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1.
Adv Mater ; : e2406653, 2024 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-39113338

RESUMEN

The solution aggregation structure of conjugated polymers is crucial to the morphology and resultant optoelectronic properties of organic electronics and is of considerable interest in the field. Precise characterizations of the solution aggregation structures of organic photovoltaic (OPV) blends and their temperature-dependent variations remain challenging. In this work, the temperature-dependent solution aggregation structures of three representative high-efficiency OPV blends using small-angle X-ray/neutron scattering are systematically probed. Three cases of solution processing resiliency are elucidated in state-of-the-art OPV blends. The exceptional processing resiliency of high-efficiency PBQx-TF blends can be attributed to the minimal changes in the multiscale solution aggregation structure at elevated temperatures. Importantly, a new parameter, the percentage of acceptors distributed within polymer aggregates (Ф), for the first time in OPV blend solution, establishes a direct correlation between Ф and performance is quantified. The device performance is well correlated with the Kuhn length of the cylinder related to polymer aggregates L1 at the small scale and the Ф at the large scale. Optimal device performance is achieved with L1 at ≈30 nm and Ф within the range of 60 ± 5%. This study represents a significant advancement in the aggregation structure research of organic electronics.

2.
Acta Crystallogr C Struct Chem ; 80(Pt 8): 440-447, 2024 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-39046815

RESUMEN

Ruxolitinib {RUX; systematic name: (3R)-3-cyclopentyl-3-[4-(7H-pyrrolo[2,3-d]pyrimidin-4-yl)-1H-pyrazol-1-yl]propanenitrile, C17H18N6} is an orally bioavailable JAK1/2 inhibitor approved for treating intermediate- or high-risk myelofibrosis (MF) and high-risk polycythemia vera (PV). Recent patents claim that RUX can exist in many different forms, information for which is important for the clinical utilization of RUX, especially for the formulation and bioavailability of the drug. But there has been no detailed study on its forms so far. Herein crystals of RUX and its dihydrate (RUX-2H; C17H18N6·2H2O) and phosphate (RUX-P; systematic name: 4-{1-[(1R)-2-cyano-1-cyclopentylethyl]-1H-pyrazol-4-yl}-7H-pyrrolo[2,3-d]pyrimidin-3-ium dihydrogen phosphate, C17H19N6+·H2PO4-) were prepared successfully and their structures studied in detail for the first time. Our study shows that the three crystals of RUX differ in the orientation of the pyrimidine ring relative to the pyrazole ring of the RUX molecule, and in their hydrogen-bond interactions. The water molecules in RUX-2H and the dihydrogen phosphate anion in RUX-P enrich the hydrogen-bond networks in these forms. The expected proton transfer occurs in RUX phosphate and the protonated N atom is engaged in a charge-assisted hydrogen bond with the counter-anion. Hydrogen-bonding interactions dominate in the crystal packing of the three forms. The detailed conformations and packing of the three forms were compared through the calculation of both Hirshfeld surfaces and fingerprint plots.


Asunto(s)
Enlace de Hidrógeno , Janus Quinasa 1 , Janus Quinasa 2 , Nitrilos , Fosfatos , Pirazoles , Pirimidinas , Pirimidinas/química , Pirimidinas/farmacología , Pirazoles/química , Pirazoles/farmacología , Nitrilos/química , Cristalografía por Rayos X , Janus Quinasa 2/antagonistas & inhibidores , Janus Quinasa 2/química , Janus Quinasa 2/metabolismo , Fosfatos/química , Janus Quinasa 1/antagonistas & inhibidores , Janus Quinasa 1/química , Estructura Molecular , Inhibidores de Proteínas Quinasas/química , Inhibidores de Proteínas Quinasas/farmacología , Humanos
3.
J Affect Disord ; 362: 485-492, 2024 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-39009318

