isatin derivatives was catalyzed by Takemoto-type urea catalyst to give optical active 3-(naphthalen-2-yl)-3-hydroxy-2-oxindoles in 75%-92% yields with up to 95% enantiomeric excess (ee) value. The catalyst type and the substrate scope were broadened in this methodology.
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- 2022
125. Improving E. coli organic solvent tolerance by 1,4-dihydroxy-2-naphthoic acid
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Noriyuki Doukyu, Hideyuki Fujisawa, and Ryota Saito
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Escherichia coli Proteins ,Organic Chemistry ,General Medicine ,Gene Expression Regulation, Bacterial ,Naphthols ,Applied Microbiology and Biotechnology ,Biochemistry ,Analytical Chemistry ,Bacterial Proteins ,Escherichia coli ,Solvents ,Trans-Activators ,Molecular Biology ,Biotechnology - Abstract
Improving the organic solvent tolerance of bacteria is beneficial for the bioproduction of various valuable chemicals. In this study, we found that 1,4-dihydroxy-2-naphthoic acid (DHNA), known as a prebiotic, increased organic solvent tolerance in Escherichia coli. The AcrAB‒TolC multidrug efflux pump contributes to the intrinsic organic solvent tolerance of E. coli. The addition of DHNA increased this pump's expression level. Transcriptional activators MarA, SoxS, and Rob proteins are known to control the expression of marA/soxS/rob regulon genes, including acrAB and tolC. Evaluation of the organic solvent tolerances of DmarA mutant, DsoxS mutant, and Drob mutant showed that DmarA mutant and DsoxS mutant did not improve organic solvent tolerance by the addition of DHNA. In addition, DHNA increased the promoter activities of both marA and soxS. These results indicated that DHNA induces the AcrAB‒TolC pump through both the marRAB system and the soxRS system.
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- 2022
126. Silver-catalyzed chemodivergent assembly of aminomethylated isochromenes and naphthols
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Bangkui Yu, Renbin Huang, Renren Li, Haocheng Zhang, and Hanmin Huang
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Silver ,Cyclization ,Alkynes ,Materials Chemistry ,Metals and Alloys ,Ceramics and Composites ,General Chemistry ,Naphthols ,Catalysis ,Surfaces, Coatings and Films ,Electronic, Optical and Magnetic Materials - Abstract
A silver-catalyzed chemodivergent cyclization of alkyne-tethered aldehydes with aminals to aminomethylated 1H-isochromenes and naphthols is described by tuning the catalyst system and reaction conditions.
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- 2022
127. Production of jet fuels from coal-derived liquids
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Knudson, C
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- 1990
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128. Rhodium-Catalyzed Synthesis of Multiaryl-substituted Naphthols via a Removable Directing Group.
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Wang, Lianhui, Yu, Yunliang, Yang, Mengqi, Kuai, Changsheng, Cai, Dingding, Yu, Jinfeng, and Cui, Xiuling
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- *
RHODIUM , *CATALYSIS , *CHEMICAL synthesis , *DIMERS , *FUNCTIONAL groups - Abstract
Arene homologation employing internal alkynes as coupling partners and 2-pyridyloxyl as directing group through dual C−H bond functionalization was accomplished using (pentamethylcyclopentadienyl)-rhodium(III) chloride dimer as a pre-catalyst. This protocol proved tolerant of synthetically valuable functional groups, and provided an expeditious access to highly congested naphthalene derivatives in moderate to good yields. Furthermore, the pyridyl moiety could be removed to furnish the versatile ( OH)-free naphthols. [ABSTRACT FROM AUTHOR]
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- 2017
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129. Sustainable and Site-Selective C−H Sulfenylation of Aromatic Compounds with Thiol using Catalytic Graphene Oxide and NaI.
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Choudhury, Prasun, Roy, Babli, and Basu, Basudeb
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GRAPHENE oxide ,AROMATIC compounds ,RESORCINOL - Abstract
Graphene oxide (GO) in combination with NaI is used as the catalytic system for site-selective C−H sulfenylation of 1 H-indole, 2-naphthol, resorcinol and 2-naphthylamines with thiols. The reaction is usually achieved in the presence of metal catalysts as well as under metal-free conditions using iodine and a strong oxidizing agent. The present protocol avoids the use of any metal catalysts, strong oxidizing agents and the use of thiols instead of other sulfur-based reagents making it atom-economic and environmentally benign. Broader tolerance to functional groups has been tested and a plausible mechanism is proposed. The recovered GO can be recycled without significant loss in catalytic activity up to four runs. [ABSTRACT FROM AUTHOR]
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- 2017
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130. Ultrafast photo-induced charge transfer of 1-naphthol and 2-naphthol to halocarbon solvents.
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Chaudhuri, Subhajyoti, Rudshteyn, Benjamin, Prémont-Schwarz, Mirabelle, Pines, Dina, Pines, Ehud, Huppert, Dan, Nibbering, Erik T.J., and Batista, Victor S.
