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Various semiconductor devices have been developed based on 2D heterojunction materials owing to their distinctive optoelectronic properties. However, to achieve efficient charge transfer at their interface remains a major challenge. Herein, an alloy heterojunction concept is proposed. The sulfur vacancies in ZnIn2S4 are filled with selenium atoms of PdSe2. This chemically bonded heterojunction can significantly enhance the separation of photocarriers, providing notable advantages in the field of photoelectric conversion. As a demonstration, a two-terminal photodetector based on the PdSe2/ZnIn2S4 heterojunction materials is fabricated. The photodetector exhibits stable operation in ambient conditions, showcasing superior performance in terms of large photocurrent, high responsivity (48.8 mA W-1) and detectivity (1.98 × 1011 Jones). To further validate the excellent optoelectronic performance of the heterojunction, a tri-terminal phototransistor is also fabricated. Benefiting from gate voltage modulation, the photocurrent is amplified to milliampere level, and the responsivity is increased to 229.14 mA W-1. These findings collectively demonstrate the significant potential of the chemically bonded PdSe2/ZnIn2S4 alloy heterojunction for future optoelectronic applications.
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Photovoltaic device is highly dependent on the weather, which is completely ineffective on rainy days. Therefore, it is very significant to design an all-weather power generation system that can utilize a variety of natural energy. This work develops a water droplet friction power generation (WDFG)/solar-thermal power generation (STG) hybrid system. The WDFG consists of two metal electrodes and a candle soot/polymer composite film, which also can be regarded as a capacitor. Thus, the capacitor coupled power generation (C-WDFG) device can achieve a sustainable and stable direct-current (DC) output under continuous dripping without external conversion circuits. A single device can produce an open-circuit voltage of ca.0.52 V and a short-circuit current of ca.0.06 mA, which can be further scaled up through series or parallel connection to drive commercial electronics. Moreover, we demonstrate that the C-WDFG is highly compatible with the thermoelectric device. The excellent photothermal performance of soot/polymer composite film can efficiently convert solar into heat, which is then converted to electricity by the thermoelectric device. Therefore, this C-WDFG/STG hybrid system can work in both rainy and sunny days.
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Pseudorabies virus (PRV) is considered to be a promising oncolytic virus that has potential as a cancer gene therapy drug. In this study, PRV-DCD-1-70 was used as a vector to carry exogenous genes IL-18, IFN-γ and PH20 to construct novel recombinant PRV, rPRV-PH20 and rPRV-IL-18-γ-PH20, and their tumorolytic effects were evaluated in vitro and in vivo. Our study showed that recombinant PRV lysed all four tumor cell lines, Pan02, EMT-6, CT26 and H446, and rPRV-IL-18-γ-PH20 showed the best tumor lysis effect. Further studies in mice bearing Pan02 tumors showed that recombinant PRV, especially rPRV-IL-18-γ-PH20, were able to inhibit tumor growth. Moreover, an immunohistochemical analysis indicated that the recombinant PRV effectively increased the infiltration of CD4+T and CD8+T cells and enhanced the anti-tumor immune response of the organism in vivo. Overall, PRV carrying PH20 and IL-18-γ exogenous genes demonstrated anti-tumor effects, providing a foundation for the further development and application of PRV as a novel tumor oncolytic virus vector.
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In this work, we developed a library of sulfated glycomimetic polypeptides with a high sulfated degree (up to 99%) via a click reaction and sulfation modification, enabling control over the helicity, molecular weight, rigidity, and side-chain structure. Their potentials as the inhibitors of SARS-CoV-2 and common enterovirus were investigated, and the structure-activity relationship was explored in detail. The in vitro results revealed the crucial role of α-helical conformation and sulfated sugar since all the sulfated glycopolypeptides exhibited outperformed activity in suppressing SARS-CoV-2 infection with the inhibition efficiency up to 85%. Other structural properties, including the rigid chain structure and a moderate molecular weight, also contributed to blocking the viral entry into host cells. Among the sulfated glycopolypeptides, L60-SG-POB showed the highest inhibition efficiency with an IC50 of 0.71 µg/mL. Furthermore, these optimized sulfated glycopolypeptides were also capable of preventing enterovirus infection with the inhibition efficiency of up to 86%. This work opens new avenues for the development of synthetic polypeptides bearing sulfated sugars against SARS-CoV-2 and other viruses.