RESUMEN

BACKGROUND: Major depression (MD) is recurrent and devastating mental disease with a high worldwide prevalence. Mounting evidence suggests neuroinflammation triggers cellular immune dysregulation, characterized by increased proportions of circulating monocytes, and T helper 17 cells and proinflammatory cytokines, thereby increasing susceptibility to MD. However, there is ambiguity in the findings of clinical studies that investigate CD4+ T regulatory (Treg) cells in MD. METHODS: The proportion of CD4+ Treg cell from blood mononuclear cells was examined using flow cytometry in healthy controls (HCs: n = 96) and patients with first (FEMD: n = 62) or recurrent (RMD: n = 41) disease episodes of MD at baseline (T0; hospital admission) and after a two-week antidepressant treatment (T14). All participants underwent comprehensive neuropsychological assessments. RESULTS: The initial scores on emotional assessments in patients with MD significantly differed from those of HCs. Both FEMD and RMD patients exhibited a significant decrease in CD4+ Treg cell proportion at baseline compared to HCs. Treg cell proportion rose significantly from T0 to T14 in FEMD patients, who responded to antidepressant therapy, whereas no significant changes were observed in FEMD patients in non-response as well as RMD patients. The improvement of 24-item Hamilton Depression Scale was correlate with changes of Treg cell proportion from T0 to T14 in FEMD patients in response, and the change in Treg cell proportion over a 14-day period exhibited an AUC curve of 0.710. CONCLUSIONS: A decrease in the proportion of CD4+ Treg cells points towards immune system abnormalities in patients with MD. Furthermore, our finding suggests that the immune activation state varies across different stages of depression.


Asunto(s)
Antidepresivos , Trastorno Depresivo Mayor , Linfocitos T Reguladores , Humanos , Trastorno Depresivo Mayor/inmunología , Trastorno Depresivo Mayor/tratamiento farmacológico , Masculino , Femenino , Adulto , Linfocitos T Reguladores/inmunología , Linfocitos T Reguladores/efectos de los fármacos , Antidepresivos/uso terapéutico , Persona de Mediana Edad , Citometría de Flujo
4.
Anal Chem ; 96(25): 10451-10458, 2024 06 25.
Artículo en Inglés | MEDLINE | ID: mdl-38860917

RESUMEN

Rapid and sensitive RNA detection is of great value in diverse areas, ranging from biomedical research to clinical diagnostics. Existing methods for RNA detection often rely on reverse transcription (RT) and DNA amplification or involve a time-consuming procedure and poor sensitivity. Herein, we proposed a CRISPR/Cas12a-enabled amplification-free assay for rapid, specific, and sensitive RNA diagnostics. This assay, which we termed T7/G4-CRISPR, involved the use of a T7-powered nucleic acid circuit to convert a single RNA target into numerous DNA activators via toehold-mediated strand displacement reaction and T7 exonuclease-mediated target recycling amplification, followed by activating Cas12a trans-cleavage of the linker strands inhibiting split G-Quadruplex (G4) assembly, thereby inducing fluorescence attenuation proportion to the input RNA target. We first performed step-by-step validation of the entire assay process and optimized the reaction parameters. Using the optimal conditions, T7/G4-CRISPR was capable of detecting as low as 3.6 pM target RNA, obtaining ∼100-fold improvement in sensitivity compared with the most direct Cas12a assays. Meanwhile, its excellent specificity could discriminate single nucleotide variants adjacent to the toehold region and allow species-specific pathogen identification. Furthermore, we applied it for analyzing bacterial 16S rRNA in 40 clinical urine samples, exhibiting a sensitivity of 90% and a specificity of 100% when validated by RT-quantitative PCR. Therefore, we envision that T7/G4-CRISPR will serve as a promising RNA sensing approach to expand the toolbox of CRISPR-based diagnostics.


Asunto(s)
Sistemas CRISPR-Cas , G-Cuádruplex , Sistemas CRISPR-Cas/genética , Humanos , Exodesoxirribonucleasas/metabolismo , Exodesoxirribonucleasas/química , ARN/análisis , ARN/metabolismo , Técnicas de Amplificación de Ácido Nucleico , Proteínas Asociadas a CRISPR/metabolismo , Proteínas Bacterianas , Endodesoxirribonucleasas
5.
Chemistry ; : e202402247, 2024 Jun 26.
Artículo en Inglés | MEDLINE | ID: mdl-38923595