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FLUORESCENCE quenching , *LUMINESCENCE quenching , *NAPHTHOL , *PHENOL , *QUANTUM chemistry , *HALOCARBONS - Abstract
We explore the fluorescence quenching of 1-naphthol and 2-naphthol in halocarbon solvents by using time-correlated single-photon-counting, femtosecond IR-spectroscopy and quantum chemistry computations. We find that halocarbon solvents facilitate a de-excitation mechanism via solute-solvent electron transfer. Decay rates are modulated by close contact interactions between the π-electronic structure of naphthols and halocarbon molecules in their first solvation shell. 1-naphthol exhibits faster decay rates than 2-naphthol due to closer interactions with the solvent. [ABSTRACT FROM AUTHOR]
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- 2017
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131. Asymmetric dearomative spirolactonization of naphthols using λ3-iodanes under chiral phase-transfer catalysis.
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Antien, Kevin, Viault, Guillaume, Pouységu, Laurent, Peixoto, Philippe A., and Quideau, Stéphane
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NAPHTHOL , *ORGANIC reaction mechanisms , *PHASE-transfer catalysis , *CINCHONA alkaloids , *AMMONIUM salts - Abstract
The asymmetric phase-transfer catalytic effect of chiral Cinchona alkaloid-derived quaternary ammonium salts was investigated in the context of the λ 3 -iodane-mediated dearomative spirolactonization of naphthols. The scope and limitations of this methodology were evaluated using various substrates, which were converted into spirolactones in good yields and with enantiomeric excesses up to 58%. [ABSTRACT FROM AUTHOR]
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- 2017
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132. Photochemistry of 1- and 2-Naphthols and Their Water Clusters: The Role of 1ππ*(La) Mediated Hydrogen Transfer to Carbon Atoms.
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Novak, Jurica, Prlj, Antonio, Basarić, Nikola, Corminboeuf, Clémence, and Došlić, Nađa
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WATER clusters , *PHOTOCHEMISTRY , *HYDROGEN transfer reactions , *COMPUTATIONAL chemistry , *ACTIVATION (Chemistry) - Abstract
The computational analysis of the isomer- and conformer-dependent photochemistry of 1- and 2-naphthols and their microsolvated water clusters is motivated by their very different excited state reactivities. We present evidence that 1- and 2-naphthol follow distinct excited state deactivation pathways. The deactivation of 2-naphthols, 2-naphthol water clusters, as well as of the anti conformer of 1-naphthol is mediated by the optically dark 1πσ* state. The dynamics of the 1πσ* surface leads to the homolytic cleavage of the OH bond. On the contrary, the excited state deactivation of syn 1-naphthol and 1-naphthol water clusters follows an uncommon reaction pathway. Upon excitation to the bright 1ππ*(La) state, a highly specific excited state hydrogen transfer (ESHT) to carbon atoms C8 and C5 takes place, yielding 1,8- and 1,5-naphthoquinone methides. The ESHT pathway arises from the intrinsic electronic properties of the 1ππ*(La) state of 1-naphthols. [ABSTRACT FROM AUTHOR]
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- 2017
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133. Enzymatic glucosylation of unnatural naphthols by a promiscuous glycosyltransferase from Aloe arborescens.
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Xie, Kebo, Zhang, Yujiao, Chen, Ridao, Chen, Dawei, Yang, Lin, Liu, Xia, and Dai, Jungui
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GLYCOSYLTRANSFERASES , *NAPHTHOL , *GLUCOSIDES , *BIOACTIVE compounds , *CHEMICAL synthesis - Abstract
Enzymatic glucosylation of unnatural products by natural glycosyltransferases (GTs) has great potential in creating novel and bioactive glucosides. A new GT (AaGT3) from Aloe arborescens exhibited catalytic promiscuity and high efficiency to diverse unnatural naphthols. By combing the substrate flexibility and catalytic reversibility of AaGT3, a cost-effective enzymatic approach to novel and bioactive unnatural glucosides was established. These studies indicate the significant potential of promiscuous natural GTs in synthesis of unnatural bioactive glucosides in drug discovery. [ABSTRACT FROM AUTHOR]
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- 2017
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134. Base-Promoted Three-Component One-Pot Approach to 3-(α,α-Diarylmethyl)indoles via Arylation of 3-Indolylalcohols.
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Deb, Mohit L., Borpatra, Paran J., Saikia, Prakash J., and Baruah, Pranjal K.
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DIARYL compounds , *METHYL groups , *INDOLE compounds , *ARYLATION , *NAPHTHOL - Abstract
A base-promoted 3-component one-pot approach to 3-(α,α- diarylmethyl)indoles via arylation of in situ generated 3-indolylalcohols in ethanol–water solvent system is reported. Use of acid catalysts or neutral organocatalysts does not offer the desired product, but furnish bis(indolyl)methanes instead. Electron-rich aromatics such as naphthols and phenols are preferably employed for arylation. The atom economy, use of green solvent, and the multicomponent strategy are the notable features of the reaction. [ABSTRACT FROM AUTHOR]
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- 2017
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135. Electro-organic Synthesis as a Sustainable Alternative for Dehydrogenative Cross-Coupling of Phenols and Naphthols.
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Riehl, Barbara, Dyballa, Katrin M., Franke, Robert, and Waldvogel, Siegfried R.
