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1.
Nat Prod Res ; : 1-10, 2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38695089

RESUMO

Rubrolides are natural butyrolactones isolated from the tunicate Ritterella rubra, shows antibacterial, antiviral and plant photosynthesis inhibitory activities. In this study, a facile total synthetic method for preparing the rubrolides from benzaldehyde by a Darzens reaction, aldol reaction and vinylogous aldol condensation in five steps is presented. Three natural rubrolides (E, C and F) were synthesised in the total yields of 25-40%. The bioassay results indicate that rubrolides E, C and F exhibit some herbicidal inhibitory effect against rapeseed, in particular, rubrolide F shows the best herbicidal activities against rapeseed root with the growth inhibitory rate of 72.8%. At greenhouse treatment concentrations of 100 and 500 mg/L, rubrolide F show a positive dose-toxicity correlation towards abutilon plants. Collectively, facile total Synthesis strategy provided the base for further bioactivities study of rubrolides family. Rubrolide F may be act as inhibitor of photosynthesis, and this could be lead structure of new herbicide.

2.
Langmuir ; 40(23): 12089-12096, 2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38804669

RESUMO

Developing inexpensive, efficient, and stable catalysts is crucial for reducing the cost of electrolytic hydrogen production. Recently, polyoxometalates (POMs) have gained attention and widespread use due to their excellent electrocatalytic properties. This study designed and synthesized three composite materials, NF/PMonW12-n, by using phosphomolybdic-tungstic heteropolyacids as precursors to grow in situ on nickel foam via the hydrothermal process and subsequent calcination. Then, their catalytic performances are systematically investigated. This work demonstrates that the NF/PMonW12-n catalysts generate more low valent oxides under the synergistic effect of Mo and W, further enhancing activity for hydrogen evolution reaction (HER). Among these electrocatalysts, NF/PMo6W6 exhibits the perfect HER performance, η10 is only 74 mV. It also shows great stability during long-term electrolysis. The current study introduces a fresh approach for producing electrocatalysts that are both cost-effective and highly efficient.

3.
Small ; : e2401050, 2024 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-38511580

RESUMO

Polymeric semiconducting materials struggle to achieve fast charge mobility due to low structural order. In this work, five 1H-indene-1,3(2H)dione-benzene structured halogenated solid additives namely INB-5F, INB-3F, INB-1F, INB-1Cl, and INB-1Br with gradually varied electrostatic potential are designed and utilized to regulate the structural order of polymer donor PM6. Molecular dynamics simulations demonstrate that although the dione unit of these additives tends to adsorb on the backbone of PM6, the reduced electrostatic potential of the halogen-substituted benzene can shift the benzene interacting site from alkyl side chains to the conjugated backbone of PM6, not only leading to enhanced π-π stacking in out-of-plane but also arising new π-π stacking in in-plane together with the appearance of multiple backbone stacking in out-of-plane, consequent to the co-existence of face-on and edge-on molecular orientations. This molecular packing transformation further translates to enhanced charge transport and suppressed carrier recombination in their photovoltaics, with a maximum power conversion efficiency of 19.4% received in PM6/L8-BO layer-by-layer deposited organic solar cells.

4.
Int J Rheum Dis ; 27(1): e15031, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38287544

RESUMO

OBJECTIVES: To evaluate the efficacy and safety of adalimumab (ADA) combined with Tripterygium wilfordii Hook F (TwHF) in the treatment of methotrexate (MTX)-inadequate response patients with rheumatoid arthritis (RA). METHODS: In this multicenter, open-label, randomized controlled clinical trial, 64 RA patients with inadequate response to MTX were 1:1 randomly assigned into treatment or control groups. The treatment group was treated with ADA in combination with TwHF, and the control group was treated with ADA in combination with MTX for 24 weeks. The primary endpoint was the percentage of patients having low disease activity (2.6 ≤ DAS28-ESR < 3.2) and remission rates (DAS28-ESR < 2.6) at week 24. RESULTS: In total, 53 of the 64 patients (82.8%) completed this 24-week clinical trial. By intent-to-treat (ITT) analysis, a comparable outcome was observed between the two groups. The percentage of patients achieving low disease activity in the treatment group and control group were 43.8% and 46.9% (95% CI, 21.28 to 27.48, p = .802). Percentage of patients achieving low disease activity rates were respectively 28.1% and 31.3% in the treatment group and control group (95% CI, 19.18 to 25.58, p = .784). In per-protocol (PP) analysis, the results were consistent with the ITT model. The incidence of adverse events was comparable between the two groups. CONCLUSIONS: There were no significant differences in efficacy and safety between ADA combined with TwHF versus ADA combined with MTX in the treatment of RA. TwHF might be an alternative treatment for RA patients who are intolerant to MTX.