RESUMEN

Vinylidene ortho-quinone methides (VQMs) have been proven to be versatile and crucial intermediates in the catalytic asymmetric reaction in last decade, and thus have drawn considerable concentrations on account of the practical application in the construction of enantiomerically pure functional organic molecules. However, in comparison to the well established chiral Brønsted base-catalyzed asymmetric reaction via VQMs, chiral Brønsted acid-catalyzed reaction is rarely studied and there is no systematic summary to date. In this review, we summarize the recent advances in the chiral Brønsted acid-catalyzed asymmetric reaction via VQMs according to three types of reactions: a) intermolecular asymmetric nucleophilic addition to VQMs; b) intermolecular asymmetric cycloaddition of VQMs; c) intramolecular asymmetric cyclization of VQMs. Finally, we put forward the remained challenges and opportunities for potential breakthroughs in this area.

6.
Sci Adv ; 10(26): eado5460, 2024 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-38941466

RESUMEN

The nanoscale morphology of the photoactive layer notably impacts the performance of organic solar cells (OSCs). Conventional methods to tune the morphology are typically chemical approaches that adjust the properties (such as solubility and miscibility) of the active components including donor, acceptor, and/or additive. Here, we demonstrate a completely different approach by applying an external electric field (EEF) on the active layer during the wet coating. The EEF-coating method is perfectly compatible with an ambient blade coating using environmentally friendly solvents, which are essential requirements for industrial production of OSCs. A record 18.6% efficiency is achieved using the EEF coating, which is the best value for open-air, blade-coated OSCs to date. Our findings suggest broad material applicability and attribute-enhanced performance to EEF-induced fiber formation and long-range ordering of microstructures of acceptor domains. This technique offers an effective method for producing high-performance OSCs, especially suited for industry OSC production based on open-air printing.

7.
J Colloid Interface Sci ; 672: 486-496, 2024 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-38852351

RESUMEN

The instability in the structural integrity caused by interfacial issues is commonly regarded as the primary drawback of Ni-rich layered cathode materials (LiNixCoyMn1-x-yO2, where x  ≥ 0.8), which must be addressed before their commercial application. Herein, a novel multiple-function surface modification strategy is proposed based on the single crystal structure to in-situ achieve the construction of a coating layer and surface doping with Ce element to enhance the structural stability of the LiNi0.88Co0.09Mn0.03O2 (NCM). Notably, the introduction of Ce-O bonding adjusts the local oxygen coordination to achieve a more stabilized structure of the oxygen framework, which inhibits the evolution of lattice oxygen and enhances conductivity. Additionally, by benefiting from the in-situ synthesized coating layer of LixCeO2, the occurrence of side reactions on the surface is effectively alleviated, resulting in a reduction in electrode polarization. Combined with comprehensive electrochemical tests, it is confirmed that the improved electrochemical performance originates from the reduction of the detrimental H2-H3 phase transition and enhanced conductivity. As expected, the modified material with 1 wt% content of Ce (NCM@Ce) exhibits a high initial discharge capacity of 196.3 mAh g-1 with a capacity retention of 79.7 % after 200 cycles, and its energy density reaches 574.3 Wh kg-1 after 200 cycles.

8.
Chemistry ; 30(41): e202401389, 2024 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-38779789

RESUMEN

Transition metal-catalyzed epoxidation of carbonyl compounds through carbonyl ylides represents a highly effective method for synthesizing a diverse range of valuable epoxides. This review offers an in-depth overview of the latest developments in inter- and intramolecular epoxidation reactions involving metal carbenes and carbonyl compounds, encompassing both racemic to enantioselective transformations. These catalytic epoxidations are reviewed by highlighting their product selectivity, diversity and applicability, and the related mechanistic rationale is showcased where possible.

9.
Org Lett ; 26(18): 3861-3866, 2024 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-38679881

RESUMEN

Catalytic cyclization of enynes is an efficient approach for the preparation of cyclic compounds, and a large variety of four- to six-membered rings could be synthesized using this method. However, it has been rarely employed for the construction of medium- and large-sized rings. Herein, we describe a copper-catalyzed cycloisomerization of ene-ynamides through a [2 + 2] cyclization/electrocyclic ring opening cascade, leading to the atom-economical assembly of indole-fused medium- and large-sized rings in moderate to excellent yields under mild reaction conditions. Importantly, the synthetic utility of this reaction was demonstrated by the convenient synthesis of iprindole.