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- *
ORGANIC electrochemistry , *COUPLING reactions (Chemistry) , *PHENOLS , *NAPHTHOL , *ALCOHOLS (Chemical class) , *ELECTRICITY - Abstract
The dehydrogenative cross-coupling of phenols and naphthols can be achieved by several oxidative methods. However, the key is the use of fluorinated alcohols such as 1,1,1,3,3,3-hexafluoroisopropanol. The direct application of electricity represents an alternative synthetic approach, which is superior to other oxidizers (e.g., peroxides). The method is sustainable, inherently safe, and easily scalable. [ABSTRACT FROM AUTHOR]
- Published
- 2017
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136. Discovery of Naphthol Tetramers from Endolichenic Fungus Daldinia childiae 047219 Based on MS/MS Molecular Networking.
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Kim J, He MT, Hur JS, Lee JW, Kang KB, Kang KS, and Shim SH
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- Naphthols, Tandem Mass Spectrometry, Ascomycota, Xylariales
- Abstract
Feature-based molecular networking analysis suggested the presence of naphthol tetramers in Daldinia childae 047219, the same species but a different strain from one used previously for the discovery of naphthol trimers promoting adiponectin synthesis. The new tetramers were composed of 5-methoxy-4-naphthol, each of which was connected to one another in various positions. Targeted isolation afforded six previously unreported naphthol tetramers ( 1 - 6 ) together with 13 known polyketides ( 7 - 19 ) including naphthol monomers, dimers, and trimers. Structures of the isolated compounds were established by using NMR and mass spectroscopic analysis. Nodulisporin A ( 13 ), nodulisporin B ( 14 ), and 1,1',3',3″-ternaphthalene-5,5',5″-trimethoxy-4,4',4″-triol ( 16 ) demonstrated anti-inflammatory activities against NO production, but the new compounds were less active.
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- 2023
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137. A basidomycetous hydroxynaphthalene-prenylating enzyme exhibits promiscuity toward prenyl donors.
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Martin A, Dierlamm N, Zocher G, and Li SM
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- Naphthols, Prenylation, Substrate Specificity, Dimethylallyltranstransferase metabolism
- Abstract
The fungal prenyltransferase ShPT from Stereum hirsutum was believed to prenylate 4-hydroxybenzyl alcohol and thereby be involved in the vibralactone biosynthesis. In this study, we demonstrate that hydroxynaphthalenes instead of benzyl alcohol or aldehyde were accepted by ShPT for regular C-prenylation in the presence of both dimethylallyl and geranyl diphosphate. Although the natural substrate of ShPT remains unknown, our results provide one additional prenyltransferase from basidiomycetes, which are less studied, in comparison to those from other sources. Furthermore, this study expands the chemical toolbox for regioselective production of prenylated naphthalene derivatives. KEY POINTS: •Basidiomycetous prenyltransferase •Biochemical characterization •A DMATS prenyltransferase prenylating hydroxynaphthalene derivatives., (© 2023. The Author(s).)
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- 2023
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138. Catalytic Asymmetric Synthesis of Aza-Quaternary Carbon Cyclohexadieneones Enabled by Aminative Dearomatization of Phenols.
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Chen Y, Jia SK, Xiao X, Wang MC, Huang L, and Mei GJ
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- Stereoisomerism, Naphthols, Catalysis, Phenols, Indoles
- Abstract
Reported herein is the catalytic asymmetric aminative dearomatization reaction of common phenols. As opposed to the well-studied indoles and naphthols, phenols are supposed to be challenging substrates for catalytic asymmetric dearomatization reactions in terms of their strong aromaticity and regioselectivity issues. Under the catalysis of a chiral phosphoric acid, the C4-regiospecific aminative dearomatization of phenols with azodicarboxylates readily occurred at ambient temperature, delivering an array of biologically and synthetically important aza-quaternary carbon cyclohexadieneones in good yields and with excellent enantioselectivities (29 examples, up to 98% yield, and >99% ee).
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- 2023
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139. Cascade reaction of 2,3-naphthalenediol with benzene in the presence of aluminum halides.
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Zhu, Zhongwei, Salnikov, George E., and Koltunov, Konstantin Yu.
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CASCADES (Fluid dynamics) , *NAPHTHALENE , *BENZENE , *ALUMINUM halides , *CYCLOHEPTANE - Abstract
Graphical abstract Highlights • 2,3-Naphthalenediol undergoes superelectrophilic activation in the presence of AlCl 3 or AlBr 3. • This provides its cascade reaction with benzene at mild conditions. • The intermediate reaction product is 4-((3-phenyl-1 H -inden-1-yl)methyl)benzene-1,2-diol. • The final reaction product is 5,10-methano-5-phenyldibenzo[ a , d ]cycloheptane-2,3-diol. • The last compound can be of interest to clinical trials as anti-breast cancer agent. Abstract 2,3-Naphthalenediol on superelectrophilic activation with aluminium halides smoothly reacts with benzene to give 4-((3-phenyl-1 H -inden-1-yl)methyl)benzene-1,2-diol, which in turn undergoes intramolecular cyclization to form 5,10-methano-5-phenyldibenzo[ a , d ]cycloheptane-2,3-diol. The mechanistic aspects of these unusual transformations are discussed. [ABSTRACT FROM AUTHOR]
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- 2019
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140. Atropselective Hydrolysis of Chiral Binol-Phosphate Esters Catalyzed by the Phosphotriesterase from Sphingobium sp. TCM1
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Frank M. Raushel, Tamari Narindoshvili, and Dao Feng Xiang
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Hydrolysis ,Stereoisomerism ,Naphthols ,Phosphate ,Biochemistry ,Chemical synthesis ,Article ,Catalysis ,Phosphates ,Substrate Specificity ,Sphingomonadaceae ,Kinetics ,chemistry.chemical_compound ,Phosphoric Triester Hydrolases ,Bacterial Proteins ,chemistry ,Asymmetric carbon ,Organic chemistry ,Stereoselectivity ,Enantiomer ,Triphenyl phosphate - Abstract
The phosphotriesterase from Sphingobium sp. TCM1 (Sb-PTE) is notable for its ability to hydrolyze a broad spectrum of organophosphate triesters, including organophosphorus flame retardants and plasticizers such as triphenyl phosphate and tris(2-chloroethyl) phosphate that are not substrates for other enzymes. This enzyme is also capable of hydrolyzing any one of the three ester groups attached to the central phosphorus core. The enantiomeric isomers of 1,1′-bi-2-naphthol (BINOL) have become among the most widely used chiral auxiliaries for the chemical synthesis of chiral carbon centers. PTE was tested for its ability to hydrolyze a series of biaryl phosphate esters, including mono- and bis-phosphorylated BINOL-derivatives and cyclic phosphate triesters. Sb-PTE was shown to be able to catalyze the hydrolysis of the chiral phosphate triesters with significant stereoselectivity. The catalytic efficiency, k(cat)/K(m), of Sb-PTE toward the test phosphate triesters ranged from ~10 M(−1) s(−1) to 10(5) M(−1) s(−1). The product ratios and stereoselectivities were determined for four pairs of phosphorylated BINOL derivatives.
