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11.
《中国化学快报》2023,34(7):107815
Mesoporous carbon supported with transition metals nanoparticles performs desired activities for oxygen reduction reaction (ORR) and clean energy conversion devices such as Zn–air batteries. In this work, we synthesized N-doped mesoporous carbon loaded with cobalt nanoparticles (CoMCN) through self-assembly method. There are sufficient mesopores on the carbon substrate which stem from the pore-forming agent. These mesopores can provide enough accessible active sites and profitable charge/mass transport for ORR. The high content of pyridinic and graphitic N is beneficial for promoting O2 adsorption and reduction. The smaller value of ID/IG indicates the higher degree of graphitization of CoMCN, providing better electronic conductivity. The half-wave potential of CoMCN is 0.865 V in basic solution, which is 24 mV more positive than that of the commercial Pt/C (0.841 V). In addition, CoMCN performs excellent methanol tolerance and stability under both basic and acidic conditions. The Zn–air battery assembled with CoMCN performs the larger power density and open-circuit voltage than the commercial Pt/C-based battery, indicating the potential application in energy conversion systems. This work provides thoughtful ideas for fabricating transition metal nanoparticles based porous carbon for electrocatalysis and metal–air batteries. 相似文献
12.
《中国化学快报》2023,34(6):107927
Proteolysis targeting chimeras (PROTACs) are bifunctional degrader molecules via hijacking the ubiquitin-proteasome system (UPS) to specifically eliminate targeted proteins. PROTACs have gained momentum as a new modality of attractive technologies in the drug discovery landscape, since it allows to degrade disease-related proteins effectively. Although some PROTACs drugs reached the clinical research, they are still facing some bottlenecks and challenges that should not be neglected, such as poor oral bioavailability and potential toxic side effects. To overcome these limitations, herein, we provide an overview of recent strategies for improving the durability of PROTACs by enhancing cell permeability and reducing toxic side effects. Meanwhile, the impact of these strategies on improving oral bioavailability as well as their advantages and drawbacks will also be discussed. This review will give a useful reference toolbox for PROTACs design and further promote its clinical application. 相似文献
13.
《中国化学快报》2023,34(6):108026
Bicyclic peptides, a class of polypeptides with two loops within their structure, have emerged as powerful tools in the development of new peptide drugs. They have the potential to bind to challenged drug targets, with antibody-like affinity and selectivity. Meanwhile, bicyclic peptides possess small molecule-like access to chemical synthesis, which is conducive to large-scale synthesis and screening. In the last five years, bicyclic peptide technology has been increasingly developed, and researchers have carried out a variety of studies to elucidate the potential functions of bicyclic peptides. With the continuous development of synthetic methods and the advances of new technology to build bicyclic peptide libraries, bicyclic peptides are now becoming widely used in the development of new drugs for various diseases. This perspective provides an overview of the structure types, synthesis and applications of bicyclic peptides in current drug development, and our own views on future challenges of bicyclic peptides. 相似文献
14.
《中国化学快报》2023,34(6):107923
The abnormal activation of BRD4 accelerates the progression of acute myeloid leukemia (AML), developing more precise therapeutics to intervene BRD4 promise to be an excellent opportunity to avoid current limitations of chemotherapy in clinic. Herein, a range of small-molecule PROTACs with the privileged 8-methyl-pyrrolo[1,2-a]pyrazin-1(2H)-one scaffold were rationally designed, which harbored different carbon or ethylenedioxy chains to degrade BRD4 mediated by the E3 ubiquitin ligase CRBN. Among them, the most potential B24 exhibited remarkable BRD4 degradation and excellent anti-proliferative activities in MV4-11 cells, with values of DC50 and IC50 for 0.75 nmol/L and 0.4 nmol/L, respectively, which were better than the BRD4 inhibitor (+)-JQ-1. Notably, this compound could time-dependently degrade the target protein in the BRD4-, CRBN-, and proteasome-dependent manner. Besides, B24 dramatically decreased the level of proto-oncogene c-Myc, and induced cell apoptosis by arresting the cell cycle in G0/G1 phase, down-regulating Bcl-2 and up-regulating Bax to amplify apoptotic effectors. This proof-of-concept study also highlighted the feasibility of BRD4-based PROTACs as a more powerful strategy against AML. 相似文献
15.
Weiwei Tang Jun-Jie Shi Wei Liu Xu Lu Bin Li 《Angewandte Chemie (International ed. in English)》2023,62(19):e202301309
A matrix-assisted laser desorption/ionization mass spectrometry imaging (MALDI MSI) assisted genome mining strategy was developed for the discovery of glycosyltransferase (GT) from the root of Platycodon grandiflorum. A di-O-glycosyltransferase PgGT1 was discovered and characterized that is capable of catalyzing platycoside E (PE) synthesis through the attachment of two β-1,6-linked glucosyl residues sequentially to the glucosyl residue at the C3 position of platycodin D (PD). Although UDP-glucose is the preferred sugar donor for PgGT1, it could also utilize UDP-xylose and UDP-N-acetylglucosamine as weak donors. Residues S273, E274, and H350 played important roles in stabilizing the glucose donor and positioning the glucose in the optimal orientation for the glycosylation reaction. This study clarified two key steps involved in the biosynthetic pathway of PE and could greatly contribute to improving its industrial biotransformation. 相似文献
16.