Assuntos
Antivirais , COVID-19 , Humanos , Antivirais/farmacologia , SARS-CoV-2 , Sulfatos/química , Peptídeos/farmacologia , Peptídeos/químicaRESUMO
Photodynamic therapy and sonodynamic therapy are two highly promising modalities for cancer treatment. The latter holds an additional advantage in deep-tumor therapy owing to the deep penetration of the ultrasonic radiation. The therapeutic efficacy depends highly on the photo/ultrasound-responsive properties of the sensitizers as well as their tumor-localization property and pharmacokinetics. A novel nanosensitizer system based on a polymeric phthalocyanine (pPC-TK) is reported herein in which the phthalocyanine units are connected with cleavable thioketal linkers. Such polymer could self-assemble in water forming nanoparticles with a hydrodynamic diameter of 48 nm. The degradable and flexible thioketal linkers could effectively inhibit the π-π stacking of the phthalocyanine units, rendering the resulting nanoparticles an efficient generator of reactive oxygen species upon light or ultrasonic irradiation. The nanosensitizer could be internalized into cancer cells readily, inducing cell death by efficient photodynamic and sonodynamic effects. The potency is significantly higher than that of the monomeric phthalocyanine (PC-4COOH). The nanosensitizer could also effectively inhibit the growth of tumor in liver tumor-bearing mice by these two therapies without causing noticeable side effects. More importantly, it could also retard the growth of a deep-located orthotopic liver tumor in vivo by sonodynamic therapy.
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Neoplasias Hepáticas , Nanopartículas , Fotoquimioterapia , Terapia por Ultrassom , Animais , Camundongos , Fotoquimioterapia/métodos , Isoindóis , Indóis/farmacologia , Nanopartículas/uso terapêutico , Polímeros , Linhagem Celular Tumoral , Espécies Reativas de Oxigênio/metabolismoRESUMO
Aggregation caused quenching (ACQ) effect can severely inhibit the application of hydrophobic photosensitizers (PSs) bearing planar and rigid structures. Most of the reported cases utilized random-coiled polymers for the in vivo delivery of PSs, which would inevitably aggravate ACQ effect due to the flexible chains. In this work, the role of polymers' secondary structures (especially α-helical conformation) in overcoming the PSs' aggregation is systemically investigated based on the design of α-helical polypeptides bearing tetraphenylporphyrin (TPP) side chains. Atomistic molecular dynamics simulation, fluorescence quantum yield, and reactive oxygen species (ROS) generation yield are evaluated to demonstrate that α-helical polypeptide backbones can significantly boost both fluorescence quantum yield and ROS by suppressing the π-π stacking interaction between TPP units. The enhanced in vitro and in vivo phototoxicity for helical polypeptides also reveal functions of secondary structures in inhibiting ACQ and improving the membrane activity. Successful in vivo photodynamic therapy (PDT) results in mice bearing H22 tumors showed great potentials for further clinical applications.