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- 2020
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141. Phytohormones and volatile organic compounds, like geosmin, in the ectomycorrhiza of Tricholoma vaccinum and Norway spruce (Picea abies)
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Wilhelm Boland, Anja David, Mario Kallenbach, Erika Kothe, Maritta Kunert, Katharina Wagner, Oluwatosin Abdulsalam, Katrin Krause, and Sophia Wirth
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0106 biological sciences ,Germacradienol synthase ,Mycorrhizosphere ,Plant Science ,Naphthols ,Biology ,01 natural sciences ,03 medical and health sciences ,chemistry.chemical_compound ,Plant Growth Regulators ,Auxin ,Mycorrhizae ,Botany ,Genetics ,Mycorrhiza ,Picea ,Molecular Biology ,Abscisic acid ,Ecology, Evolution, Behavior and Systematics ,030304 developmental biology ,Geosmin ,chemistry.chemical_classification ,0303 health sciences ,Volatile Organic Compounds ,Tricholoma vaccinum ,Norway ,fungi ,Tricholoma ,General Medicine ,biology.organism_classification ,Ectomycorrhiza ,Phytohormones ,chemistry ,Norway spruce ,Original Article ,Agaricales ,Abies ,Salicylic acid ,010606 plant biology & botany - Abstract
The ectomycorrhizospheric habitat contains a diverse pool of organisms, including the host plant, mycorrhizal fungi, and other rhizospheric microorganisms. Different signaling molecules may influence the ectomycorrhizal symbiosis. Here, we investigated the potential of the basidiomyceteTricholoma vaccinumto produce communication molecules for the interaction with its coniferous host, Norway spruce (Picea abies). We focused on the production of volatile organic compounds and phytohormones in axenicT. vaccinumcultures, identified the potential biosynthesis genes, and investigated their expression by RNA-Seq analyses.T. vaccinumreleased volatiles not usually associated with fungi, like limonene and β-barbatene, and geosmin. Using stable isotope labeling, the biosynthesis of geosmin was elucidated. The geosmin biosynthesis geneges1ofT. vaccinumwas identified, and up-regulation was scored during mycorrhiza, while a different regulation was seen with mycorrhizosphere bacteria. The fungus also released the volatile phytohormone ethylene and excreted salicylic and abscisic acid as well as jasmonates into the medium. The tree excreted the auxin, indole-3-acetic acid, and its biosynthesis intermediate, indole-3-acetamide, as well as salicylic acid with its root exudates. These compounds could be shown for the first time in exudates as well as in soil of a natural ectomycorrhizospheric habitat. The effects of phytohormones present in the mycorrhizosphere on hyphal branching ofT. vaccinumwere assessed. Salicylic and abscisic acid changed hyphal branching in a concentration-dependent manner. Since extensive branching is important for mycorrhiza establishment, a well-balanced level of mycorrhizospheric phytohormones is necessary. The regulation thus can be expected to contribute to an interkingdom language.
