Publications by authors named "Zhe Chang"

Deuterium labeling has found extensive applications across various research fields, including organic synthesis, drug design, and molecular imaging. Electrocatalytic semi-hydrogenation of alkynes offers a viable route for the synthesis of Z-alkenes, yet it falls short in achieving the semi-deuteration of these compounds. In this study, we report an electrochemical cobalt-catalyzed transfer deuteration reaction that proficiently accomplishes the semi-deuteration of alkynes, yielding Z-configuration deuterated alkene products.

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Background: To evaluate the association between serum uric acid (SUA) levels and metabolic dysfunction-associated steatotic liver disease (MASLD), defined as excessive fat accumulation in the liver accompanied by at least one cardiometabolic risk factor, reflecting metabolic abnormalities associated with the condition, in a Chinese adult population.

Methods: This study included 3829 participants aged ≥ 18 years who underwent abdominal transient elastography and had complete SUA data. SUA was categorized into low, medium, and high tertiles.

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Despite the preliminary success of transition metal-catalyzed [3+2] annulation of amides with olefins, the corresponding radical-type [3+2] annulation remains a laborious challenge. Herein we report the first photoredox-catalyzed radical-type [3+2] annulation of aromatic amides with olefins. We established an approach to generate unprecedented iminium radicals by reducing the oxyiminium intermediates, formed in situ from corresponding amides with TfO, via photoredox catalysis.

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Water-cooled wall tubes are susceptible to high-temperature corrosion during service. Applying high-performance coatings via laser cladding on the tube surfaces can significantly enhance corrosion resistance and extend the service life of the tubes, providing substantial economic advantages. This paper prepared YO/IN625 composite coating by means of high-speed laser cladding.

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To investigate the particle sources before, during, and after the 2022 Beijing Winter Olympic and Paralympic (WOP) in Beijing, ambient particles were passively collected from January to March 2022. The physicochemical properties including morphology, size, shape parameters, and elemental compositions were analyzed by the IntelliSEM EPAS (an advanced computer-controlled scanning electron microscopy [CCSEM] system). Using the user-defined classification rules, 37,174 individual particles were automatically classified into 27 major groups and further attributed to seven major sources based on the source-associated characteristics, including mineral dust, secondary aerosol, combustion/industry, carbonaceous particles, salt-related particles, biological particles, and fiber particles.

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Since the initial report in 1975, the Shono oxidation has become a powerful tool to functionalize the α position of amines, including proline derivatives, by electrochemical oxidation. However, the application of electrochemical Shono oxidations is restricted to the preparation of simple building blocks and homogeneous Shono-type oxidation of proline derivatives remains challenging. The late-stage functionalization at proline residues embedded within peptides is highly important as substitutions about the proline ring are known to affect biological and pharmacological activities.

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Article Synopsis
  • Structure modification of drugs, particularly late-stage functionalization (LSF), is effective for optimizing lead compounds, and this study focused on Cu-catalyzed C-H LSF of 5-nitrofuran drugs.
  • Multiple modifications were performed on the 5-nitrofuran drugs, including hydroxylation, methylation, azidination, cyanation, and arylation, and the antibacterial activities of the new compounds were tested.
  • Among the modified compounds, compounds 1 and 18 showed the highest antibacterial activity, while cell cytotoxicity assays were conducted on potent compounds and the parent drug to assess safety.
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Safe, economical and high-quality storage of huge amount of grain for a longer duration under COVID-19 is a challenge and underground storage is a good alternative due to stable temperature, less cooling consumption and better pest control effect. However, the underground silo has very high requirement of waterproof and the performance of underground silo under combined compression and water pressure was rarely studied. In this study, a new composite structure, polypropylene - concrete wall (PPCW) for underground silo was proposed.

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Regiodivergent alkene functionalization that produces either regioisomer starting from the same raw materials is desirable. Herein, we report a nickel-catalyzed switchable site-selective alkene hydroalkylation. The selection of reaction temperatures leads to protocols that provide regiodivergent hydroalkylated products starting from a single alkene substrate.

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Androgen receptor (AR) serves as a main therapeutic target for prostate cancer (PCa). However, resistance to anti-androgen therapy (SAT) inevitably occurs. Indomethacin is a nonsteroidal anti-inflammatory drug that exhibits activity against prostate cancer.

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Nitrogen heterocycle represents a ubiquitous skeleton in natural products and drugs. Late-stage C(sp)-H bond functionalization of N-heterocycles with broad substrate scope remains a challenge and of particular significance to modern chemical synthesis and pharmaceutical chemistry. Here, we demonstrate copper-catalysed late-stage C(sp)-H functionalizaion of N-heterocycles using commercially available catalysts under mild reaction conditions.

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To increase the reliability and success rate of drug discovery, efforts have been made to increase the C(sp) fraction and avoid flat molecules. sp-Rich enantiopure amines are most frequently encountered as chiral auxiliaries, synthetic intermediates for pharmaceutical agents and bioactive natural products. Streamlined construction of chiral aliphatic amines has long been regarded as a paramount challenge.