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Neoplasias , Fotoquimioterapia , Animais , Camundongos , Fármacos Fotossensibilizantes/química , Espécies Reativas de Oxigênio , Fotoquimioterapia/métodos , Neoplasias/tratamento farmacológico , Polímeros/química , Peptídeos/farmacologia , Peptídeos/uso terapêuticoRESUMO
Bangladesh has recently pledged at the 26th Conference of Parties (COP26) to reduce its carbon dioxide emission figures by 22% at the end of 2030. However, since this South Asian country has always turned to fossil fuels for electricity generation purposes, achieving this emission reduction goal is a challenging task for the Bangladesh government. Nevertheless, considering the negative environmental implications associated with the generation and consumption of unclean energy, particularly electricity, it is critically important for Bangladesh to expedite the process of clean transformation of its traditional pollution-intensive power system. Hence, the objective of this study is to dissect the repercussions of hydroelectricity use on Bangladesh's fossil fuel consumption-related carbon dioxide As opposed to the traditional method of quantifying environmental quality using total carbon dioxide emissions, this study considers Bangladesh's annual carbon dioxide emissions generated from the combustion of gas, oil, and coal. Besides, novel Fourier-based econometric methods that effectively handle structural break problems in data are utilized in this study. Based on the results, it is found that up-scaling hydroelectricity consumption levels exert emission-inhibiting effects while greater economic globalization activities are witnessed to boost the emissions. More importantly, hydroelectricity consumption and economic globalization are observed to jointly curb fossil fuel consumption-based emissions of carbon dioxide. Additionally, the results verify the environmental Kuznets curve hypothesis for Bangladesh. Furthermore, financial sector development is found to be effective in reducing the natural gas consumption-related carbon dioxide emissions while urbanization is held responsible for amplifying emissions generated from all three types of fossil fuels. Therefore, considering these findings, the Bangladesh government needs to particularly emphasize scaling up production and consumption of hydroelectricity to decarbonize its economy.
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Dióxido de Carbono , Carvão Mineral , Dióxido de Carbono/análise , Bangladesh , Poluição Ambiental/análise , Gás NaturalRESUMO
Lower-grade gliomas (LGG) are the most common intracranial malignancies that readily evolve to high-grade gliomas and increase drug resistance. Paraptosis is defined as a nonapoptotic form of programmed cell death, which is gradually focused on patients with gliomas to develop treatment options. However, the specific role of paraptosis in LGG and its correlation is still vague. In this study, we first establish the novel paraptosis-based prognostic model for LGG patients. The relevant data of LGG patients were acquired from The Cancer Genome Atlas database, and we found that LGG patients could be divided into three different clusters based on paraptosis via consensus cluster analysis. Through least absolute shrinkage and selection operator regression analysis and multivariate Cox regression analysis, 10-paraptosis-related gene (PRG) signatures (CDK4, TNK2, DSTYK, CDKN3, CCR4, CASP9, HSPA5, RGR, LPAR1, and PDCD6IP) were identified to separate LGG patients into high- and low-risk subgroups successfully. The Kaplan-Meier analysis and time-dependent receiver-operating characteristic showed that the performances of predicting overall survival (OS) were dramatically high. The parallel results were reappeared and verified by using the Chinese Glioma Genome Atlas and Gene Expression Omnibus databases. Independent prognostic analysis and nomogram construction implied that risk scores could be considered the independent factor to predict OS. Enrichment analysis indicated that immune-related biological processes were generally enriched, and different immune statuses were highly infiltrated in high-risk group. We also confirmed the potential relationship of 10-PRG signatures and drug sensitivity of Food and Drug Administration-approved drugs. In summary, our findings provide a novel knowledge of paraptosis status and crucial direction to further explore the role of PRG signatures in LGG.
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Thiocarbamates could be synthesized in green solvents via thiol-dioxazolone modified Lossen rearrangement under transition-metal free, additive free, and mild conditions. Polythiocarbamates were further prepared with excellent self-healing and shape-memory properties, showing great potential in the development of functional materials.
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Compostos de Sulfidrila , TiocarbamatosRESUMO
A metal-, base-, and additive-free N-acylation of sulfoximines was developed under mild conditions using organic photoredox catalyst. This green strategy featured broad substrate scope, good compatibility with air, and high yields (up to 96%). It could be further applied to amino acid modifications and α-keto N-acyl sulfoximine synthesis without any complicated transformations or operations.