- Published
- 2020
142. Construction of an artificial system for ambrein biosynthesis and investigation of some biological activities of ambrein
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Yuko Tajima, Yoshito Kakihara, Yukina Kawagoe, Kotone Okuno, Yota Yamabe, Kanako Chikaoka, Daijiro Ueda, Tadasu K. Yamada, Mao Inoue, Tsutomu Sato, and Takashi Hara
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0301 basic medicine ,Metabolite ,Osteoclasts ,lcsh:Medicine ,Ambergris ,Apoptosis ,Naphthols ,010402 general chemistry ,01 natural sciences ,Biochemistry ,Article ,Cell Line ,03 medical and health sciences ,chemistry.chemical_compound ,Biosynthesis ,Animals ,Humans ,lcsh:Science ,Ambrein ,Volatile Organic Compounds ,Multidisciplinary ,Amyloid beta-Peptides ,Sperm Whale ,lcsh:R ,Cell Differentiation ,Chemical biology ,Triterpenes ,0104 chemical sciences ,030104 developmental biology ,chemistry ,Odor ,Photooxidative degradation ,lcsh:Q - Abstract
Ambergris, a sperm whale metabolite, has long been used as a fragrance and traditional medication, but it is now rarely available. The odor components of ambergris result from the photooxidative degradation of the major component, ambrein. The pharmacological activities of ambergris have also been attributed to ambrein. However, efficient production of ambrein and odor compounds has not been achieved. Here, we constructed a system for the synthesis of ambrein and odor components. First, we created a new triterpene synthase, “ambrein synthase,” for mass production of ambrein by redesigning a bacterial enzyme. The ambrein yields were approximately 20 times greater than those reported previously. Next, an efficient photooxidative conversion system from ambrein to a range of volatiles of ambergris was established. The yield of volatiles was 8–15%. Finally, two biological activities, promotion of osteoclast differentiation and prevention of amyloid β-induced apoptosis, were discovered using the synthesized ambrein.
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- 2020
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143. Statistical approach to evaluate effect of temperature and moisture content on the production of antioxidant naphtho-gamma-pyrones and hydroxycinnamic acids by Aspergillus tubingensis in solid-state fermentation
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Catherine Rébufa, Rayhane Hamrouni, Sevastianos Roussos, Isabelle Bombarda, Quentin Carboué, Institut méditerranéen de biodiversité et d'écologie marine et continentale (IMBE), and Avignon Université (AU)-Aix Marseille Université (AMU)-Institut de recherche pour le développement [IRD] : UMR237-Centre National de la Recherche Scientifique (CNRS)
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0106 biological sciences ,Dihydropyridines ,Coumaric Acids ,Principal component analysis ,Hydroxycinnamic acids ,Bioengineering ,Naphthols ,01 natural sciences ,Antioxidants ,Naphtho-gamma-pyrones ,chemistry.chemical_compound ,Solid-state fermentation ,Ergosterol ,010608 biotechnology ,[CHIM]Chemical Sciences ,Food science ,Chromatography, High Pressure Liquid ,2. Zero hunger ,chemistry.chemical_classification ,Models, Statistical ,Moisture ,Bran ,010405 organic chemistry ,Chemistry ,Temperature ,food and beverages ,General Medicine ,Plants ,Hydroxycinnamic acid ,0104 chemical sciences ,Kinetics ,Aspergillus ,Aspergillus tubingensis ,Pyrones ,Fermentation ,Vine shoots ,Industrial and production engineering ,Heterocyclic Compounds, 3-Ring ,Biotechnology - Abstract
International audience; Non-ochratoxigenic Aspergillus tubingensis G131 is a filamentous fungus that can produce naphtho-gamma-pyrones (NγPs), polyketide pigments that exhibit interesting antioxidant properties. This study aims to investigate the effect of two critical parameters, temperature and moisture content on the fungus grown in solid-state fermentation using agricultural by-products (vine shoots and wheat bran) as sole medium. From the kinetic productions of secondary metabolites NγPs (asperpyrone E, dianhydroaurasperone C, fonsecin, fonsecin B and ustilaginoidin A), alkaloids (nigragilin and aspernigrin A), degradation products from the solid medium (β-d-glucose, p-coumaric acid and trans-ethyl ferulate), ergosterol and conidia obtained for different temperatures and moisture contents, a principal component analysis (PCA) was carried out to highlight the production patterns of these compounds. This approach allowed us to determine that fonsecin, the compound of higher interestexhibiting the most interesting antiradical potential-is particularly more produced at 25 °C and 66% of moisture content. This study underlines the importance of temperature and moisture content on naphtho-gamma-pyrones and hydroxycinnamic acid production using solid-state fermentation and contributes to the development of agroindustrial by-product valorization.
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- 2020
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144. Luminescent Chemosensor Based on Ru(II) Bipyridine Complex for Detection of Sudan I through Inner Filter Effect
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Qijun Song, Sujitraj Sheth, and Mengyuan Li
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Sudan I ,Analyte ,Sociology and Political Science ,Pyridines ,Clinical Biochemistry ,Inorganic chemistry ,Naphthols ,010402 general chemistry ,01 natural sciences ,Biochemistry ,Chemistry Techniques, Analytical ,Ruthenium ,chemistry.chemical_compound ,Bipyridine ,Coordination Complexes ,Limit of Detection ,Spectroscopy ,Detection limit ,Quenching (fluorescence) ,Ethanol ,010405 organic chemistry ,0104 chemical sciences ,Clinical Psychology ,chemistry ,Luminescent Measurements ,Luminophore ,Filter effect ,Capsicum ,Luminescence ,Law ,Social Sciences (miscellaneous) - Abstract
Presence of Sudan I in food stuff can be problematic and need to be checked in order to protect our health from possible carcinogen. Therefore, it is essential to detect Sudan I by efficient, rapid and reliable method. In this work, we have designed a Ru(II) polypyridyl complex, [Ru(bpy)2(CIP)]2+ probe for the selective and sensitive detection of Sudan I. Upon addition of Sudan I to the solution of [Ru(bpy)2(CIP)]2+ in ethanol, the luminescence quenched rapidly, and linear concentration range with analyte has been obtained from 0.8 to 100 μM with the limit of detection as low as 0.26 μM (S/N = 3). The effective luminescence quenching was resulted due to the inner filter effect (IFE) between luminophore, [Ru(bpy)2(CIP)]2+ and quencher, Sudan I. Our spectroscopic study was essentially provided sufficient analytical evidences in order to prove occurrence of IFE mechanism. As there were no interferences observed in luminescence measurement from the other substances the present probe has been successfully applied for the detection of Sudan I in commercial chili powder sample, making the probe suitable for practical usage.