Xuwen Cao Caixia Zhu Qing Hong Xinghua Chen Kaiyuan Wang Prof. Yanfei Shen Prof. Songqin Liu Prof. Yuanjian Zhang 《Angewandte Chemie (International ed. in English)》2023,62(27):e202302463
Ascorbate (H2A) is a well-known antioxidant to protect cellular components from free radical damage and has also emerged as a pro-oxidant in cancer therapies. However, such “contradictory” mechanisms underlying H2A oxidation are not well understood. Herein, we report Fe leaching during catalytic H2A oxidation using an Fe−N−C nanozyme as a ferritin mimic and its influence on the selectivity of the oxygen reduction reaction (ORR). Owing to the heterogeneity, the Fe-Nx sites in Fe−N−C primarily catalyzed H2A oxidation and 4 e− ORR via an iron-oxo intermediate. Nonetheless, trace O2⋅− produced by marginal N−C sites through 2 e− ORR accumulated and attacked Fe-Nx sites, leading to the linear leakage of unstable Fe ions up to 420 ppb when the H2A concentration increased to 2 mM. As a result, a substantial fraction (ca. 40 %) of the N−C sites on Fe−N−C were activated, and a new 2+2 e− ORR path was finally enabled, along with Fenton-type H2A oxidation. Consequently, after Fe ions diffused into the bulk solution, the ORR at the N−C sites stopped at H2O2 production, which was the origin of the pro-oxidant effect of H2A. 相似文献
17.
Qiuyu Li Yunchu Zhang Pengyun Liu Jing Zhong Baihui Gong Prof. Dr. Hequan Yao Prof. Dr. Aijun Lin 《Angewandte Chemie (International ed. in English)》2023,62(4):e202211988
We herein disclose a mild and efficient access to chiral 3-azabicyclo[3.1.0]hexanes via a Pd-catalyzed asymmetric 5-exo-trig cyclization/cyclopropanation/carbonylation of 1,6-enynes. Various nucleophiles, such as alcohols, phenols, amines and water, are well compatible with the reaction system. This reaction forms three C−C bonds, two rings, two adjacent quaternary carbon stereocenters as well as one C−O/C−N bond with excellent regio- and enantioselectivities. The products could be further functionalized to generate a library of 3-azabicyclo[3.1.0]hexane frameworks. 相似文献
18.
《Arabian Journal of Chemistry》2023,16(5):104659
In this article, a series of betulinic acid derivatives (3a ~ 3u, 4a ~ 4e) were synthesized through a stepwise structure optimization and evaluated for their anti-α-glucosidase activities. All synthesized derivatives exhibited stronger anti-α-glucosidase activities (IC50: 0.56 ± 0.05 ~ 3.99 ± 0.23 μM) than betulinic acid (IC50: 7.21 ± 0.58 μM) and acarbose (IC50: 611.45 ± 15.51 μM). Compound 3q presented the outstanding inhibitory activity (IC50: 0.56 ± 0.05 μM), which was ~ 1100 time stronger than that of acarbose. Compound 3q was revealed as a reversible and noncompetitive α-glucosidase inhibitor by inhibitory mechanism assay. Fluorescence spectra, 3D fluorescence and CD spectra results showed that the interaction of compound 3q with α-glucosidase caused the conformational and secondary structure content change of α-glucosidase. Finally, the molecular docking simulated the interaction between compound 3q with α-glucosidase and the physicochemical parameter was assessed using SwissADME software. 相似文献
19.
Chromatographia - In this study, a poly(glycidyl methacrylate) nanoparticle (PGMA NP)-coated column system with two antibiotics as selector was constructed for enantioseparation. The PGMA NP... 相似文献
20.
Xue Chen Kunchao Lu Donghai Lin Yan Li Shiyu Yin Zhiyi Zhang Meihua Tang Guosong Chen 《Electroanalysis》2021,33(2):473-482
Hierarchical porous tubular biochar (PTBC) was prepared by selectively removing lignin simply according to reverse the pyrolysis sequence of cellulose. The properties of the PTBC sample were characterized by XRD, SEM, TEM, Raman spectra, cyclic voltammetry and electrochemical impedance spectroscopy. The electrochemical performances of PTBC modified on the screen-printing electrode illustrated excellent detection of lead ions (lead (II)) in water with the linear range (0.5–120 μg/L) and the detection limit (0.02 μg/L) by in-situ bismuth film square wave anode stripping voltammetry. 相似文献