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Photodynamic therapy (PDT) is showing great potential in the treatment of cancer diseases, and photosensitizers play crucial roles in absorbing the energy of light and generating reactive oxygen species (ROS) during PDT. Most of the photosensitizers bearing macrocyclic structures have strong hydrophobicity and suffer from the π-π interaction and undesired aggregation caused quenching (ACQ), which severely limit the PDT efficacy. Moreover, the continuous oxygen consumption during PDT also leads to the upregulated expression of hypoxia-inducible factor-1α (HIF-1α), which can aggravate the growth of tumors. To overcome the abovementioned problems, polymerized photosensitizers repelled by flexible thioketal linkers were designed and synthesized using a multicomponent polymerization (MCP) method to afford the poly-porphyrins with high molecular weight (Mw > 20â¯000 g/mol) under room temperature. The ACQ effect could be significantly inhibited by introducing flexible chains and increasing Mw, leading to the improvement in the singlet oxygen quantum yield and phototoxicity simultaneously. An HIF-1α inhibitor, Lificiguat (YC-1) was synthesized as a chemodrug and codelivered with poly-porphyrins to decrease the expression of HIF-1α and inhibit tumor growth under hypoxia. With the synergistic PDT and chemotherapy, poly-porphyrin/YC-1 micelles showed excellent therapeutic antitumor efficacy both in vitro and in vivo.
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Subunidade alfa do Fator 1 Induzível por Hipóxia , Fotoquimioterapia , Porfirinas , Subunidade alfa do Fator 1 Induzível por Hipóxia/antagonistas & inibidores , Fármacos Fotossensibilizantes/farmacologia , Fármacos Fotossensibilizantes/uso terapêutico , Espécies Reativas de Oxigênio , Oxigênio SingleteRESUMO
Obesity is a global chronic disease epidemic that is attributed to the abnormal accumulation of lipids in adipose tissue. Astaxanthin (AST) from Haematococcus pluvialis, a natural carotenoid, exhibits antioxidant, anti-lipogenic, anti-diabetic and other potent effects. Herein, we evaluated the effect of AST to illuminate its efficacy and mechanisms in high-fat diet-fed mice. AST supplementation not only significantly decreased body weight and lipid droplet accumulation in the liver but also modulated liver function and serum lipid levels. Lipidomic analysis revealed that 13 lipids might be potential biomarkers responsible for the effects of AST in lipid reduction, such as total free fatty acids (FFAs), triacylglycerols (TGs) and cholesterol esters (CEs). The gut microbiota sequencing results indicated that AST alleviated HFD-induced gut microbiota dysbiosis by optimizing the ratio of Firmicutes to Bacteroides and inhibiting the abundance of obesity-related pathogenic microbiota while promoting the abundance of probiotics related to glucose and lipid metabolism. In addition, qRT-PCR demonstrated that AST could regulate the gene expressions of the AMPK/SREBP1c pathway by downregulating lipogenesis correlated-genes and upregulating the lipid oxidant related-gene. The present study revealed the new function of AST in regulating lipid metabolism, which provided a theoretical basis for the development of high-quality AST functional food and the application of diet active substances in obesity, as demonstrated in mice.
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Clorófitas , Metabolismo dos Lipídeos/efeitos dos fármacos , Animais , Dieta Hiperlipídica , Disbiose/prevenção & controle , Microbioma Gastrointestinal/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Obesidade/prevenção & controle , Xantofilas/farmacologiaRESUMO
l-Sorbose is an important rare sugar that exists in some natural products and widely used in pharmaceutical and chemical industries. Herein, two simple and practical routes were developed using cheap magnesium (II) for the synthesis of 1,3,4,5-tetra-O-benzyl-l-sorbopyranose from 2,3,4,6-tetra-O-benzyl-d-glucopyranose with high stereoselectivity and yield. The first route involved the intramolecular hydride shift from C5 to the C1 of the glucopyranose precursor. Wittig reagent (PPh3CHCOOBn) was used to combined with Mg(II) to promote this isomerization reaction from d-glucopyranose to l-sorbopyranose in the alternative route.