Assuntos
Antirreumáticos , Artrite Reumatoide , Humanos , Adalimumab/efeitos adversos , Antirreumáticos/efeitos adversos , Tripterygium , Artrite Reumatoide/diagnóstico , Artrite Reumatoide/tratamento farmacológico , Artrite Reumatoide/induzido quimicamente , Metotrexato/efeitos adversos , Quimioterapia Combinada , Resultado do Tratamento
5.
Langmuir ; 40(1): 744-750, 2024 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-38103033

RESUMO

To explore, highly active electrocatalysts are essential for water splitting materials. Polyoxometalates (POMs) have drawn interesting attention in recent years due to their abundant structure and unique electrocatalytic properties. In this study, by using a POM-based precursor Co2Mo10, novel bimetallic sulfide (CoS2-MoS2) nanocomposites are rationally designed and synthesized under hydrothermal conditions. The incorporation of Co2+ to the host electrocatalyst could effectively increase the exposure of active sites of MoS2. Compared to pure MoS2, the CoS2-MoS2 nanocomposite exhibited a perfect hydrogen evolution reaction (HER) ability, for it merely requires overpotentials of 120 and 153 mV for 10 mA cm-2 working current density toward the HER in 1 M KOH and 0.5 M H2SO4 electrolyte systems, respectively. Additionally, the nanocomposite exhibited outstanding chemical stability and long-term durability. This study presents a novel strategy that utilizes POMs to enrich the exposed edge sites of MoS2, resulting in the preparation of efficient electrocatalysts.

6.
Nat Commun ; 14(1): 6297, 2023 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-37813902

RESUMO

Conjugated polymers are generally featured with low structural order due to their aromatic and irregular structural units, which limits their light absorption and charge mobility in organic solar cells. In this work, we report a conjugated molecule INMB-F that can act as a molecular bridge via electrostatic force to enhance the intermolecular stacking of BDT-based polymer donors toward efficient and stable organic solar cells. Molecular dynamics simulations and synchrotron X-ray measurements reveal that the electronegative INMB-F adsorb on the electropositive main chain of polymer donors to increase the donor-donor interactions, leading to enhanced structural order with shortened π-π stacking distance and consequently enhanced charge transport ability. Casting the non-fullerene acceptor layer on top of the INMB-F modified donor layer to fabricate solar cells via layer-by-layer deposition evidences significant power conversion efficiency boosts in a range of photovoltaic systems. A power conversion efficiency of 19.4% (certified 18.96%) is realized in PM6/L8-BO binary devices, which is one of the highest reported efficiencies of this material system. The enhanced structural order of polymer donors by INMB-F also leads to a six-fold enhancement of the operational stability of PM6/L8-BO organic solar cells.