10.
Cell Death Dis ; 15(4): 244, 2024 Apr 04.
Artículo en Inglés | MEDLINE | ID: mdl-38575607

RESUMEN

The immunosuppressive microenvironment caused by several intrinsic and extrinsic mechanism has brought great challenges to the immunotherapy of pancreatic cancer. We identified GFPT2, the key enzyme in hexosamine biosynthesis pathway (HBP), as an immune-related prognostic gene in pancreatic cancer using transcriptome sequencing and further confirmed that GFPT2 promoted macrophage M2 polarization and malignant phenotype of pancreatic cancer. HBP is a glucose metabolism pathway leading to the generation of uridine diphosphate N-acetylglucosamine (UDP-GlcNAc), which is further utilized for protein O-GlcNAcylation. We confirmed GFPT2-mediated O-GlcNAcylation played an important role in regulating immune microenvironment. Through cellular proteomics, we identified IL-18 as a key downstream of GFPT2 in regulating the immune microenvironment. Through CO-IP and protein mass spectrum, we confirmed that YBX1 was O-GlcNAcylated and nuclear translocated by GFPT2-mediated O-GlcNAcylation. Then, YBX1 functioned as a transcription factor to promote IL-18 transcription. Our study elucidated the relationship between the metabolic pathway of HBP in cancer cells and the immune microenvironment, which might provide some insights into the combination therapy of HBP vulnerability and immunotherapy in pancreatic cancer.


Asunto(s)
Interleucina-18 , Neoplasias Pancreáticas , Humanos , Glicosilación , Interleucina-18/metabolismo , Neoplasias Pancreáticas/patología , Proteínas/metabolismo , Vías Biosintéticas , Hexosaminas , Microambiente Tumoral , Proteína 1 de Unión a la Caja Y/metabolismo , Glutamina-Fructosa-6-Fosfato Transaminasa (Isomerizadora)/genética
11.
Nat Commun ; 15(1): 2232, 2024 Mar 12.
Artículo en Inglés | MEDLINE | ID: mdl-38472194

RESUMEN

Site- and stereoselective C-H functionalization is highly challenging in the synthetic chemistry community. Although the chemistry of vinyl cations has been vigorously studied in C(sp3)-H functionalization reactions, the catalytic enantioselective C(sp3)-H functionalization based on vinyl cations, especially for an unactivated C(sp3)-H bond, has scarcely explored. Here, we report an asymmetric copper-catalyzed tandem diyne cyclization/unactivated C(sp3)-H insertion reaction via a kinetic resolution, affording both chiral polycyclic pyrroles and diynes with generally excellent enantioselectivities and excellent selectivity factors (up to 750). Importantly, this reaction demonstrates a metal-catalyzed enantioselective unactivated C(sp3)-H functionalization via vinyl cation and constitutes a kinetic resolution reaction based on diyne cyclization. Theoretical calculations further support the mechanism of vinyl cation-involved C(sp3)-H insertion reaction and elucidate the origin of enantioselectivity.

12.
Org Lett ; 26(10): 2051-2056, 2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-38436250

RESUMEN

A one-pot gold-catalyzed acyl migration followed by ytterbium-catalyzed asymmetric Friedel-Crafts alkylation is disclosed, leading to the rapid synthesis of chiral dihydrocarbazoles and dihydrodibenzofuran in generally moderate to good overall yields with good to excellent enantioselectivities. The gold-catalyzed acyl migration of propargyl acetates generates α-ylidene-ß-diketones with high E/Z ratios, which are then subjected to the ytterbium-catalyzed asymmetric Friedel-Crafts alkylation without any purification. Importantly, this protocol provides a new type of substrate for asymmetric Friedel-Crafts alkylation.

