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Imine-linked covalent organic frameworks (COFs) are garnering substantial interest in resistive random-access memory, attributed to their superior crystallinity, excellent chemical and thermal stability, and modifiable molecular structures. However, the development of high-performance COF-based memristors impeded by challenges such as low conjugation degree of imine bonds and poor electron delocalization ability. Herein, we report a protonation strategy to modify the imine bonds of donor-acceptor (D-A) type COFs. This modification significantly enhances the electron delocalization capability of imine bonds, lowers the energy barriers for electron injection from electrodes, and stabilizes the conductive charge transfer state, thus markedly improving device performance. The protonated COF-BTT-BPy and COF-BTT-TAPT thin films-based memristors show remarkable device performance with a high ON/OFF current ratio of 105, a low driving voltage, and outstanding endurance exceeding 600 and 1300 cycles, respectively, which is nearly twice the durability of analogous non-protonated COFs-based memristors. Notably, the protonated COF-BTT-TAPT-based memristor exhibit the highest number of cycles reported at present. This work not only unprecedentedly enhances the performance of COF-based memristors, but also provides a universal and promising approach for the molecular design and potential application of D-A type imine-linked COFs.
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OBJECTIVES: To evaluate the effectiveness and safety of Qishen Yiqi Dripping Pill (QSYQ) in patients with acute coronary syndrome (ACS) after percutaneous coronary intervention (PCI). METHODS: This multicentre prospective cohort study was conducted at 40 centers in China. Patients with ACS after PCI entered either the QSYQ or Western medicine (WM) groups naturally based on whether they had received QSYQ before enrollment. QSYQ group received QSYQ (0.52 g, 3 times a day for 12 months) in addition to WM. The primary endpoint included cardiac death, non-fatal myocardial infarction, and urgent revascularization. The secondary endpoint included rehospitalization due to ACS, heart failure, stroke, and other thrombotic events. Quality of life was assessed by the Seattle Angina Questionnaire (SAQ). RESULTS: A total of 936 patients completed follow-up of the primary endpoint from February 2012 to December 2018. Overall, 487 patients received QSYQ and WM. During a median follow-up of 566 days (inter quartile range, IQR, 517-602), the primary endpoint occurred in 46 (9.45%) and 65 (14.48%) patients in QSYQ and WM groups respectively [adjusted hazard ratio (HR) 0.60, 95% confidence interval (CI) 0.41-0.90; P=0.013]. The secondary endpoint occurred in 61 (12.53%) and 74 (16.48%) patients in QSYQ and WM groups, respectively (adjusted HR 0.76, 95% CI 0.53-1.09; P=0.136). In sensitivity analysis, the results still demonstrated that WM combined with QSYQ reduced the risk of the primary endpoint (HR 0.67, 95% CI 0.46-0.98; P=0.039). Moreover, QSYQ improved the disease perception domain of the SAQ (P<0.05). CONCLUSION: In patients with ACS after PCI, QSYQ combined with WM reduced the incidence of the primary endpoint. These findings provide a promising option for managing ACS after PCI and suggest the potential treatment for reducing the risk of primary endpoint included cardiac death, non-fatal myocardial infarction, and urgent revascularization through intermittent administration of QSYQ (Registration No. ChiCTR-OOC-14005552).
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Crosstalk-oriented chemical evolution of natural products (NPs) is an efficacious strategy for generating novel skeletons through coupling reactions between NP fragments. In this study, two NOD-like receptor protein 3 (NLRP3) inflammasome inhibitors, sorbremnoids A and B (1 and 2), with unprecedented chemical architectures were identified from a fungus Penicillium citrinum. Compounds 1 and 2 exemplify rare instances of hybrid NPs formed via a major facilitator superfamily (MFS)-like enzyme by coupling reactive intermediates from two separate biosynthetic gene clusters (BGCs), pcisor and pci56. Both sorbremnoids A and B are NLRP3 inflammasome inhibitors. Sorbremnoid A demonstrated strong inhibition of IL-1ß by directly binding to the NLRP3 protein, inhibiting the assembly and activation of the NLRP3 inflammasome in vitro, with potential application in diabetic refractory wound healing through the suppression of excessive inflammatory responses. This research will inspire the development of anti-NLRP3 inflammasome agents as lead treatments and enhance knowledge pertaining to NPs derived from biosynthetic crosstalk.
