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1.
Angew Chem Int Ed Engl ; : e202406016, 2024 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-38703020

RESUMO

Metabolic acidosis-induced kidney injury (MAKI) is asymptomatic and lack of clinical biomarkers in early stage, but rapidly progresses to severe renal fibrosis and ultimately results in end-stage kidney failure. Therefore, developing rapid and noninvasive strategies direct responsive to renal tubular acidic microenvironment rather than delayed biomarkers are essential for timely renoprotective interventions. Herein, we develop pH-responsive luminescent gold nanoparticles (p-AuNPs) in the second near-infrared emission co-coated with 2,3-dimethylaleic anhydride conjugated ß-mercaptoethylamine and cationic 2-diethylaminoethanethiol hydrochloride, which showed sensitive pH-induced charge reversal and intrarenal self-assembly for highly sensitive and long-time (~24 h) imaging of different stages of MAKI. By integrating advantages of pH-induced intrarenal self-assembly and enhanced interactions between pH-triggered positively charged p-AuNPs and renal tubular cells, the early- and late-stage MAKI could be differentiated rapidly within 10 min post-injection (p.i.) with contrast index (CI) of 3.5 and 4.3, respectively. The corresponding maximum CI could reach 5.1 and 9.2 at 12 h p.i., respectively. Furthermore, p-AuNPs were demonstrated to effectively real-time monitor progressive recovery of kidney injury in MAKI mice after therapy, and also exhibit outstanding capabilities for drug screening. This pH-responsive strategy showed great promise for feedback on kidney dysfunction progression, opening new possibilities for early-stage diagnosis of pH-related diseases.

2.
Chem Sci ; 15(20): 7502-7514, 2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38784726

RESUMO

The exploitation of new reactive species and novel transformation modes for their synthetic applications have significantly promoted the development of synthetic organic methodology, drug discovery, and advanced functional materials. α-Iminyl radical cations, a class of distonic ions, exhibit great synthetic potential for the synthesis of valuable molecules. For their generation, radical conjugate addition to α,ß-unsaturated iminium ions represents a concise yet highly challenging route, because the in situ generated species are short-lived and highly reactive and they have a high tendency to cause radical elimination (ß-scission) to regenerate the more stable iminium ions. Herein, we report a new transformation mode of the α-iminyl radical cation, that is to say, 1,5-hydrogen atom transfer (1,5-HAT). Such a strategy can generate a species bearing multiple reactive sites, which serves as a platform to realize (asymmetric) relay annulations. The present iron/secondary amine synergistic catalysis causes a modular assembly of a broad spectrum of new structurally fused pyridines including axially chiral heterobiaryls, and exhibits good functional group tolerance. A series of mechanistic experiments support the α-iminyl radical cation-induced 1,5-HAT, and the formation of several radical species in the relay annulations. Various synthetic transformations of the reaction products demonstrate the usefulness of this relay annulation protocol for the synthesis of significant molecules.

3.
Angew Chem Int Ed Engl ; : e202404129, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38651974

RESUMO

Designing luminophores bright in both isolate species and aggregate states is of great importance in many emerging cutting-edge applications. However, the conventional luminophores either emit in isolate species but quench in aggregate state or emit in aggregate state but darken in isolate species. Here we demonstrate that the precise regulation of noncovalent interactions can realize luminophores bright in both isolate species and aggregate states. It is firstly discovered that the intra-cluster interaction enhances the emission of atomically precise Au25(pMBA)18 (pMBA=4-mercaptobenzoic acid), a nanoscale luminophore, while the inter-cluster interaction quenches the emission. The emission enhancing strategies are then well-designed by both introducing exogenous substances to block inter-cluster interaction and surface manipulation of Au25(pMBA)18 at the molecular level to enhance intra-cluster interaction, opening new possibilities to controllably enhance the luminophore's photoluminescence in both isolate species and aggregate states in different phases including aqueous solution, solid state and organic solvents.

4.
Org Lett ; 26(7): 1358-1363, 2024 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-38345019

RESUMO

A metal-free three-component protocol that combines a hydroxylamine-Passerini reaction and hetero-Cope rearrangement was realized, which enables the modular assembly of a wide range of structurally new and interesting 2-aminoanilines bearing an α-hydroxyamide substructure.