13.
Asia Pac J Oncol Nurs ; 11(4): 100382, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38495640

RESUMEN

Objective: This study identified the potential subgroups of fear of cancer recurrence (FCR) in family caregivers (FCs) of patients with hematologic malignancies receiving chemotherapy, as well as exploring factors associated with subgroups. Methods: This was a cross-sectional study involving 206 pairs of participating patients with hematologic malignancies receiving chemotherapy and their FCs. Using Mplus 8.3 to perform the latent profile analysis of FCs' FCR, the FCs' burden, quality of life, psychological resilience, and anxiety as well as their demographic characteristics were compared between the subgroups, with a logistic regression analysis being applied to examine the factors associated with the FCR subgroups. Results: A total of 206 FCs were classified into two subgroups: "a low level of FCR" (Class 1, 65.4%) and "a high level of FCR" (Class 2, 34.6%). Quality of life, anxiety, and frequency of chemotherapy were significantly associated with the two subgroups. Conclusions: FCs of patients with hematologic malignancy receiving chemotherapy had two FCR subgroups, "a low level of FCR" and "a high level of FCR", in association with quality of life, anxiety, and frequency of chemotherapy. These findings provide the theoretical foundations for screening the FCR factor of FCs and conducting interventions for them.

14.
Adv Mater ; 36(21): e2313098, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38340310

RESUMEN

Despite the rapid development in the performances of organic solar cells (OSCs), high-performance OSC modules based on green printing are still limited. The severe Coffee-ring effect (CRE) is considered to be the primary reason for the nonuniform distribution of active layer films. To solve this key printing problem, the cosolvent strategy is presented to deposit the active layer films. The guest solvent Mesitylene with a higher boiling point and a lower surface tension is incorporated into the host solvent o-XY to optimize the rheological properties, such as surface tension and viscosity of the active layer solutions. And the synergistic effect of inward Marangoni flow generation and solution thickening caused by the cosolvent strategy can effectively restrain CRE, resulting in highly homogeneous large-area active layer films. In addition, the optimized crystallization and phase separation of active layer films effectively accelerate the charge transport and exciton dissociation of devices. Consequently, based on PM6:BTP-eC9 system, the device prepared with the co-solvent strategy shows the a power conversion efficiency of 17.80%. Moreover, as the effective area scales to 1 and 16.94 cm2, the recorded performances are altered to 16.71% and 14.58%. This study provides a universal pathway for the development of green-printed high-efficiency organic photovoltaics.

15.
Drug Discov Today ; 29(3): 103906, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38309689

RESUMEN

Antimetastatic agents are highly desirable for cancer treatment because of the severe medical challenges and high mortality resulting from tumor metastasis. Having demonstrated antimetastatic effects in numerous in vitro and in vivo studies, migration inhibitors present significant opportunities for developing a new class of anticancer drugs. To provide a useful overview on the latest research in migration inhibitors, this article first discusses their therapeutic significance, targetable proteins, and developmental avenues. Subsequently it reviews over 20 representative migration inhibitors reported in recent journals in terms of their inhibitory mechanism, potency, and potential clinical utility. The relevance of the target proteins to cellular migratory function is focused on as it is crucial for assessing the overall efficacy of the inhibitors.


Asunto(s)
Antineoplásicos , Humanos , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Movimiento Celular , Metástasis de la Neoplasia/tratamiento farmacológico , Línea Celular Tumoral
16.
Front Neurosci ; 18: 1293962, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38419660

RESUMEN

Introduction: When constructing machine learning and deep neural networks, the domain shift problem on different subjects complicates the subject independent electroencephalography (EEG) emotion recognition. Most of the existing domain adaptation methods either treat all source domains as equivalent or train source-specific learners directly, misleading the network to acquire unreasonable transfer knowledge and thus resulting in negative transfer. Methods: This paper incorporates the individual difference and group commonality of distinct domains and proposes a multi-source information-shared network (MISNet) to enhance the performance of subject independent EEG emotion recognition models. The network stability is enhanced by employing a two-stream training structure with loop iteration strategy to alleviate outlier sources confusing the model. Additionally, we design two auxiliary loss functions for aligning the marginal distributions of domain-specific and domain shared features, and then optimize the convergence process by constraining gradient penalty on these auxiliary loss functions. Furthermore, the pre-training strategy is also proposed to ensure that the initial mapping of shared encoder contains sufficient emotional information. Results: We evaluate the proposed MISNet to ascertain the impact of several hyper-parameters on the domain adaptation capability of network. The ablation experiments are conducted on two publically accessible datasets SEED and SEED-IV to assess the effectiveness of each loss function. Discussion: The experimental results demonstrate that by disentangling private and shared emotional characteristics from differential entropy features of EEG signals, the proposed MISNet can gain robust subject independent performance and strong domain adaptability.