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Inflamasomas , Proteína con Dominio Pirina 3 de la Familia NLR , Penicillium , Proteína con Dominio Pirina 3 de la Familia NLR/metabolismo , Proteína con Dominio Pirina 3 de la Familia NLR/antagonistas & inhibidores , Inflamasomas/metabolismo , Inflamasomas/antagonistas & inhibidores , Penicillium/metabolismo , Penicillium/química , Humanos , Vías Biosintéticas/efectos de los fármacos , Interleucina-1beta/metabolismo , Productos Biológicos/química , Productos Biológicos/farmacología , Productos Biológicos/metabolismo , Estructura MolecularRESUMEN
Numerous clinical disorders have been linked to the etiology of dysregulated NLRP3 (NACHT, LRR, and PYD domain-containing protein 3) inflammasome activation. Despite its potential as a pharmacological target, modulation of NLRP3 activity remains challenging. Only a sparse number of compounds have been reported that can modulate NLRP3 and none of them have been developed into a commercially available drug. In this research, we identified three potent NLRP3 inflammasome inhibitors, gymnoasins A-C (1-3), with unprecedented pentacyclic scaffolds, from an Antarctic fungus Pseudogymnoascus sp. HDN17-895, which represent the first naturally occurring naphthopyrone-macrolide hybrids. Additionally, biomimetic synthesis of gymnoasin A (1) was also achieved validating the chemical structure and affording ample amounts of material for exhaustive bioactivity assessments. Biological assays indicated that 1 could significantly inhibited in vitro NLRP3 inflammasome activation and in vivo pro-inflammatory cytokine IL-1ß release, representing a valuable new lead compound for the development of novel therapeutics with the potential to inhibit the NLRP3 inflammasome.
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Phage therapy has shown great promise in the treatment of bacterial infections. However, the effectiveness of phage therapy is compromised by the inevitable emergence of phage-resistant strains. In this study, a phage-resistant carbapenem-resistant Klebsiella pneumoniae strain SWKP1711R, derived from parental carbapenem-resistant K. pneumoniae strain SWKP1711 was identified. The mechanism of bacteriophage resistance in SWKP1711R was investigated and the molecular determinants causing altered growth characteristics, antibiotic resistance, and virulence of SWKP1711R were tested. Compared to SWKP1711, SWKP1711R showed slower growth, smaller colonies, filamentous cells visible under the microscope, reduced production of capsular polysaccharide (CPS) and lipopolysaccharide, and reduced resistance to various antibiotics accompanied by reduced virulence. Adsorption experiments showed that phage vB_kpnM_17-11 lost the ability to adsorb onto SWKP1711R, and the adsorption receptor was identified to be bacterial surface polysaccharides. Genetic variation analysis revealed that, compared to the parental strain, SWKP1711R had only one thymine deletion at position 78 of the open reading frame of the lpcA gene, resulting in a frameshift mutation that caused alteration of the bacterial surface polysaccharide and inhibition of phage adsorption, ultimately leading to phage resistance. Transcriptome analysis and quantitative reverse transcriptase PCR revealed that genes encoding lipopolysaccharide synthesis, ompK35, blaTEM-1, and type II and Hha-TomB toxin-antitoxin systems, were all downregulated in SWKP1711R. Taken together, the evidence presented here indicates that the phenotypic alterations and phage resistance displayed by the mutant may be related to the frameshift mutation of lpcA and altered gene expression. While evolution of phage resistance remains an issue, our study suggests that the reduced antibiotic resistance and virulence of phage-resistant strain derivatives might be beneficial in alleviating the burden caused by multidrug-resistant bacteria.