7.
BMC Genomics ; 24(1): 275, 2023 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-37217849

RESUMO

BACKGROUND: Armillaria species are plant pathogens, but a few Armillaria species can establish a symbiotic relationship with Gastrodia elata, a rootless and leafless orchid, that is used as a Chinese herbal medicine. Armillaria is a nutrient source for the growth of G. elata. However, there are few reports on the molecular mechanism of symbiosis between Armillaria species and G. elata. The genome sequencing and analysis of Armillaria symbiotic with G. elata would provide genomic information for further studying the molecular mechanism of symbiosis. RESULTS: The de novo genome assembly was performed with the PacBio Sequel platform and Illumina NovaSeq PE150 for the A. gallica Jzi34 strain, which was symbiotic with G. elata. Its genome assembly contained ~ 79.9 Mbp and consisted of 60 contigs with an N50 of 2,535,910 bp. There were only 4.1% repetitive sequences in the genome assembly. Functional annotation analysis revealed a total of 16,280 protein coding genes. Compared with the other five genomes of Armillaria, the carbohydrate enzyme gene family of the genome was significantly contracted, while it had the largest set of glycosyl transferase (GT) genes. It also had an expansion of auxiliary activity enzymes AA3-2 gene subfamily and cytochrome P450 genes. The synteny analysis result of P450 genes reveals that the evolutionary relationship of P450 proteins between A. gallica Jzi34 and other four Armillaria was complex. CONCLUSIONS: These characteristics may be beneficial for establishing a symbiotic relationship with G. elata. These results explore the characteristics of A. gallica Jzi34 from a genomic perspective and provide an important genomic resource for further detailed study of Armillaria. This will help to further study the symbiotic mechanism between A. gallica and G. elata.


Assuntos
Armillaria , Gastrodia , Armillaria/genética , Simbiose/genética , Gastrodia/genética , Sequenciamento Completo do Genoma
8.
PLoS One ; 17(11): e0277701, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36409681

RESUMO

A symbiotic relationship is observed between Armillaria and the Chinese herbal medicine Gastrodia elata (G. elata). Armillaria is a nutrient source for the growth of G. elata, and its nutrient metabolism efficiency affects the growth and development of G. elata. Auxin has been reported to stimulate Armillaria species, but the molecular mechanism remains unknown. We found that naphthalene acetic acid (NAA) can also promote the growth of A. gallica. Moreover, we identified a total of 2071 differentially expressed genes (DEGs) by analyzing the transcriptome sequencing data of A. gallica at 5 and 10 hour of NAA treatment. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses showed that these unigenes were significantly enriched in the metabolism pathways of arginine, proline, propanoate, phenylalanine and tryptophan. The expression levels of the general amino acid permease (Gap), ammonium transporter (AMT), glutamate dehydrogenase (GDH), glutamine synthetase (GS), Zn(II) 2Cys6 and C2H2 transcription factor genes were upregulated. Our transcriptome analysis showed that the amino acid and nitrogen metabolism pathways in Armillaria were rapidly induced within hours after NAA treatment. These results provide valuable insights into the molecular mechanisms by which NAA promotes the growth of Armillaria species.


Assuntos
Armillaria , Gastrodia , Armillaria/genética , Ácidos Naftalenoacéticos , Perfilação da Expressão Gênica , Ontologia Genética
9.
Molecules ; 27(15)2022 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-35956949

RESUMO

The Kleier model and Carrier-mediated theory are effective for molecularly designing pesticides with phloem mobility. However, the single Kleier model or Carrier-mediated theory cannot achieve a reliable explanation of the phloem mobility of all exogenous substances. A detailed investigation of the two models and the scope of their applications can provide a more accurate and highly efficient basis for the guidance of the design and development of phloem-mobile pesticides. In the present paper, a strategy using active ingredient-amino acid conjugates as mode compounds is developed based on Carrier-mediated theory. An N-alkylated amino acid is used to improve the pesticide's physicochemical properties following the Kleier model, thus allowing the conjugates to fall on the predicted and more accessible transportation region of phloem. Moreover, the influence of this movement on phloem is inspected by the Kleier model and Carrier-mediated theory. To verify this strategy, a series of N-alkylated phenazine-1-carboxylic acid-glycine compounds (PCA-Gly) were designed and synthesized. The results related to the castor bean seeds (R. communis L.) indicated that all the target compounds (4a−4f) had phloem mobility. The capacity for phloem mobility shows that N-alkylated glycine containing small substituents can significantly improve PCA phloem mobility, such as 4c(i-C3H7-N) > 4a(CH3-N) ≈ 4b(C2H5-N) > 4d (t-C4H9-N) > PCA-Gly > 4e(C6H5-N) > 4f(CH2COOH-N), with an oil−water partition coefficient between 1.2~2.5. In particular, compounds 4a(CH3-N), 4b(C2H5-N), and 4c(i-C3H7-N) present better phloem mobility, with the average concentrations in phloem sap of 14.62 µΜ, 13.98 µΜ, and 17.63 µΜ in the first 5 h, which are 8 to 10 times higher than PCA-Gly (1.71 µΜ). The results reveal that the Kleier model and Carrier-mediated theory play a guiding role in the design of phloem-mobile pesticides. However, the single Kleier model or Carrier-mediated theory are not entirely accurate. Still, there is a synergism between Carrier-mediated theory and the Kleier model for promoting the phloem transport of exogenous compounds. Therefore, we suggest the introduction of endogenous plant compounds as a promoiety to improve the phloem mobility of pesticides through Carrier-mediated theory. It is necessary to consider the improvement of physicochemical properties according to the Kleier model, which can contribute to a scientific theory for developing phloem-mobile pesticides.