5.
Mol Breed ; 44(1): 4, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38225950

RESUMO

Improving quality is an essential goal of rice breeding and production. However, rice quality is not solely determined by genotype, but is also influenced by the environment. Phenotype plasticity refers to the ability of a given genotype to produce different phenotypes under different environmental conditions, which can be a representation of the stability of traits. Seven quality traits of 141 hybrid combinations, deriving from the test-crossing of 7 thermosensitive genic male sterile (TGMS) and 25 restorer lines, were evaluated at 5 trial sites with intermittent sowing of three to five in Southern China. In the Yangtze River Basin, it was observed that delaying the sowing time of hybrid rice combinations leads to an improvement in their overall quality. Twelve parents were identified to have lower plasticity general combing ability (GCA) values with increased ability to produce hybrids with a more stable quality. The parents with superior quality tend to exhibit lower GCA values for plasticity. The genome-wide association study (GWAS) identified 13 and 15 quantitative trait loci (QTLs) associated with phenotype plasticity and BLUP measurement, respectively. Notably, seven QTLs simultaneously affected both phenotype plasticity and BLUP measurement. Two cloned rice quality genes, ALK and GL7, may be involved in controlling the plasticity of quality traits in hybrid rice. The direction of the genetic effect of the QTL6 (ALK) on alkali spreading value (ASV) plasticity varies in different cropping environments. This study provides novel insights into the dynamic genetic basis of quality traits in response to different cropping regions, cultivation practices, and changing climates. These findings establish a foundation for precise breeding and production of stable and high-quality rice. Supplementary Information: The online version contains supplementary material available at 10.1007/s11032-024-01442-3.

6.
Angew Chem Int Ed Engl ; 63(11): e202316900, 2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38258485

RESUMO

Transcytosis-based tubular reabsorption of endogenous proteins is a well-known energy-saving pathway that prevents nutrient loss. However, utilization of this well-known reabsorption pathway for the delivery of exogenous nanodrugs remains a challenge. In this study, using the surface mimic strategy of a specific PEPT1/2-targeted Gly-Sar peptide as a ligand, renal-clearable luminescent gold nanoparticles (P-AuNPs) were developed as protein mimics to investigate the transcytosis-based tubular reabsorption of exogenous substances. By regulating the influential factors (H+ content in tubular lumens and PEPT1/2 transporter counts in tubular cells) of Gly-Sar-mediated transcytosis, the specific and efficient interaction between P-AuNPs and renal tubular cells was demonstrated both in vitro and in vivo. Efficient transcellular transportation significantly guided the reabsorption of P-AuNPs back into the bloodstream, which enhanced the blood concentration and bioavailability of nanoparticles, contributing to high-contrast tumor imaging.


Assuntos
Nanopartículas Metálicas , Nanopartículas , Neoplasias , Humanos , Ouro/química , Nanopartículas Metálicas/química , Transcitose , Rim/metabolismo , Neoplasias/metabolismo
7.
Blood Cancer J ; 13(1): 178, 2023 12 05.
Artigo em Inglês | MEDLINE | ID: mdl-38052803

RESUMO

Realgar-Indigo naturalis formula (RIF), an oral traditional Chinese medicine mainly containing Realgar (As4S4), is highly effective in treating adult acute promyelocytic leukemia (APL). However, the treatment efficacy and safety of RIF have not been verified in pediatric patients. SCCLG-APL group conducted a multicenter randomized non-inferiority trial to determine whether intravenous arsenic trioxide (ATO) can be substituted by oral RIF in treating pediatric APL. Of 176 eligible patients enrolled, 91 and 85 were randomized to ATO and RIF groups, respectively. Patients were treated with the risk-adapted protocol. Induction, consolidation, and 96-week maintenance treatment contained all-trans-retinoic acid and low-intensity chemotherapy, and either ATO or RIF. The primary endpoint was 5-year event-free survival (EFS). The secondary endpoints were adverse events and hospital days. After a median 6-year follow-up, the 5-year EFS was 97.6% in both groups. However, the RIF group had significantly shorter hospital stays and lower incidence of infection and tended to have less cardiac toxicity. All 4 relapses occurred within 1.5 years after completion of maintenance therapy. No long-term arsenic retentions were observed in either group. Substituting oral RIF for ATO maintains treatment efficacy while reducing hospitalization and adverse events in treating pediatric APL patients, which may be a future treatment strategy for APL.