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- 2020
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145. NaSH increases SIRT1 activity and autophagy flux through sulfhydration to protect SH-SY5Y cells induced by MPP~+
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Lan Ma, Jing Li, Liping Wang, Shuhu Zhang, Mei Li, Qiang Gao, and Cui Wang
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0301 basic medicine ,1-Methyl-4-phenylpyridinium ,Mating type ,SH-SY5Y ,Hydrogen sulfide ,Naphthols ,Biology ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Sirtuin 1 ,Cell Line, Tumor ,Autophagy ,Animals ,Humans ,Hydrogen Sulfide ,Molecular Biology ,Potential effect ,Parkinson Disease ,Cell Biology ,equipment and supplies ,Cell biology ,Mice, Inbred C57BL ,Neuroprotective Agents ,030104 developmental biology ,chemistry ,030220 oncology & carcinogenesis ,Benzamides ,Flux (metabolism) ,Research Paper ,Developmental Biology - Abstract
Parkinson’s disease (PD) is one of the most prevailing aging diseases around the world. The present study was to investigate the potential effect of hydrogen sulfide (H(2)S) and silent mating type information regulation 2 homolog 1 (SIRT1) in MPP~+ induced SH-SY5Y cells and its underlying mechanisms in PD. SH-SY5Y cells were induced by MPP~+ and treated with the H(2)S donor NaHS to detect the effect of H(2)S on the molecular behaviors of MPP~+ induced SH-SY5Y cells. NaHS reduced the apoptosis rate and expressions of MDA, 4-HNE and p62, while increased cell viability, autophagy flux and expressions of LC3 II/I and Beclin1 in MPP~+ induced SH-SY5Y cells. Then, levels of autophagy-related proteins and inflammation-related proteins (TNF-α, IL-Iβ) were detected, indicating that Chloroquine and Sirtinol reversed the protective effect of H(2)S on SH-SY5Y cells induced by MPP~+. We further explored the particular function of H(2)S, SH-SY5Y cells treated with MPP~+, NaHS chloroquine, and SIRT1 inhibitor (Sirtinol). The results showed that H(2)S increased SIRT1 expression and sulfhydration. Finally, a PD mouse model verified the above results. In a word, H(2)S ameliorated SIRT1 activity through acceleration of SIRT1 sulfhydration to increase the autophagy flux and attenuate damage of SH-SY5Y cells induced by MPP~+. H(2)S and SIRT1 activator might be a target in the treatment of PD patients.
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- 2020
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146. Characterization of the Partition Rate of 2-Naphthol (NAP) and Ritonavir (RTV) Across the Water-Octanol Interface and the Influence of Common Pharmaceutical Excipients
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Weili Wang, Socrates Vela, and Ping Gao
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Octanol ,Octanols ,Pharmaceutical Science ,Naphthols ,02 engineering and technology ,030226 pharmacology & pharmacy ,Excipients ,03 medical and health sciences ,chemistry.chemical_compound ,symbols.namesake ,0302 clinical medicine ,Gibbs isotherm ,PEG ratio ,chemistry.chemical_classification ,Ritonavir ,Aqueous solution ,Water ,Polymer ,021001 nanoscience & nanotechnology ,Partition coefficient ,Nap ,Solubility ,chemistry ,Polymerization ,symbols ,0210 nano-technology ,Nuclear chemistry - Abstract
The partition rate of 2 model compounds, 2-naphthol (NAP) and ritonavir (RTV), across the water-octanol (W/O) interface was determined from aqueous solutions with and without the presence of a variety of common pharmaceutical excipients. The NAP molecule was present as either a unionized species in the phosphate buffer solution or as an anion in 0.01 M NaOH solution while RTV was present as dications in 0.1 M HCl. Excipients examined include different type of polymers (e.g., PVP-VA, HPMC, HPMCAS, PVP, PEG 8000), small molecules (e.g., glucose, lactose, maltoheptaose), and surfactants (e.g., Tween 80 and SDS). A noticeable to significant reduction of the partition rate of both NAP and RTV across the W/O interface was observed with aqueous media containing 0.01–0.1 μg/mL polymers including PVP-VA, HPMC, and HPMCAS. Reduction of NAP and RTV partition rate associated with such extremely low concentration of polymers in the aqueous media affirms the presence of a surface excess of adsorbed excipients at the W/O interface. Pi values of NAP and RTV across the W/O interface are found to be sensitive to (1) the molecule surface area, molecular weight and the degree of the polymerization of these pharmaceutical excipients, and (2) the ionization state of the model compound.