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Glicosídeos/química , Magnésio/química , Oligossacarídeos/síntese química , Piranos/química , Estrutura Molecular , Oligossacarídeos/química , EstereoisomerismoRESUMO
The aim of this study is to probe a new function of astaxanthin (AST) from Haematococcus pluvialis on chemotherapeutic drug induced liver injury in mice. Doxorubicin-induced liver injury was treated with different doses of AST, and the body weight, food intake, urinalysis, liver function, and oxidative stress indexes were examined. The hepatocyte apoptosis level, pathological sections of liver tissue and the expression of antioxidant related genes were also determined. This study found that DOX could induce serious liver injury through cytotoxicity. AST treatment could decrease the level of liver function indexes (ALT, GOT, ALP and TBil), reduce the concentration of MDA and ROS, and increase the activities of SOD, CAT and GPX in the liver. AST could also repair the damaged hepatocyte in mice with liver injury and reduce the degree of the cellular apoptosis. In addition, AST could interfere with the expression of some related genes in the Keap1/Nrf2 signaling pathway by downregulating the expression of Keap1 and activating the transcription factor Nrf2 via enhancing the level of ERK, which upregulates downstream peroxiredoxins. The present research found and illustrated a new food function of AST, indicating that AST could be used in the therapy of chemotherapy induced side effects.
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Doença Hepática Induzida por Substâncias e Drogas/prevenção & controle , Clorófitas , Cirrose Hepática/prevenção & controle , Substâncias Protetoras/uso terapêutico , Animais , Antineoplásicos/efeitos adversos , Apoptose/efeitos dos fármacos , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Doxorrubicina/efeitos adversos , Hepatócitos/efeitos dos fármacos , Proteína 1 Associada a ECH Semelhante a Kelch/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos ICR , Fator 2 Relacionado a NF-E2/metabolismo , Substâncias Protetoras/administração & dosagem , Substâncias Protetoras/farmacologia , Xantofilas/administração & dosagem , Xantofilas/farmacologia , Xantofilas/uso terapêuticoRESUMO
We report herein a facile synthetic method for converting unactivated (hetero)aryl electrophiles into ß-fluoroethylated (hetero)arenes via nickel-catalyzed reductive cross-couplings. This coupling reaction features the involvement of FCH2 CH2 radical intermediate rather than ß-fluoroethyl manganese species which provides effective solutions to the problematic ß-fluoride side eliminations. The practical value of this protocol is further demonstrated by the late-stage modification of several complex ArCl or ArOH-derived bioactive molecules.
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Polymeric nanoparticles (NPs) have been widely established to deliver most of the hydrophobic chemo-drugs or photosensitizers (PSs) for cancer therapy. However, this strategy is usually hindered by the relatively low drug loading capacity and the undesired toxicity as well as the immunogenicity caused by the nontherapeutic, polymeric carriers. The carrier-free, drug self-delivery systems, in which the chemo-drugs or their prodrugs themselves formed the NPs without the addition of nontherapeutic carriers, have been extensively developed to achieve a high drug loading capacity and low systemic toxicity. However, most of the driving forces to form the NPs were based on the strong hydrophobic interactions, which were the undesired forces for the porphyrin-based hydrophobic PSs due to the parasitic aggregation-caused quenching effect. Herein, the zwitterionic, water-soluble, and reactive oxygen species (ROS)-cleavable poly-photosensitizers (pPSs) were prepared by the polymerization method, which spontaneously introduced different charges associated with the "desired electrostatic effect" and reduced the "undesired aggregation" by separating the PS monomers using flexible and ROS-cleavable linkers. The obtained pPS could be self-assembled into the nanocomplexes based on the electrostatic effect with a high PS loading capacity, improved singlet oxygen generation ability, and efficient phototoxicity. Upon poly(ethylene glycol) (PEG) or hyaluronic acid (HA) coating on the surface, both pPS/PEG and pPS/HA complexes exhibited enhanced stability under physiological environments and excellent in vivo antitumor efficacy. Moreover, HA-coated complexes also exhibited active tumor targeting. Such a polymerization strategy comprehensively addressed the parasitic issues for the hydrophobic PS self-delivery system in the photodynamic therapy area.