Assuntos
Arsênio , Leucemia Promielocítica Aguda , Criança , Humanos , Arsênio/efeitos adversos , Trióxido de Arsênio/efeitos adversos , Arsenicais/efeitos adversos , Leucemia Promielocítica Aguda/tratamento farmacológico , Resultado do Tratamento , Tretinoína/uso terapêutico
8.
Angew Chem Int Ed Engl ; 62(50): e202314896, 2023 12 11.
Artigo em Inglês | MEDLINE | ID: mdl-37929305

RESUMO

Ultrasmall luminescent gold nanoparticles (AuNPs) with excellent capabilities to cross biological barriers offer great promise in designing intelligent model nanomedicines for investigating structure-property relationships at the subcellular level. However, the strict surface controllability of ultrasmall AuNPs is challenging because of their small size. Herein, we report a facile in situ method for precisely controlling DNA aptamer valences on the surface of luminescent AuNPs with emission in the second near-infrared window using a phosphorothioate-modified DNA aptamer, AS1411, as a template. The discrete DNA aptamer number of AS1411-functionalized AuNPs (AS1411-AuNPs, ≈1.8 nm) with emission at 1030 nm was controlled in one aptamer (V1), two aptamers (V2), and four aptamers (V4). It was then discovered that not only the tumor-targeting efficiencies but also the subcellular transport of AS1411-AuNPs were precisely dependent on valences. A slight increase in valence from V1 to V2 increased tumor-targeting efficiencies and resulted in higher nucleus accumulation, whereas a further increase in valence (e.g., V4) significantly increased tumor-targeting efficiencies and led to higher cytomembrane accumulation. These results provide a basis for the strict surface control of nanomedicines in the precise regulation of in vivo transport at the subcellular level and their translation into clinical practice in the future.


Assuntos
Aptâmeros de Nucleotídeos , Nanopartículas Metálicas , Neoplasias , Humanos , Ouro , DNA
9.
RSC Adv ; 13(47): 33053-33060, 2023 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-37954425

RESUMO

In recent years, additive manufacturing techniques have been used to fabricate 3D titanium (Ti)-based scaffolds for production of desirable complex shapes. However, insufficient osteointegration of porous Ti-based scaffolds can elicit long-term complications (e.g., aseptic loosening) and need further revision surgery. In this study, a magnesium (Mg)-incorporating tantalum (Ta) coating was deposited on a 3D Ti6Al4V scaffold using a sol-gel method for enhancing its osteogenic properties. To evaluate the biofunction of this surface, bone mesenchymal stem cells and rabbit femoral condyle were used to assess the cell response and bone ingrowth, respectively. Ta2O5 coatings and Mg-incorporating Ta2O5 coatings were both homogeneously deposited on porous scaffolds. In vitro studies revealed that both coatings exhibit enhanced cell proliferation, ALP activity, osteogenic gene expression and mineralization compared with the uncoated Ti6Al4V scaffold. Especially for Mg-incorporating Ta2O5 coatings, great improvements were observed. In vivo studies, including radiographic examination, fluorochrome labeling and histological evaluation also followed similar trends. Also, bone ingrowth to scaffolds with Mg-incorporating Ta2O5 coatings exhibited the most significant increase compared with uncoated and Ta2O5 coated scaffolds. All the above results indicate that Mg-doped Ta2O5 coatings are an effective tool for facilitating osteointegration of conventional porous Ti6Al4V scaffolds.

10.
Med Dosim ; 2023 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-37858458

RESUMO

This study aims to establish a delineation guideline for the contouring of the hypoglossal nerve by dividing the nerve into different segments, and to test the possibility of a radiation dose reduction to the hypoglossal nerve in NPC patients receiving radiotherapy. Twenty NPC patients were selected arbitrarily. The hypoglossal nerves were delineated using anatomic landmarks and divided into the cisternal, intracanalicular, carotid, and transverse segments. The tumor coverage by radiation and dose-volume parameters of the nerve with and without various dose constraints to the hypoglossal nerve were compared. The hypoglossal nerve, which is invisible on CT images, can be delineated accurately with the assistance of several anatomic landmarks. Without a dose constraint to the hypoglossal nerve, the carotid space, intracanalicular, and transverse segments had high radiation dose-volumes. The dose-volume to the nerve, however, can be reduced when the nerve was defined and a dose constraint was given. The delineation of the hypoglossal nerve with its different segments is feasible. The carotid space, intracanalicular, and transverse segments received the highest dose, where the nerve damage was most likely located. The dose to the nerve can be reduced to less than 70 Gy using the intensity-modulated radiotherapy technique.