Assuntos
Fabaceae , Praguicidas , Aminoácidos/química , Fabaceae/metabolismo , Glicina/farmacologia , Praguicidas/análise , Fenazinas , Floema/química , Ricinus/metabolismo
10.
PLoS One ; 17(5): e0266049, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35609017

RESUMO

A rapid shrinkage of Daihai Lake was found in recent decades. The present study analyzed the characteristics of Daihai Lake shrinkage and quantified the contribution of climate and human activities. The results of Mann-Kendall- Sneyers test and moving t-test showed that there was an obvious mutation point of lake level in 2006 and the descending speed of Daihai Lake level post-2006 (-0.46m/a) was 3.22 times that of pre-2006 (-0.14m/a). The centroid of Daihai Lake moved 1365.18 m from southwest to northeast during 1989 ~ 2018 with an average speed of 47.08 m/a. The results of Mann-Kendall trend test revealed that the annual evaporation showed a significant downward trend with a rate of approximately -5.33 mm/a, while no significant trend was found in precipitation. Daihai lake water level showed a very weak relationship with evaporation (r = 0.078, p < 0.01) and precipitation (p>0.05) respectively. Daihai Lake was influenced by human activities mainly from land use/ land cover, building reservoirs, pumping groundwater and directly consuming Daihai Lake water by Daihai power plant (DHPP). It was thought-provoking that DHPP began to consume Daihai lake water in 2006, which was consistent with abrupt change of Daihai lake level. The proportion of human impact was fluctuating upward. Human factors were the main factor of lake water reduction in last 10 years and the 5-year average contribution of human activities to Daihai Lake shrinkage was more than 61.99%. More attention and economic support should be given to prevent the continuous shrinkage of Daihai Lake.


Assuntos
Água Subterrânea , Lagos , China , Mudança Climática , Monitoramento Ambiental , Atividades Humanas , Humanos , Água
11.
Pestic Biochem Physiol ; 183: 105086, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35430076

RESUMO

To improve the selectivity of the fenoxaprop herbicide to rice and barnyard grass, a series of fenoxaprop-P-ethyl-amino acid ester conjugates were designed and synthesized, and tested for biological activity as well as their phloem mobility. The bioassay results indicated that the target compounds possessed better activity against barnyard grass (Echinochloa crusgalli) than rape (Brassica campestris L.) at the concentration of 0.5 mmol/L. Compounds 3h and 3i, showed more than 70% control efficiency against barnyard grass, while less than 30% for rape. The compounds showed less impact on rice after spray treatment than in the germination test. Compounds 3i, 3j, and 3k showed excellently herbicidal activities against barnyard grass and low phytotoxicity to rice. Compound 3k showed 6.1% phytotoxicity to rice at a spray concentration of 0.25 mmol/L, better than fenoxaprop-P-ethyl (61.6%) at the same concentration. The selectivity results of the target compounds revealed that most of compounds obviously reduced phytotoxicity to rice while retaining herbicidal activity of barnyard grass. The herbicidal activity of compound 3d compared to FPE was increased by 50%, while its safety on rice was also increased by 50%. The concentration of the compounds in barnyard grass roots was higher than in rice roots, showing greater phloem mobility. In particular, the concentration of compound 3d on barnyard grass exhibited 142.72 mg/kg which was 3 times as much as Fenoxaprop, while its concentration on rice exhibited 3.65 mg/kg, the results revealed that the difference of phloem mobility might be the important reason for causing the selectivity.