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Bacteriófagos , Klebsiella pneumoniae , Klebsiella pneumoniae/virología , Klebsiella pneumoniae/efectos de los fármacos , Klebsiella pneumoniae/genética , Virulencia/genética , Bacteriófagos/genética , Bacteriófagos/fisiología , Antibacterianos/farmacología , Carbapenémicos/farmacología , Infecciones por Klebsiella/microbiología , Mutación del Sistema de Lectura , Animales , Enterobacteriaceae Resistentes a los Carbapenémicos/efectos de los fármacos , Enterobacteriaceae Resistentes a los Carbapenémicos/genética , Enterobacteriaceae Resistentes a los Carbapenémicos/virología , Perfilación de la Expresión Génica , Humanos , Polisacáridos Bacterianos/genética , Polisacáridos Bacterianos/metabolismo , Pruebas de Sensibilidad MicrobianaRESUMEN
UbiA-type prenyltransferases (PTases) are significant enzymes that lead to structurally diverse meroterpenoids. Herein, we report the identification and characterization of an undescribed UbiA-type PTase, FtaB, that is responsible for the farnesylation of indole-containing diketopiperazines (DKPs) through genome mining. Heterologous expression of the fta gene cluster and non-native pathways result in the production of a series of new C2-farnesylated DKPs. This study broadens the reaction scope of UbiA-type PTases and expands the chemical diversity of meroterpenoids.
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Dicetopiperazinas , Dimetilaliltranstransferasa , Prenilación , Dimetilaliltranstransferasa/metabolismo , Dimetilaliltranstransferasa/química , Dimetilaliltranstransferasa/genética , Dicetopiperazinas/química , Dicetopiperazinas/metabolismo , Estructura Molecular , Familia de MultigenesRESUMEN
Dimeric indole-containing diketopiperazines (di-DKPs) are a diverse group of natural products produced through cytochrome P450-catalyzed C-C or C-N coupling reactions. The regio- and stereoselectivity of these reactions plays a significant role in the structural diversity of di-DKPs. Despite their pivotal role, the mechanisms governing the selectivity in fungi are not fully understood. Employing bioinformatics analysis and heterologous expression experiments, five undescribed P450 enzymes (AmiP450, AcrP450, AtP450, AcP450, and AtuP450) responsible for the regio- and stereoselective dimerization of diketopiperazines (DKPs) in fungi are identified. The function of these P450s is consistent with phylogenetic analysis, highlighting their dominant role in controlling the dimerization modes. Combinatorial biosynthesis-based pathway reconstitution of non-native gene clusters expands the chemical space of fungal di-DKPs and reveals that the regioselectivity is influenced by the substrate. Furthermore, multiple sequence alignment and molecular docking of these enzymes demonstrate a C-terminal variable region near the substrate tunnel entrance in AtuP450 that is crucial for its regioselectivity. These findings not only reveal the secret of fungal di-DKPs diversity but also deepen understanding of the mechanisms and catalytic specificity involved in P450-catalyzed dimerization reactions.
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Sistema Enzimático del Citocromo P-450 , Dicetopiperazinas , Dimerización , Dicetopiperazinas/metabolismo , Dicetopiperazinas/química , Sistema Enzimático del Citocromo P-450/metabolismo , Sistema Enzimático del Citocromo P-450/genética , Sistema Enzimático del Citocromo P-450/química , Estereoisomerismo , Hongos/genética , Hongos/enzimología , Hongos/metabolismo , Filogenia , Catálisis , Biología Computacional/métodosRESUMEN
Alkaloids with a phenylhydrazone architecture are rarely found in nature. Four unusual phenylhydrazone alkaloids named talarohydrazones A-D (1-4) were isolated from the deep-sea cold seep derived fungus Talaromyces amestolkiae HDN21-0307 using the one strain-many compounds (OSMAC) approach and MS/MS-based molecular networking (MN) combined with network annotation propagation (NAP) and the unsupervised substructure annotation method MS2LDA. Their structures were elucidated by spectroscopic data analysis, single-crystal X-ray diffraction, and quantum chemical calculations. Talarohydrazone A (1) possessed an unusual skeleton combining 2,4-pyridinedione and phenylhydrazone. Talarohydrazone B (2) represents the first natural phenylhydrazone-bearing azadophilone. Bioactivity evaluation revealed that compound 1 exhibited cytotoxic activity against NCI-H446 cells with an IC50 value of 4.1 µM. In addition, compound 1 displayed weak antibacterial activity toward Staphylococcus aureus with an MIC value of 32 µg/mL.