11.
Eur J Med Res ; 28(1): 334, 2023 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-37689799

RESUMO

BACKGROUND: Treatment for cancer patients presenting with acute myocardial infarction (AMI) remains challenging. The objective of the study was to investigate the safety and efficiency of drug eluting balloon (DEB) versus drug eluting stent (DES) in this high-risk group. METHODS: Between 1st January 2017 and 1st January 2022, cancer patients admitted to Beijing Chaoyang Hospital with AMI were retrospectively enrolled. The primary endpoint was major adverse cardiovascular event (MACE). The secondary endpoints included major bleeding events, heart failure and cardiac complications. RESULTS: A total of 164 cancer patients presenting with AMI were included in the final analysis. Patients treated with DEB had a numerically lower rate of MACE than those treated with DES during a median follow-up of 21.8 months (22.9% vs. 37.1%, p = 0.23). Patients treated with DEB had a trend towards lower rate of major bleeding events than patients treated with DES (6.3% vs. 18.1%, HR 2.96, 95% CI [0.88, 9.92], p = 0.08). There were no significant differences between the two groups with regards to the rate of heart failure (4.2% vs. 9.5%, p = 0.32) and cardiac complications (0.0% vs. 2.6%, p = 0.56). CONCLUSIONS: The present study demonstrated that in cancer patients with AMI, DEB had a trend towards lower rate of major bleeding events and a numerically lower rate of MACE compared with DES.


Assuntos
Stents Farmacológicos , Insuficiência Cardíaca , Infarto do Miocárdio , Neoplasias , Humanos , Stents Farmacológicos/efeitos adversos , Estudos Retrospectivos , Infarto do Miocárdio/cirurgia , Insuficiência Cardíaca/etiologia , Insuficiência Cardíaca/terapia , Hospitalização , Neoplasias/complicações
12.
Oncologist ; 28(11): e995-e1004, 2023 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-37265056

RESUMO

BACKGROUND: The disease burden of pancreatic cancer in East Asia is at a high level, but the epidemiological characteristics of pancreatic cancer in the region have not been systematically studied. METHOD: Joinpoint analysis was used to identify average annual percentage change (AAPC) and annual percentage change (APC) in mortality. Age-period-cohort models were used to analyze age-period cohort effects across countries. Bayesian age-period-cohort (BAPC) analysis was used to project the burden of disease for 2020-2030. RESULTS: Pancreatic cancer mortality in males in Japan (2012-2019, APC = -0.97) and Korea (2012-2019, APC = -0.91) has shown a decreasing trend since 2012 (P < .05). However, China (2016-2019, APC = 3.21), Mongolia (2015-2.019, APC = 2.37), and North Korea (2012-2019, APC = 0.47) showed a significant increase in pancreatic cancer in both genders (P < .05). Risk factors for pancreatic cancer in East Asia remained largely stable between 2010 and 2019. Mortality of pancreatic cancer due to smoking began to decline in areas with high socio-demographic index (SDI), and mortality of pancreatic cancer due to high body mass index and high fasting plasma glucose increased with SDI. The age-standardized mortality for pancreatic cancer in Chinese males is expected to exceed that of Japan and South Korea by 2030, but the disease burden of pancreatic cancer in Japan and South Korea remains at extremely high levels. CONCLUSION: Economically developed countries are beginning to show a decreasing trend in the burden of pancreatic cancer disease, and developing countries are experiencing a rapid increase in the age-standardized death rate (ASDR) of pancreatic cancer.