Assuntos
Echinochloa , Herbicidas , Oryza , Aminoácidos/metabolismo , Echinochloa/metabolismo , Ésteres/metabolismo , Herbicidas/química , Herbicidas/toxicidade , Oryza/metabolismo , Floema/fisiologia
12.
Small ; 17(35): e2102558, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34293248

RESUMO

The additive strategy is widely used in optimizing the morphology of organic solar cells (OSCs). The majority of additives are liquid with high boiling points, which will be trapped within device and consequently deteriorate performance during operation. In this work, solid but volatile additives 2-(4-fluorobenzylidene)-1H-indene-1,3(2H)-dione (INB-F) and 2-(4-chlorobenzylidene)-1H-indene-1,3(2H)-dione (INB-Cl) are designed to replace the common 1,8-diiodooctane (DIO) in nonfullerene OSCs. These additives present during solution casting but evaporate after moderate heating. Molecular dynamics simulations show that they can reduce the adsorption energy to improve π-π stacking among nonfullerene acceptor (NFA) molecules, an effect that enhances light absorption and electron mobility. Both INB-F and INB-Cl enhance efficiency, with INB-F achieving a maximum efficiency of 16.7% from 15.1% of the reference PBDB-T-2F (PM6):BTP-BO-4F (Y6-BO) cell, and outperforming DIO. Remarkably, they can simultaneously enhance the operational stability, with the INB-F-treated OSC maintaining over 60% of the initial efficiency after 1000 h operation, demonstrating a T80 lifetime of 523 h, which is a significant improvement over T80 values of 66.2 h for the reference and 6.6 h for DIO-treated OSC. The simultaneously enhanced efficiency and operational lifetime are also effective in PM6:BTP-BO-4Cl (Y7-BO) OSCs, demonstrating a universal strategy to improve the performance of OSCs.

13.
Nat Prod Res ; 35(24): 5773-5777, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33078656

RESUMO

The introduction of fluorine atom can increase the biological activities of the target compounds remarkably. To find more safe and efficient insecticides, natural product galegine as lead compound, a series of novel fluorinated galegine analogues were designed and synthesized. The bioassay results indicate that all the target compounds have moderate to high insecticidal activities against Hyalopterus pruni Geoffroy and Aphis gossypii Glover, in particular, compounds IIa-05, IId-02 and IIe-03 show the best insecticidal activities against Hyalopterus pruni with the mortality of 100%, 100% and 96.6%, respectively. And compounds IIa-02, IId-02, IId-04, IIc-01, IIc-02 and IId-01 show 0.6-7 times insecticidal activities against Aphis gossypii as Imidacloprid with their LC50 values are 0.28 mg/L, 0.38 mg/L, 0.33 mg/L, 0.09 mg/L, 0.03 mg/L and 0.12 mg/L, respectively The analysis of structure-activity relationship indicates that the compounds with difluoro-substituted benzene ring have more potent insecticidal activities than the single fluoro-substituted compounds.


Assuntos
Afídeos , Inseticidas , Animais , Guanidinas , Inseticidas/farmacologia , Relação Estrutura-Atividade
14.
Cell Tissue Res ; 382(3): 563-574, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32725426