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Alcaloides , Hidrazonas , Pruebas de Sensibilidad Microbiana , Staphylococcus aureus , Talaromyces , Talaromyces/química , Hidrazonas/farmacología , Hidrazonas/química , Alcaloides/farmacología , Alcaloides/química , Alcaloides/aislamiento & purificación , Estructura Molecular , Staphylococcus aureus/efectos de los fármacos , Humanos , Antibacterianos/farmacología , Antibacterianos/química , Antibacterianos/aislamiento & purificación , Ensayos de Selección de Medicamentos Antitumorales , Cristalografía por Rayos XRESUMEN
One new indole diterpenoid, ascandinine T (1), and three known analogues (2-4) were isolated from an Antarctic sponge-derived fungus Aspergillus candidus HDN15-152. The structures, including absolute configurations, were established based on NMR, HRESIMS, and electronic circular dichroism (ECD) calculations. All isolated compounds were tested for antiviral and anticancer activity. Compound 4 displayed antiviral activity against influenza A virus (IAV) of A/PR/8/34(H1N1) strain with an IC50 value of 39.2 µM, while compound 2 showed cytotoxicity against NCI-H446, NCI-H446/EP and L-02 cells with IC50 values ranging from 9.77 to 13.91 µM.
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Utilizing a gene evolution-oriented approach for gene cluster mining, a cryptic cytochalasin-like gene cluster (sla) in Antarctic-derived Simplicillium lamelliciola HDN13430 was identified. Compared with the canonical cytochalasin biosynthetic gene clusters (BGCs), the sla gene cluster lacks the key α,ß-hydrolase gene. Heterologous expression of the sla gene cluster led to the discovery of a new compound, slamysin (1), characterized by an N-acylated amino acid structure and demonstrating weak anti-Bacillus cereus activity. These findings underscore the potential of genetic evolution in uncovering novel compounds and indicating specific adaptive evolution within specialized habitats.
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Citocalasinas , Familia de Multigenes , Citocalasinas/química , Citocalasinas/farmacología , Estructura Molecular , Policétidos/química , Policétidos/farmacología , Regiones Antárticas , Bacillus cereus , Evolución MolecularRESUMEN
Cyclo-diphenylalanine (cFF) is a symmetrical aromatic diketopiperazine (DKP) found wide-spread in microbes, plants, and resulting food products. As different bioactivities continue being discovered and relevant food and pharmaceutical applications gradually emerge for cFF, there is a growing need for establishing convenient and efficient methods to access this type of compound. Here, we present a robust cFF production system which entailed stepwise engineering of the filamentous fungal strain Aspergillus nidulans A1145 as a heterologous expression host. We first established a preliminary cFF producing strain by introducing the heterologous nonribosomal peptide synthetase (NRPS) gene penP1 to A. nidulans A1145. Key metabolic pathways involving shikimate and aromatic amino acid biosynthetic support were then engineered through a combination of gene deletions of competitive pathway steps, over-expressing feedback-insensitive enzymes in phenylalanine biosynthesis, and introducing a phosphoketolase-based pathway, which diverted glycolytic flux toward the formation of erythrose 4-phosphate (E4P). Through the stepwise engineering of A. nidulans A1145 outlined above, involving both heterologous pathway addition and native pathway metabolic engineering, we were able to produce cFF with titers reaching 611 mg/L in shake flask culture and 2.5 g/L in bench-scale fed-batch bioreactor culture. Our study establishes a production platform for cFF biosynthesis and successfully demonstrates engineering of phenylalanine derived diketopiperazines in a filamentous fungal host.
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Aspergillus nidulans , Dipéptidos , Ingeniería Metabólica , Aspergillus nidulans/genética , Aspergillus nidulans/metabolismo , Reactores Biológicos , Fenilalanina/genética , Fenilalanina/metabolismoRESUMEN
Assisted by OSMAC strategy, one new p-terphenyl and two new αpyrone derivates, namely nocarterphenyl I (1) and nocardiopyrone D-E (2-3), were obtained and characterized from the marine sediment-derived actinomycete Nocardiopsis sp. HDN154086. The structures of these compounds were determined on the basis of MS, NMR spectroscopic data and single-crystal X-ray diffraction. Compound 1 with a rare 2,2'-bithiazole structure among natural products showed promising activity against five bacteria with MIC values ranging from 0.8 to 1.6 µM and 3 exhibited notable antibacterial activity against MRSA compared the positive control ciprofloxacin.