Assuntos
Neoplasias Pancreáticas , Feminino , Humanos , Masculino , Teorema de Bayes , Ásia Oriental , Japão , Fatores de Risco , Anos de Vida Ajustados por Qualidade de Vida
13.
Materials (Basel) ; 16(7)2023 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-37049200

RESUMO

The enhancement of the durability of sulfoaluminate cement (CSA) in marine environments is of great importance. To this end, an investigation was carried out involving the placement of CSA concrete in the tidal zone of Zhairuoshan Island, Zhoushan, China, and subjected to a 20-month marine tidal exposure test. The comparison was made with ordinary Portland cement (OPC) concrete to evaluate the effectiveness of the former. The test findings indicate that the compressive strength of both types of concrete is reduced by seawater dry-wet cycling, and the porosity of the surface concrete is increased. However, the compressive strength of CSA concrete is observed to be more stable under long-term drying-wetting cycles. When the ettringite in the CSA surface concrete is decomposed due to carbonization and alkalinity reduction, its products will react with Ca2+ and SO42- in seawater to regenerate ettringite to fill in the concrete pores, making the concrete strength more stable and hindering chlorine penetration. Furthermore, CSA concrete exhibits a higher capillary absorption capacity than OPC concrete, which results in chloride accumulation on its surface. However, the diffusion capacity of chloride in CSA concrete is significantly lower than that in OPC concrete.

14.
J Org Chem ; 88(7): 4863-4874, 2023 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-36946256

RESUMO

We describe a synergistic Cu/secondary amine catalysis for skeletal transformation of an oxindole core into a quinolinone skeleton, which generates several structurally new pyridine-fused quinolinones. The synergistic reactions allow expansion of a five-membered lactam ring by radical cation-triggered C-C bond cleavage and enable a further intramolecular cyclization with the aim to construct totally distinct core skeletons.

15.
Anal Chem ; 95(11): 5061-5068, 2023 03 21.
Artigo em Inglês | MEDLINE | ID: mdl-36908024

RESUMO

Biomarker-activatable luminescent probes with high sensitivity and specificity show great promise in advanced bioimaging applications. However, the lack of stable biomarkers at an early stage is currently a major obstacle for sensitive early disease imaging. Herein, we develop a facile in vivo ligand exchange strategy to achieve renal-clearable activatable luminescent gold nanoparticles (AuNPs), which are independent of biomarkers for sensitive and long-time imaging of early kidney injury. Significantly activated emission in the second near-infrared region (∼1026 nm) is realized from the ligand exchange of triphenylphosphine-3,3',3″-trisulfonic acid (TPPTS)-coated AuNPs (∼1.4 nm, TPPTS-AuNPs) with quantitative amounts of glutathione (GSH). The abundant GSH in cells, particularly in liver sinusoids, is then demonstrated successfully to activate the emission of TPPTS-AuNPs with an extremely low background for both cell imaging and in vivo visualization of visceral organs (e.g., liver and kidneys). In addition, the in vivo GSH-exchanged TPPTS-AuNPs show enhanced interactions with acidic renal tubular epithelial cells, resulting in sensitive (contrast index, ∼3.9) and long-time (>6.5 h) noninvasive monitoring of acidosis-induced early kidney injury. This facile ligand exchange strategy opens new possibilities for designing activatable luminescent probes independent of biomarkers for earlier disease diagnosis and treatment.


Assuntos
Ouro , Nanopartículas Metálicas , Ligantes , Rim/diagnóstico por imagem , Glutationa
16.
J Cardiovasc Dev Dis ; 10(1)2023 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-36661924

RESUMO

BACKGROUND: The incidence of acute myocardial infarction (AMI) in the younger population has been increasing gradually in recent years. The objective of the present study is to investigate the safety and effectiveness of drug-eluting balloons (DEBs) in young patients with AMI. METHODS: All consecutive patients with AMI aged ≤ 45 years were retrospectively enrolled. The primary endpoint was a device-oriented composite endpoint (DOCE) of cardiac death, target vessel myocardial infarction (MI), or target lesion revascularization (TLR). The secondary study endpoints included heart failure and major bleeding events. RESULTS: A total of 276 young patients presenting with AMI were finally included. The median follow-up period was 1155 days. Patients treated with DEBs had a trend toward a lower incidence of DOCEs (3.0% vs. 11.0%, p = 0.12) mainly driven by the need for TLR (3.0% vs. 9.1%, p = 0.19) than those treated with DESs. No significant differences between the two groups were detected in the occurrence of cardiac death (0.0% vs. 0.5%, p = 0.69), MI (0.0% vs. 1.4%, p = 0.40), heart failure (0.0% vs. 1.9%, p = 0.39), or major bleeding events (1.5% vs 4.8%, p = 0.30). Multivariate regression analysis showed that DEBs were associated with a trend toward a lower risk of DOCEs (HR 0.13, 95% CI [0.02, 1.05], p = 0.06). CONCLUSIONS: The findings of the present study suggested that DEBs might be a potential treatment option in young patients with AMI. A larger scale, randomized, multicenter study is required to investigate the safety and effectiveness of DEBs in this setting.