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- 2020
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147. Naphthylisoquinoline alkaloids, validated as hit multistage antiplasmodial natural products
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William Shamburger, Gerhard Bringmann, Timothy J. Egan, Janette Reader, Vinesh Maharaj, Lyn-Marie Birkholtz, Mariëtte van der Watt, Phanankosi Moyo, and Ana Carolina C. de Sousa
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0301 basic medicine ,Drug ,Erythrocytes ,media_common.quotation_subject ,030231 tropical medicine ,Plasmodium falciparum ,Naphthols ,Pharmacology ,Article ,lcsh:Infectious and parasitic diseases ,03 medical and health sciences ,Antimalarials ,Mice ,0302 clinical medicine ,Alkaloids ,Multistage active antimalarial drug candidates ,Chloroquine ,medicine ,Gametocyte ,Animals ,Humans ,Pharmacology (medical) ,lcsh:RC109-216 ,IC50 ,media_common ,Biological Products ,Life Cycle Stages ,Natural products ,Hit validation ,biology ,Chemistry ,Plant Extracts ,Naphthylisoquinoline alkaloids ,biology.organism_classification ,medicine.disease ,Isoquinolines ,In vitro ,Rats ,Malaria ,030104 developmental biology ,Infectious Diseases ,Microsome ,Parasitology ,medicine.drug - Abstract
The discovery and development of multistage antimalarial drugs targeting intra-erythrocytic asexual and sexual Plasmodium falciparum parasites is of utmost importance to achieve the ambitious goal of malaria elimination. Here, we report the validation of naphthylisoquinoline (NIQ) alkaloids and their synthetic analogues as multistage active antimalarial drug candidates. A total of 30 compounds were tested, of which 17 exhibited IC50 values 10. The tested compounds showed activity in vitro against both early- and late-stage P. falciparum gametocytes while blocking male gamete formation (>70% inhibition of exflagellation at 2 μM). Additionally, five selected compounds were found to have good solubility (≥170 μM in PBS at pH 6.5), while metabolic stability towards human, mouse, and rat microsomes ranged from >90% to >7% after 30 min. Dioncophylline C (2a) emerged as a front runner from the study, displaying activity against both asexual parasites and gametocytes, a lack of cross-resistance to chloroquine, good solubility, and microsomal stability. Overall, this is the first report on the multistage activity of NIQs and their synthetic analogues including gametocytocidal and gametocidal effects induced by this class of compounds., Graphical abstract Image 1, Highlights • Naphthylisoquinolines (NIQs) validated as antimalarial hit candidates. • First report on transmission-blocking properties of NIQs and analogues. • 15 compounds active across 9 P. falciparum strains, with acceptable RI 10. • 5 compounds show good solubility and microsomal stability. • Dioncophylline C is the frontrunner antimalarial candidate with multistage activity.
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- 2020
148. Oxygenated Geosmins and Plant-like Eudesmanes from a Bacterial Mangrove Endophyte
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Ling Ding and Christian Hertweck
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Metabolite ,Pharmaceutical Science ,Microbial Sensitivity Tests ,Naphthols ,Streptomyces ,Endophyte ,Analytical Chemistry ,Terpene ,chemistry.chemical_compound ,Bioremediation ,Drug Discovery ,Botany ,Endophytes ,Sesquiterpenes, Eudesmane ,Pharmacology ,biology ,Chemistry ,Spectrum Analysis ,Organic Chemistry ,biology.organism_classification ,Antimicrobial ,Geosmin ,Anti-Bacterial Agents ,Oxygen ,Complementary and alternative medicine ,Rhizophoraceae ,Molecular Medicine ,Bacteria - Abstract
Geosmin (1) is a microbial terpene metabolite that is responsible for the typical smell of soil and causes an off-odor of food and water. Eudesmane sesquiterpenes are commonly found in plant essential oils. Here we describe the discovery of four geosmin-type metabolites, 7R-hydroxygeosmin (2), 3-oxogeosmin (3), 2R-hydroxy-7-oxogeosmin (4), 5-deoxy-7β,9β-dihydroxygeosmin (5), the plant-like eudesmanes 4β,10α-eudesmane-5β,11-diol (6) and (1S,5S,6S,7S,10S)-10α-eudesm-4(15)-ene-1α,6α-diol (7), and the known 1(10)E,5E-germacradiene-2,11-diol (8) from a bacterial endophyte (Streptomyces sp. JMRC:ST027706) of the mangrove plant Bruguiera gymnorrhiza. By means of NMR, MS, and ECD spectroscopy, all chemical structures as well as the absolute configurations for the new compounds were elucidated. Compounds 2-5 represent the first geosmin-related metabolites directly as bacterial natural products. The plant-derived eudesmane-5β,11-diol (6) and (1S,5S,6S,7S,10S)-10α-eudesm-4(15)-ene-1α,6α-diol (7) are also now reported as bacterial products. The broad antimicrobial activities of 6 against a suite of fungal and bacterial pathogens including methicillin-resistant Staphylococcus aureus suggest that this terpene could be an important active principle of the medicinal plant Cymbopogon distans. The discovery of geosmin metabolites from one actinomycete indicated that these bacteria could possess enzymes for modifying geosmin and offer a possibility for bioremediation.