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It is well known that Markowitz's mean-variance model is the pioneer portfolio selection model. The mean-variance model assumes that the probability density distribution of returns is normal. However, empirical observations on financial markets show that the tails of the distribution decay slower than the log-normal distribution.

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Objective: To establish the normal parameters of fetal lung development at different gestational ages and to study their correlation with gestational age, thereby providing clinicians with a noninvasive method for assessing fetal lung maturity.

Methods: Two hundred eight cases with pregnancy of 22 to 39 weeks plus 6 days were divided into 18 groups according to gestational age. Ultrasound Doppler was used to measure the relevant parameters of fetal pulmonary development, including right pulmonary left and right diameter, right pulmonary upper and lower diameter, right pulmonary anterior and posterior diameter, right pulmonary area, thoracic area, inner diameter of fetal main pulmonary artery, and Doppler velocity curve parameters of main pulmonary artery: systolic acceleration time (AT), ejection time (ET), AT/ET.

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We developed an efficient method for synthesis of substituted -benzoylindole via Pd(II)-catalyzed C-H functionalization of substituted -(2-allylphenyl)benzamide. The reaction showed a broad substrate scope (including -acetyl and -Ts substrates) and substituted indoles were obtained in good to excellent yields. The most distinctive feature of this method lies in the high selectivity for -benzoylindole over benzoxazine, and this is the first example of Pd(II)-catalyzed synthesis of substituted -benzoylindole.

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For the development of high-performance gas sensors, ultrafast response and high selectivity are critical requirements for many practical applications. An alternative strategy is to employ hierarchical nanostructured materials in gas sensors. In this work, we report newly synthesized TiO hexagonal nanosheets with a hierarchical porous structure, which demonstrate an ultrafast gas response and high selectivity toward acetone vapor for the first time.

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With the globalisation of Chinese medicine (CM), the local CM education institutions were established in many other countries outside of China. These CM education institutions have formed a new mode in CM education after integrating with local culture, law and national conditions. This article takes New Zealand CM education institutions as an example to discuss the characteristics of CM education under the British education system, aiming to provide ideas on CM education in China and other countries.

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In this work, we study the characteristics of self-pulsing in a polarization-maintained fiber amplifier operated with different linewidths based on white noise source phase modulation. It indicates that the self-pulsing is almost simultaneous with the stimulated Brillouin scattering process, and its threshold is increasing near-linearly with the linewidth. By optimizing the laser structure, the threshold of self-pulsing increases by a factor of 1.

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The emergence of drug resistance in bacterial pathogens is a growing clinical problem that poses difficult challenges in patient management. To exacerbate this problem, there is currently a serious lack of antibacterial agents that are designed to target extremely drug-resistant bacterial strains. Here we describe the design, synthesis and antibacterial testing of a series of 40 novel indole core derivatives, which are predicated by molecular modeling to be potential glycosyltransferase inhibitors.

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Recently, there has been a renewed interest in the natural-products-inspired drugs. Quebrachitol (QCT) is one of naturally occurring optically active cyclitols that has now received considerable attention. Until the last decade, it came to be a starting point for the lead discovery.

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Tankyrases (TNKS), key transmitters in the Wnt signaling pathway which is very conservative in evolution, are vital targets as they are overexpressed widely in many cancers. In this work, 5 inhibitors with novel structures have been discovered and validated using the ligand-based (pharmacophore) virtual screening, docking study, and Luciferase reporter assays for Wnt signaling. Among them, PYL-1, in particular, was the most potent inhibitor with an IC value of 9.

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It is an urgent need to develop new drugs for Mycobacterium tuberculosis (Mtb), and the enzyme, dihydrofolate reductase (DHFR) is a recognised drug target. The crystal structures of methotrexate binding to mt- and h-DHFR separately indicate that the glycerol (GOL) binding site is likely to be critical for the function of mt-DHFR selective inhibitors. We have used in silico methods to screen NCI small molecule database and a group of related compounds were obtained that inhibit mt-DHFR activity and showed bactericidal effects against a test Mtb strain.

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Activation of K-ras and inactivation of p16 are the most frequently identified genetic alterations in human pancreatic epithelial adenocarcinoma (PDAC). Mouse models engineered with mutant K-ras and deleted p16 recapitulate key pathological features of PDAC. However, a human cell culture transformation model that recapitulates the human pancreatic molecular carcinogenesis is lacking.

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Purpose: The most common genetic lesions in pancreatic ductal adenocarcinoma (PDAC) have been identified. However, significant gaps still exist in our understanding of how such genetic alterations act in concert to induce PDAC development. In this study, we investigated the mechanism of tumorigenic transformation in the immortalized human pancreatic ductal epithelial (HPDE) cell line by sequentially introducing PDAC signature alterations into this cell line.

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