17.
Angew Chem Int Ed Engl ; 62(10): e202214720, 2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36652185

RESUMO

A precise understanding of nano-bio interactions in the sub-nanometer regime is necessary for advancements in nanomedicine. However, this is currently hindered by the control of the nanoparticle size in the sub-nanometer regime. Herein, we report a facile in situ Mn2+ -guided centrifugation strategy for the synthesis of large-scale ultrasmall gold nanoparticles (AuNPs) with a precisely controlled size gradient at the sub-nanometer regime. With the discovery that [Mn(OH)]+ , especially metallic manganese (Mn0 @[Mn(OH)]+ ) nanoparticles, could selectively interact with larger AuNPs through synergistic coordination and hydrogen bonding to form aggregates, we also realized the fast (<1 h) synthesis of water-soluble atomically precise Au25 with high yields (>56 %). We further demonstrated that sub-nanometer size differences (approximately 0.5 nm) significantly alter non-specific phagocytosis of AuNPs in the reticuloendothelial system macrophages, elimination rate, and nanotoxicology.

18.
Nanotechnology ; 33(49)2022 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-35977454

RESUMO

Solar-driven photoelectrochemical (PEC) water splitting for hydrogen generation is regarded as a sustainable strategy to relieve fossil resource issue. However, its PEC conversion efficiency still suffers from the low light absorption and high electron-hole recombination. Herein, we report 1D/2D hierarchical heterostructured photoelectrode constructed by ordered ZnO nanorod array and intimately attached ultra-thin Hematene (thickness of monolayer: 1-2 nm) for effective PEC water oxidation with visible light irradiation. The onset potential of Hematene/ZnO NRs photoanode (0.28 V versus RHE) for PEC water oxidation has an obvious negative shift compared with that of ZnO NRs (0.32 V versus RHE) indicating the enhanced PEC kinetics. Furthermore, reduced charge transport resistance (18.82 KΩ cm-2), a high carrier density of 9.03 × 1018cm-3and the resulting significantly enhanced incident photon-to-current efficiency enhancement compared with ZnO NRs photoanode were obtained for Hematene/ZnO NRs photoanode. All these were ascribed to the formation of large built-in electric field which was arising from the charge redistribution at the ZnO and Hematene interface, and the band alignment engineering between the components. In summary, such interfacial engineering may inspire the future development of 1D/2D hierarchical heterostructured photoanodes in the field of PEC water splitting.

19.
Chem Sci ; 13(24): 7283-7288, 2022 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-35799821

RESUMO

Bridged tetracyclic nitrogen scaffolds are found in numerous biologically active molecules and medicinally relevant structures. Traditional methods usually require tedious reaction steps, and/or the use of structurally specific starting materials. We report an unprecedented, iminyl radical-triggered relay annulation from oxime-derived peresters and azadienes, which shows good substrate scope and functional group compatibility, and can deliver various bridged aza-tetracyclic compounds with complex molecular topology and four contiguous stereogenic centers (dr > 19 : 1) in a single operation. This transformation represents the first example of trifunctionalization of iminyl radicals through simultaneous formation of one C-N and two C-C bonds. DFT calculation studies were conducted to obtain an in-depth insight into the reaction pathways, which revealed that the reactions involved an interesting 1,6-hydrogen atom transfer process.

20.
Nanotechnology ; 33(5)2021 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-34673549

RESUMO

A novel carbon nitride particle-decorated three-dimensional porous nickel foam (CN/NF) was fabricated by a simple thermal polymerization deposition method for photoelectrochemical glucose detection. In this PEC sensing system, the synergetic effect of the photoactive CN and conductive current collector NF with multi-charge transfer channels contributed to the efficient separation of photoexcited charge carriers. The CN/NF electrode showed an excellent response for glucose detection and good anti-interference properties. A wide linear detection up to 1000µM and sensitivity of 460.2µA cm-2mM-1were obtained. This work provides a new strategy for designing binder-free electrodes for PEC sensing.

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