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Actinobacteria , Compuestos de Terfenilo , Actinobacteria/química , Nocardiopsis , Pironas/química , Estructura Molecular , Antibacterianos/química , Compuestos de Terfenilo/químicaRESUMEN
Heterologous biosynthesis has become an effective means to activate fungal silent biosynthetic gene clusters (BGCs) and efficiently utilize fungal genetic resources. Herein, thirteen labdane diterpene derivatives, including five undescribed ones named talarobicins A-E (3-7), were discovered via heterologous expression of a silent BGC (labd) in Aspergillus nidulans. Their structures with absolute configurations were elucidated using extensive MS and NMR spectroscopic methods, as well as electronic circular dichroism (ECD) calculations. These labdanes belong to four skeleton types, and talarobicin B (4) is the first 3,18-dinor-2,3:4,18-diseco-labdane diterpene with the cleavage of the C2-C3 bond in ring A and the decarboxylation at C-3 and C-18. Talarobicin B (4) represents the key intermediate in the biosynthesis of penioxalicin and compound 13. The combinatorial heterologous expression and feeding experiments revealed that the cytochrome P450 enzymes LabdC, LabdE, and LabdF were responsible for catalyzing various chemical reactions, such as oxidation, decarboxylation, and methylation. All of the compounds are noncytotoxic, and compounds 2 and 8 displayed inhibitory effects against methicillin-resistant coagulase-negative staphylococci (MRCNS) and Bacillus cereus.
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Aspergillus nidulans , Diterpenos , Talaromyces , Talaromyces/metabolismo , Diterpenos/química , Sistema Enzimático del Citocromo P-450 , Espectroscopía de Resonancia Magnética , Aspergillus nidulans/genética , Aspergillus nidulans/metabolismo , Estructura MolecularRESUMEN
Coumarins, isocoumarins and their derivatives are polyketides abundant in fungal metabolites. Although they were first discovered over 50 years ago, the biosynthetic process is still not entirely understood. Herein, we report the activation of a silent nonreducing polyketide synthase that encodes a C7-methylated isocoumarin, similanpyrone B (1), in a marine-derived fungus Simplicillium lamellicola HDN13-430 by heterologous expression. Feeding studies revealed the host enzymes can change 1 into its hydroxylated derivatives pestapyrone A (2). Compounds 1 and 2 showed moderate radical scavenging activities with ED50 values of 67.4 µM and 104.2 µM. Our discovery fills the gap in the enzymatic elucidation of naturally occurring C7-methylated isocoumarin derivatives.
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Hypocreales , Isocumarinas , Sintasas Poliquetidas , Cumarinas/farmacologíaRESUMEN
AIMS: Novel antimycin alkaloid antimycin A2c (AE) was isolated from the culture of a marine derived Streptomyces sp. THS-55. We elucidated its chemical structure by extensive spectra and clarified the specific mechanism in HPV infected-cervical cancer. MATERIALS AND METHODS: Colony formation assay, cell cycle analysis, hoechst 33342 staining assay, et.al were used to detect the inhibitory effect of AE on cervical cancer cells. Meanwhile, flow cytometry, western blotting, immunoprecipitation, RNA interference and molecular docking were used to analyze the mechanism of AE. KEY FINDINGS: AE exhibited potent cytotoxicity in vitro against HPV-transformed cervical cancer HeLa cell line. AE inhibited the proliferation, arrested cell cycle distribution, and triggered caspase dependent apoptosis in HeLa cells. Further studies revealed AE-induced apoptosis is mediated by the degradation of E6/E7 oncoproteins. Molecular mechanic investigation showed that AE degraded the levels of E6/E7 oncoproteins through reactive oxygen (ROS)-mediated ubiquitin-dependent proteasome system activation, and the increased ROS generation was due to the disruption of the mitochondrial function. SIGNIFICANCE: This present work revealed that this novel marine derived antimycin alkaloid could target the mitochondria and subsequently degrade HPV E6/E7 oncoproteins, and have potential application in the design and development of lead compound for cervical cancer cells, as well as the development for tool compounds to dissect E6/E7 functions.
