SYNTHESIS-STUTTGART
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2013
·Vol. 45
·期 16
·2234-2240
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IF 2.5
Wenbin Lu,Zhuye Liang,Yuwei Zhang,Fan Wu,Qun Qian,Hegui Gong
Alkyl aryl ketones were prepared on a gram scale by the nickel-catalyzed reductive coupling of alkyl iodides with aroyl chlorides. When scaled up 30-fold, this reaction shows a comparable coupling efficiency to the previously reported reaction performed under small-scale conditions. The mild and convenient reaction conditions show excellent tolerance to a range of functional groups and provide the ketones in good to excellent yields.
研究领域:
有机化学
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合成化学
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DOI
高影响因子
TETRAHEDRON LETTERS
·
2020
·
IF 2.275
Haibo Zhu,Yingying Zhang,Yishuai Liu,Liu Yang,Zongbo Xie,Guofang Jiang,Zhang-Gao Le
A practical and efficient approach adopting transition-metal-free cross-coupling of sulfonyl hydrazides with benzyl ammonium salts has been developed to synthesize benzyl sulfones using Cs 2 CO 3 as base under mild conditions. The protocol employs stable and easy to handle coupling partners, and is endowed with good substrate compatibility, leading to functional benzyl sulfones in good yields.
研究领域:
有机化学
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合成化学
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高影响因子
Animals
·
2019
·Vol. 10
·期 1
·74
·
IF 1.832
Jiakun Shen,Aneela Perveen,Niaz Kaka,Zhaojian Li,Pengyuan Dai,Chunmei Li
Simple SummaryThis study investigated the effects of maternal T-2 toxin exposure on the development of testis in the mice offspring. The detrimental effects were assessed by testicular weight, antioxidant capacity, and testosterone synthesis and secretion. Studies have shown that the toxin carried by the mother has bad effects on the testicular development of offspring at puberty, affecting the antioxidant system and testosterone synthesis in the testis, but the maternal exposure of T-2 toxin had no significant impact on the testes of offspring after sexual maturity, suggesting the recovery of reproductive function.AbstractT-2 toxin, the most toxic member of trichothecene mycotoxin, is widely distributed in cereals, and has been extensively studied, but few studies focus on the toxicity of maternal exposure to offspring. This study focused on the effects of maternal exposure to T-2 toxin (during gestation and lactation) on the testicular development of mice offspring. Dams were orally administered with T-2 toxin at 0, 0.005, or 0.05 mg/kg body weight from the late stage of gestation to the end of lactation. Testicular samples of the mice offspring were collected on the postnatal day 21, 28, and 56. The results showed significant decreases in body weight and testicular weight on the postnatal day 28. Moreover, significant inhibition of antioxidant system and testosterone synthesis was detected on the postnatal day 28. Furthermore, there were significant decreases in the gene expression levels ofStARand3β-HSD, which are involved in testosterone synthesis. In general, present results demonstrated that maternal exposure to T-2 toxin during gestation and lactation led to bad effects on the capacity of antioxidant system and inhibited testosterone synthesis in testes during pre-puberty with no significant effects on post-puberty.Keywords:maternal exposure;oxidative stress;T-2 toxin;testicular development;testosterone synthesis
研究领域:
毒理学
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生殖生物学
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内分泌学
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PubMed
高影响因子
CyTA-Journal of Food
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2018
·
IF 1.371
Liang Li,Ying Ma
Methyl ketones can be formed by the metabolism of intermediate products of β-oxidation by enzymes. In this article, the effect of soluble saccharides on the activity of key enzymes involved in methyl ketone synthesis in L. lactis was studied by detecting the relationship between soluble saccharides and enzyme activity. The results showed that glucose, fructose, sucrose, lactose and galactose could promote the growth of L. lactis. Glucose induced the activity of enoyl-coenzyme A (CoA) hydratase but inhibited the activity of β-hydroxyacyl-CoA dehydrogenase. Fructose induced the activities of acyl-CoA dehydrogenase and enoyl-CoA hydratase while maintaining the activity of β-hydroxyacyl-CoA dehydrogenase. Sucrose induced the activities of enoyl-CoA hydratase and β-hydroxyacyl-CoA dehydrogenase and maintained the activity of thiolase. Lactose also induced enoyl-CoA hydratase activity. Galactose induced enoyl-CoA hydratase activity and maintained thiolase activity. Glucose, lactose, fructose and galactose induced thioesterase activity. The data showed fructose and lactose could inhibit thiolase activity and induce thioesterase activity, which would be beneficial to methyl ketone synthesis, so fructose and lactose were the best soluble saccharides, followed by galactose, glucose and sucrose. A positive and significant correlation was found between thioesterase activity and enoyl-CoA hydratase activity (p < 0.01). In summary, the β-oxidation system of L. lactis is related to sugar metabolism.