RESUMO

This study aimed to explore the effect of Sgk1 on Th9 differentiation and the underlying mechanism in asthma. The asthmatic mouse model induced by ovalbumin (OVA) and CD4+T cells which were cultured with TGF-ß, IL-2, IL-4, and anti-IFN-γ were applied in vivo and in vitro, respectively. Flow cytometry, quantitative real-time PCR (qRT-PCR), and ELISA were performed to detect T-helper 9 (Th9) cells, IL-9 expression, and IL-9 release. Western blot was performed to examine phosphorylated(p)-IKKα, p-IκBα, p-p65, and IRF4 levels. Hematoxylin/eosin (H&E) staining was adopted to assess pathological changes of lung tissues. Inhibition of Sgk1 dramatically reversed elevated Th9 cells and IL-9 expression in the lung tissues of asthmatic mice. In vitro, Sgk1 promoted Th9 differentiation and elevated p-IKKα, p-IκBα, p-p65, and IRF4 levels, but inhibition of IKKα/IκBα/p65 pathway and IRF4 both reversed enhanced Th9 differentiation by Sgk1. Sgk1→IKKα/IκBα/NF-κBp65→IRF4→Th9 axis may be implicated in asthma development.


Assuntos
Asma/genética , Proteínas Imediatamente Precoces/metabolismo , Inflamação/metabolismo , NF-kappa B/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Animais , Diferenciação Celular/fisiologia , Modelos Animais de Doenças , Feminino , Proteínas Imediatamente Precoces/genética , Inflamação/genética , Inflamação/patologia , Camundongos , Camundongos Endogâmicos BALB C , Proteínas Serina-Treonina Quinases/genética , Transdução de Sinais
15.
ACS Appl Mater Interfaces ; 11(41): 37833-37841, 2019 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-31538760

RESUMO

Perovskite solar cells (PSCs) have demonstrated encouraging progress in recent years. Additive engineering, where diverse additives are incorporated into the perovskite layer, has been widely adopted to tune the perovskite grains, reduce defect density and charge recombination. Here, we observe a universal phenomenon that organic chloride additives enhance the open circuit voltage (VOC) and power conversion efficiencies (PCEs) of direct PSCs but decrease the VOC, short-circuit current (JSC), and PCE of inverted PSCs, regardless of the choice of charge transport materials. The polyTPD-based direct device incorporating trimethylammonium chloride (TACl) additive delivery improved PCE from 17.8 to 20.0%, arising from the enhanced VOC from 1.03 to 1.12 V. With the same content of TACl, the best PCE of the polyTPD-based inverted device decreased from 20.2 to 18.5% because of the reduced VOC (1.05-1.01 V) and JSC (23.2-22.5 mA/cm2). Our investigation confirms that organic chloride will p-dope perovskites and elevate the work functions, which lead to favorable/unfavorable charge transfer between perovskite films and its upper transport layers in direct and inverted devices. This work provides an insight into the rational design of the device structure when applying additives which can dope the perovskite to affect charge transfer at the perovskite/charge transport layer interface.

16.
ACS Appl Mater Interfaces ; 11(29): 26194-26203, 2019 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-31283167

RESUMO

Fluorination of conjugated molecules has been established as an effective structural modification strategy to influence properties and has attracted extensive attention in organic solar cells (OSCs). Here, we have investigated optoelectronic and photovoltaic property changes of OSCs made of polymer donors with the non-fullerene acceptors (NFAs) ITIC and IEICO and their fluorinated counterparts IT-4F and IEICO-4F. Device studies show that fluorinated NFAs lead to reduced Voc but increased Jsc and fill-factor (FF), and therefore, the ultimate influence to efficiency depends on the compensation of Voc loss and gains of Jsc and FF. Fluorination lowers energy levels of NFAs, reduces their electronic band gaps, and red-shifts the absorption spectra. The impact of fluorination on the molecular order depends on the specific NFA, and the conversion of ITIC to IT-4F reduces the structural order, which can be reversed after blending with the donor PBDB-T. Contrastingly, IEICO-4F presents stronger π-π stacking after fluorination from IEICO, and this is further strengthened after blending with the donor PTB7-Th. The photovoltaic blends universally present a donor-rich surface region which can promote charge transport and collection toward the anode in inverted OSCs. The fluorination of NFAs, however, reduces the fraction of donors in this donor-rich region, consequently encouraging the intermixing of donor/acceptor for efficient charge generation.