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Antineoplásicos/administração & dosagem , Sistemas de Liberação de Medicamentos/métodos , Neoplasias/tratamento farmacológico , Fármacos Fotossensibilizantes/administração & dosagem , Animais , Antineoplásicos/química , Linhagem Celular Tumoral , Portadores de Fármacos/química , Sistemas de Liberação de Medicamentos/instrumentação , Feminino , Humanos , Ácido Hialurônico/química , Interações Hidrofóbicas e Hidrofílicas , Camundongos Endogâmicos BALB C , Camundongos Nus , Nanopartículas/química , Fotoquimioterapia , Fármacos Fotossensibilizantes/química , Polímeros/química , Porfirinas/química , Espécies Reativas de Oxigênio/químicaRESUMO
A novel cascade click/nucleophilic substitution reaction is developed to access 4-heterofunctionalized fully substituted triazolyl-organosulfurs using thiocyanates as both leaving groups and organosulfur precursors. This method features high regioselectivities and board substrate scope. 33 examples are shown to demonstrate the structural diversity through the synthesis of fully substituted triazolyl-organosulfurs including triazolyl-thiocyanates, triazolyl-sulfinylcyanides, triazolyl-thioethers, triazolyl-thiols and triazolyl-disulfides from internal thiocyanatoalkynes.
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The natural planar and rigid structures of most of the hydrophobic photosensitizers (PSs) [such as tetraphenyl porphyrin (TPP)] significantly reduce their loading efficiencies in polymeric nanoparticles (NPs) because of the strong π-π interaction-induced aggregation. This aggregation-caused quenching will further reduce the quantum yield of singlet oxygen (1O2) generation and weaken the efficiency of photodynamic therapy (PDT). In addition, the small molecular PSs exhibit short tumor retention time and tend to be easily cleared once released. Herein, poly(TPP) NPs, prepared by cross-linking of reactive oxygen species degradable, thioketal linkers and TPP derivatives, followed by coprecipitation, were first developed with quantitative loading efficiency (>99%), uniform NP sizes (without aggregation), increased singlet oxygen quantum yield (ΦΔ = 0.79 in dimethyl sulfoxide compared with 0.52 for original TPP), increased in vitro phototoxicity, extended tumor retention time, light-triggered on-demand release, and enhanced in vivo antitumor efficacy, which comprehensively address the multiple issues for most of the PSs in the PDT area.
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Nanopartículas , Neoplasias Experimentais/tratamento farmacológico , Fotoquimioterapia , Fármacos Fotossensibilizantes , Porfirinas , Animais , Feminino , Células HeLa , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Nanopartículas/química , Nanopartículas/uso terapêutico , Fármacos Fotossensibilizantes/química , Fármacos Fotossensibilizantes/farmacologia , Porfirinas/química , Porfirinas/farmacologia , Oxigênio Singlete/metabolismoAssuntos
Neoplasias/terapia , Polieletrólitos/química , Polieletrólitos/metabolismo , Polietilenoimina/química , Espécies Reativas de Oxigênio/metabolismo , Compostos de Sulfidrila/química , Animais , Permeabilidade da Membrana Celular , Sobrevivência Celular/efeitos dos fármacos , Reagentes de Ligações Cruzadas/química , Feminino , Expressão Gênica , Terapia Genética , Células HEK293 , Células HeLa , Humanos , Camundongos Endogâmicos BALB C , Estrutura Molecular , Peso Molecular , Neoplasias/genética , Neoplasias Experimentais , TransfecçãoRESUMO
A method to access various multisubstituted indoles from propargylic alcohols and readily available enol nucleophiles by copper-catalyzed tandem annulation/enol nucleophilic addition has been developed. Compared to the expensive metal catalysts such as platinum, gold, silver, and palladium used previously, the most economical copper(i) catalyst could achieve this reaction efficiently. The fused heterocyclic compounds, pyrrolo[1,2-a] indoles, could be afforded by further transformation of the products. The allyl cation intermediate may be involved in the mechanism.