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- 2020
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149. CREB activity is required for mTORC1 signaling-induced primordial follicle activation in mice
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Chunyu Zhang, Jia Li, Meijia Zhang, Yu Zhang, Nana Zheng, Jing Yang, Guoliang Xia, and Biao Li
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Male ,0301 basic medicine ,Vanadium Compounds ,Histology ,Apoptosis ,Naphthols ,mTORC1 ,Mechanistic Target of Rapamycin Complex 1 ,CREB ,Tissue Culture Techniques ,Mice ,03 medical and health sciences ,Ovarian Follicle ,Animals ,Phosphorylation ,Cyclic AMP Response Element-Binding Protein ,Molecular Biology ,Cell Proliferation ,Mice, Inbred ICR ,Stem Cell Factor ,Gene knockdown ,030102 biochemistry & molecular biology ,biology ,Chemistry ,Kinase ,Cell growth ,Cell Biology ,Organophosphates ,Cell biology ,Medical Laboratory Technology ,030104 developmental biology ,biology.protein ,Female ,Phosphatidylinositol 3-kinase signaling ,Folliculogenesis ,Signal Transduction - Abstract
In mammals, progressive activation of primordial follicles is essential for maintenance of the reproductive lifespan. Several reports have demonstrated that mitogen-activated protein kinases 3 and 1 (MAPK3/1)-mammalian target of rapamycin complex 1 (mTORC1) signaling in pre-granulosa cells promotes primordial follicle activation by increasing KIT ligand (KITL) expression and then stimulating phosphatidylinositol 3 kinase signaling in oocytes. However, the mechanism of mTORC1 signaling in the promotion of KITL expression is unclear. Immunofluorescence staining results showed that phosphorylated cyclic AMP response element-binding protein (CREB) was mainly expressed in pre-granulosa cells. The CREB inhibitor KG-501 and CREB knockdown by Creb siRNA significantly suppressed primordial follicle activation, reduced pre-granulosa cell proliferation and dramatically increased oocyte apoptosis. Western blotting results demonstrated that both the MAPK3/1 inhibitor U0126 and mTORC1 inhibitor rapamycin significantly decreased the levels of phosphorylated CREB, indicating that MAPK3/1-mTORC1 signaling is required for CREB activation. Furthermore, CREB could bind to the Kitl promoter region, and KG-501 significantly decreased the expression levels of KITL. In addition, KG-501 and CREB knockdown significantly decreased the levels of phosphorylated Akt, leading to a reduced number of oocytes with Foxo3a nuclear export. KG-501 also inhibited bpV (HOpic)-stimulated primordial follicle activation. Taken together, the results show that CREB is required for MAPK3/1-mTORC1 signaling-promoted KITL expression followed by the activation of primordial follicles.
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- 2020
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150. The Architecture of Metabolism Maximizes Biosynthetic Diversity in the Largest Class of Fungi
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Joseph W. Spatafora, Emile Gluck-Thaler, Sajeet Haridas, Manfred Binder, Kathryn E. Bushley, Igor V. Grigoriev, Jason C. Slot, Pedro W. Crous, Westerdijk Fungal Biodiversity Institute - Evolutionary Phytopathology, Westerdijk Fungal Biodiversity Institute, and Townsend, Jeffrey
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0106 biological sciences ,media_common.quotation_subject ,Naphthols ,Biology ,Secondary metabolite ,AcademicSubjects/SCI01180 ,01 natural sciences ,Genome ,gene cluster ,03 medical and health sciences ,Ascomycota ,Gene cluster ,Genetics ,medicine ,Gene Regulatory Networks ,Ecosystem diversity ,Molecular Biology ,Gene ,Ecology, Evolution, Behavior and Systematics ,Discoveries ,media_common ,030304 developmental biology ,Melanins ,Evolutionary Biology ,0303 health sciences ,Repertoire ,AcademicSubjects/SCI01130 ,chemical ecology ,Molecular Sequence Annotation ,Dothideomycetes ,biology.organism_classification ,Biosynthetic Pathways ,Metabolic pathway ,Evolutionary biology ,Multigene Family ,Identification (biology) ,Biochemistry and Cell Biology ,fungi ,human activities ,metabolism ,Diversity (politics) ,010606 plant biology & botany ,medicine.drug - Abstract
BackgroundEcological diversity in fungi is largely defined by metabolic traits, including the ability to produce secondary or “specialized” metabolites (SMs) that mediate interactions with other organisms. Fungal SM pathways are frequently encoded in biosynthetic gene clusters (BGCs), which facilitate the identification and characterization of metabolic pathways. Variation in BGC composition reflects the diversity of their SM products. Recent studies have documented surprising diversity of BGC repertoires among isolates of the same fungal species, yet little is known about how this population-level variation is inherited across macroevolutionary timescales.ResultsHere, we applied a novel linkage-based algorithm to reveal previously unexplored dimensions of diversity in BGC composition, distribution, and repertoire across 101 species of Dothideomycetes, which are considered to be the most phylogenetically diverse class of fungi and are known to produce many SMs. We predicted both complementary and overlapping sets of clustered genes compared with existing methods and identified novel gene pairs that associate with known secondary metabolite genes. We found that variation in BGC repertoires is due to non-overlapping BGC combinations and that several BGCs have biased ecological distributions, consistent with niche-specific selection. We observed that total BGC diversity scales linearly with increasing repertoire size, suggesting that secondary metabolites have little structural redundancy in individual fungi.ConclusionsWe project that there is substantial unsampled BGC diversity across specific families of Dothideomycetes, which will provide a roadmap for future sampling efforts. Our approach and findings lend new insight into how BGC diversity is generated and maintained across an entire fungal taxonomic class.
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- 2020
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