17.
Small ; 20(26): e2309685, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38238155

RESUMEN

As a mainstream technology for recycling spent lithium-ion batteries, direct regeneration is rapidly developed due to its high efficiency and green characteristics. However, efficient reuse of spent LiNixCoyMn1- x - yO2 cathode is still a significant challenge, as the rock salt/spinel phase on the surface hinders the Li replenishment and phase transformation to the layered structure. In this work, the fundamental understanding of the repair mechanism is confirmed that the oxidizing atmosphere is the crucial factor that can greatly improve the rate and degree of phase restoration. Particularly, a ternary-component molten salt system (LiOH-Li2CO3-LiNO3) is proposed for direct regeneration of LiNi0.5Co0.2Mn0.3O2 (NCM523), which can in situ generate the strong oxidizing intermediate of superoxide radicals. Additionally, it shows a liquid-like reaction environment at a lower temperature to acceclerate the transport rate of superoxide-ions. Therefore, the synergistic effect of LiOH-Li2CO3-LiNO3 system can strengthen the full restoration of rock salt/spinel phases and achieve the complete Li-supplement. As anticipated, the regenerated NCM523 delivers a high cycling stability with a retention of 91.7% after 100 cycles, which is even competitive with the commercial NCM523. This strategy provides a facile approach for the complete recovery of layer structure cathode, demonstrating a unique perspective for the direct regeneration of spent lithium-ion batteries.

18.
Angew Chem Int Ed Engl ; 63(11): e202318595, 2024 Mar 11.
Artículo en Inglés | MEDLINE | ID: mdl-38224211

RESUMEN

Achieving a more balanced charge transport by morphological control is crucial in reducing bimolecular and trap-assisted recombination and enhancing the critical parameters for efficient organic solar cells (OSCs). Hence, a facile strategy is proposed to reduce the crystallinity difference between donor and acceptor by incorporating a novel multifunctional liquid crystal small molecule (LCSM) BDTPF4-C6 into the binary blend. BDTPF4-C6 is the first LCSM based on a tetrafluorobenzene unit and features a low liquid crystal phase transition temperature and strong self-assembly ability, conducive to regulating the active layer morphology. When BDTPF4-C6 is introduced as a guest molecule into the PM6 : Y6 binary, it exhibits better compatibility with the donor PM6 and primarily resides within the PM6 phase because of the similarity-intermiscibility principle. Moreover, systematic studies revealed that BDTPF4-C6 could be used as a seeding agent for PM6 to enhance its crystallinity, thereby forming a more balanced and favourable charge transport with suppressed charge recombination. Intriguingly, dual Förster resonance energy transfer was observed between the guest molecule and the host donor and acceptor, resulting in an improved current density. This study demonstrates a facile approach to balance the charge mobilities and offers new insights into boosting the efficiency of single-junction OSCs beyond 20 %.

19.
Oncol Lett ; 27(2): 50, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38192659

RESUMEN

[This retracts the article DOI: 10.3892/ol.2015.3525.].

20.
Org Lett ; 26(3): 631-635, 2024 Jan 26.
Artículo en Inglés | MEDLINE | ID: mdl-38214532

RESUMEN

A gold-catalyzed, nucleophile-controlled cascade reaction of N-(2-azidophenyl-ynyl)methanesulfonamides with nitriles and water is described that provides structurally diverse 5H-pyrimido[5,4-b]indoles and 2-benzylidene-3-indolinones in good to excellent yields. Mechanistic studies indicate that the ß-sulfonamido-α-imino gold carbene is the key intermediate which is generated through the gold-catalyzed cyclization of N-(2-azidophenyl-ynyl)methanesulfonamides and undergoes formal [4 + 2] cascade annulation with nitriles and intramolecular SN2' type reaction with water, respectively.

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