17.
Nat Prod Res ; 33(12): 1727-1733, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29457519

RESUMO

A new homoisoflavonoid, (3R)-5,7-dihydroxy-6-methyl-3-(2'-hydroxy-4'-methoxybenzyl)-chroman-4-one (1), namely polygonatone H, in addition to fourteen known homoisoflavones (2-15) were isolated from the rhizome of Polygonatum Cyrtonema Hua. The structures were identified with the aid of 1D/2D NMR spectroscopic technologies. Compounds 2, 6, 8, 10, 11, 13, and 15 were isolated from P. Cyrtonema for the first time. Compound 1 showed cytotoxicities to human cancer cell lines with IC50 values to comparable those of cisplatin.


Assuntos
Antineoplásicos/isolamento & purificação , Isoflavonas/isolamento & purificação , Isoflavonas/toxicidade , Polygonatum/química , Rizoma/química , Antineoplásicos/química , Antineoplásicos/farmacologia , Linhagem Celular , Citotoxinas/química , Citotoxinas/isolamento & purificação , Citotoxinas/farmacologia , Humanos , Concentração Inibidora 50 , Isoflavonas/química , Espectroscopia de Ressonância Magnética , Estrutura Molecular
18.
ACS Appl Mater Interfaces ; 10(39): 33144-33152, 2018 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-30192502

RESUMO

Stability remains as a challenge of perovskite solar cells although encouraging progress has been made toward their maximum achievable power conversion efficiency in recent years. Light-soaking issue, where the device performance improves upon continuous light illumination and reduces upon storage in dark, is widely observed and marked as the early-stage instability during device operation. In this work, we have employed conjugated polymer PCDTBT as the dopant-free hole-transport layer to fabricate devices without hysteresis but with reversible light-soaking instability. The introduction of n-type molecules, either organic molecule PDI2 or fullerene derivative PC61BM, as the interfacial layer between TiO2 and perovskite layers can effectively reduce or eliminate this instability owing to the efficient charge transport and defect passivation at the electron-transport layer interface, accompanied with an efficiency of 15.7 and 17.7%, respectively. We conclude that the light-soaking instability of these perovskite solar cells is mainly originated from the charge accumulation at the TiO2/perovskite interface and can be eliminated once the interfacial charge can be suppressed by interfacial modifications to improve charge transport at the interface.

19.
ACS Appl Mater Interfaces ; 9(38): 32678-32687, 2017 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-28870067

RESUMO

Metal oxide charge transport layers have been widely employed to prepare inverted polymer solar cells with high efficiency and long lifetime. However, the intrinsic defects in the metal oxide layers, especially those prepared from low-temperature routes, overshadow the high efficiency that can be achieved and also introduce "light-soaking" issues to these devices. In this work, we have employed polyethyleneimine (PEI) and poly(9,9-bis(6'-(N,N-diethylamino)propyl)-fluorene-alt-9,9-bis-(3-ethyl(oxetane-3-ethyloxy)-hexyl)-fluorene] (PFN-OX) to modify our low-temperature-processed TiO2 electron transport layer (ETL) and demonstrated that the light-soaking issue can be effectively eliminated by PEI modifications because of the formation of abundant dipole moments, whereas PFN-OX was ineffective as a result of deficient dipole moments at the interface. Excitingly, PEI modifications enable versatile device architectures to obtain light-soaking-free, inverted PTB7-Th:PC71BM solar cells with efficiencies of over 10%, by adding PEI either in the bulk or as an adjacent layer below or above the TiO2 ETL.

20.
J Asian Nat Prod Res ; 19(2): 164-171, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27618876

RESUMO

Two new phenolic acid compounds, asparoffin C (1) and asparoffin D (2), together with four known compounds, asparenyol (3), gobicusin B (4), 1-methoxy-2-hydroxy-4-[5-(4-hydroxyphenoxy)-3-penten-1-ynyl] phenol (5), and asparinin A (6), have been isolated from the stems of Asparagus officinalis. The structures were established by extensive spectroscopic methods (MS and 1D and 2D NMR). Compound 6 has obvious antitumor activities both in vitro and in vivo.


Assuntos
Alcinos/isolamento & purificação , Alcinos/farmacologia , Asparagus/química , Fenóis/isolamento & purificação , Fenóis/farmacologia , Alcinos/química , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Fenóis/química
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