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Antineoplásicos , Proteínas Oncogénicas Virales , Infecciones por Papillomavirus , Streptomyces , Neoplasias del Cuello Uterino , Femenino , Humanos , Células HeLa , Neoplasias del Cuello Uterino/genética , Streptomyces/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Simulación del Acoplamiento Molecular , Proteínas Oncogénicas Virales/genética , Proteínas E7 de Papillomavirus , Antineoplásicos/farmacología , Antineoplásicos/metabolismo , Mitocondrias/metabolismoRESUMEN
A new alkaloid named aspergilalkaloid A (1) with pyridoindole hydroxymethyl piperazine dione structure along with six known compounds 2-7 were isolated from deep-sea derived fungus Aspergillus sp. HDN20-1401. The structure including absolute configuration was elucidated by extensive NMR analyses, HRESIMS, ECD calculation, and theoretical NMR calculation with DP4+ analysis. All isolated compounds were tested for antimicrobial and anticancer activity. Aspergilalkaloid A (1) showed inhibitive activity against Bacillus cereus with MIC value of 12.5 µM and weak activity against MRCNS.
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Six angucyclines including three unreported compounds (1-3) were isolated from Streptomyces sp. XS-16 by overexpressing the native global regulator of SCrp (cyclic AMP receptor). The structures were characterized based on nuclear magnetic resonance (NMR) and spectrometry analysis and assisted by electronic circular dichroism (ECD) calculations. All compounds were tested for their antitumor and antimicrobial activities, and compound 1 showed different inhibitory activities against various tumor cell lines with IC50 values ranging from 0.32 to 5.33 µM.
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Antineoplásicos , Streptomyces , Antineoplásicos/química , Streptomyces/metabolismo , Línea Celular Tumoral , Espectroscopía de Resonancia Magnética , Estructura MolecularRESUMEN
Polymer semiconductors with mobilities exceeding 10 cm2 V- 1 s- 1 , especially ambipolar and n-type polymer semiconductors, are still rare, although they are of great importance for fabricating polymer field-effect transistors (PFETs) toward commercial high-grade electronics. Herein, two novel donor-acceptor copolymers, PNFFN-DTE and PNFFN-FDTE, are designed and synthesized based on the electron-deficient bisisoindigo (NFFN) and electron-rich dithienylethylenes (DTE or FDTE). The copolymer PNFFN-DTE, containing NFFN and DTE, possesses a partially locked polymeric conjugated backbone, whereas PNFFN-FDTE, containing NFFN and FDTE, has a fully locked one. Fluorine atoms in FDTE not only induce the formation of additional CHâââF hydrogen bonds, but also lower frontier molecular orbitals for PNFFN-FDTE. Both PNFFN-DTE and PNFFN-FDTE form more ordered molecular packing in thin films prepared from a polymer solution in bicomponent solvent containing 1,2-dichlorobenzene (DCB) and 1-chloronaphthalene (with volume ratio of 99.2/0.8) than pure DCB. The two copolymers-based flexible PFETs exhibit ambipolar charge-transport properties. Notably, the bicomponent solvent-processed PNFFN-FDTE-based PFETs afford a high electron mobility of 16.67 cm2 V-1 s-1 , which is the highest electron-transport mobility for PFETs reported so far. The high electron mobility of PNFFN-FDTE is attributed to its fully locked conjugated backbone, dense molecular packing, and much matched LUMO energy level.
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Sixteen new biisoflavones, bisoflavolins A-N (1-16), were discovered from cultures of the Takla Makan desert-derived strain Streptomyces sp. HDN154127. The chemical structures, including axial chirality, were elucidated by NMR, MS, and ECD analyses. Antibacterial activity of dimerized compounds was tested against seven different bacteria. The dimerized compounds showed better activity (MIC from 0.8 to 50.0 µM) than the corresponding monomers (daidzein and genistein, MIC > 50.0 µM). The rare dimeric and chlorinated structures in 1-16 were proved to be biotransformation products obtained from soy isoflavones and sodium chloride, which constituted the culture medium. This is the first report of an actinomycete that promotes both dimerization and chlorination utilizing natural isoflavones as skeletons sources.