研究领域:
微生物学
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生物化学
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高影响因子
JOURNAL OF APPLIED PHYCOLOGY
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2022
·Vol. 34
·期 3
·1709-1719
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IF 3.404
Li Jing,Pang Shaojun,Su Li,Shan Tifeng
Phlorotannins are among the most important defensive molecules in kelp. They have been majorly identified in brown algae so far. Type III polyketide synthase (PKS) is regarded as one of the enzymes catalyzing a major step in the biosynthetic pathway of phlorotannins. In this study, a type III PKS gene ( sjPKS1 ) is characterized from the economic brown alga Saccharina japonica sporophyte. It contains 7 exons and 6 introns. The sjPKS1 open reading frame consists of 1245 nucleotides encoding a protein of 414 amino acids. The sjPKS1 are 87%, 83%, and 82% identical to that of Ectocarpus siliculosus , Sargassum binderi , and Sargassum fusiforme at the nucleotide level, respectively. While the amino acid sequences of sjPKS1 share more than 90% identity to that of the three brown algae species. The sjPKS1 expression at 200 µmol photons m −2 s −1 was significantly higher than at 20 and 50 µmol photons m −2 s −1 in sporophytic seedlings, so did the content of soluble phlorotannins inside the plants. Seven motifs in response to light are identified in the 5′ flanking region of sjPKS1 and two potential transcription factors are predicted by screening yeast one-hybrid library.
研究领域:
海洋植物学
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分子生物学
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遗传学
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高影响因子
JOURNAL OF CATALYSIS
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2022
·
IF 8.047
Yuan Yu,Chun-Xiu Liu,Xin-Yue Fan,Yun-Jie Wei,Ru-De Lin,Yao Yao,Ming-Liang Shi,Na Wang,Xiao-Qi Yu
High-efficiency photo-enzymatic synthesis of chalcone chemicals was achieved by tandem catalysis based on the photocatalytic oxidation of porphyrin-based metal organic frameworks (MOFs) confined copper nanoclusters and the non-specific catalytic activity of hydrolases. A series of photocatalysts were successfully synthesized and the Cu nanoparticles (NPs) were loaded on the materials by in-situ reduction of Cu 2+ . Subsequently, in situ oxidation of benzyl alcohol and aldol reaction catalyzed in tandem by Cu@PCN-222(M) and hydrolase were used as template reactions and the reaction conditions were systematically studied. 20 chalcone derivatives were successfully synthesized (yield up to 98 %). Finally, the optical properties difference of photocatalysts were studied by spectroscopic and electrochemical analysis. The reaction system used greener benzyl alcohol as the reaction substrate and was driven by visible light under O 2 . This method has good yield and recovery performance, which provides a new strategy for the construction of MOF-enzyme combined catalytic system.
研究领域:
化学
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生物化学
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DOI
高影响因子
Nature Communications
·
2024
·Vol. 15
·期 1
·1-12
·
IF 14.7
Ma Xinlong,Yin Haibin,Pu Zhengtian,Zhang Xinyan,Hu Sunpei,Zhou Tao,Gao Weizhe,Luo Laihao,Li Hongliang,Zeng Jie
Acetone serves as an important solvent and building block for the chemical industry, but the current industrial synthesis of acetone is generally accompanied by the energy-intensive and costly cumene process used for phenol production. Here we propose a sustainable route for acetone synthesis via propane wet reforming at a moderate temperature of 350 o C with the use of platinum-tin nanoparticles supported on γ-aluminium oxide (PtSn/γ-Al 2 O 3 ) as catalyst. We achieve an acetone productivity of 858.4 μmol/g with a selectivity of 57.8% among all carbon-based products and 99.3% among all liquid products. Detailed spectroscopic and controlled experiments reveal that the acetone is formed through a tandem catalytic process involving propene and isopropanol as intermediates. We also demonstrate facile ketone synthesis via wet reforming with the use of different alkanes ( e.g ., n-butane, n-pentane, n-hexane, n-heptane, and n-octane) as substrates, proving the wide applicability of this strategy.
研究领域:
化学工程
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催化科学
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能源化工
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PubMed
高影响因子
CHEMICAL ENGINEERING & TECHNOLOGY
·
2016
·Vol. 39
·期 10
·1867-1874
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IF 2.385
Jun Mei,Zhirong Chen,Shenfeng Yuan,Jianyong Mao,Haoran Li,Hong Yin
A kinetic study on isophorone synthesis via self-condensation of supercritical acetone catalyzed by aqueous KOH in a tubular flow reactor was conducted. The intention was to improve the isophorone selectivity, with the main approach to reduce the by-products higher-boiling than isophorone. A higher isophorone selectivity was obtained with increased reaction temperature. The structures of main products were determined by gas chromatography-mass spectrometry and nuclear magnetic resonance analysis. The key reaction pathways and a corresponding kinetic model were proposed. The fitted apparent activation energies indicated the reason of isophorone selectivity improvement in that high temperature favors reversion of reversible by-products.
研究领域:
化学工程
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催化反应
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有机化学
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DOI
高影响因子
Catalysis Science & Technology
·
2021
·Vol. 11
·期 21
·7072-7082
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IF 6.119
Xiao-Chao Chen,Kai-Chun Zhao,Yin-Qing Yao,Yong Lu,Ye Liu
The development of an efficient methodology to transform CO2 into valuable chemicals has attracted increasing attention concerning the challenging issues of CO2-utilization. Herein, an efficient approach for the preparation of oxazolidinones from CO2, primary (aliphatic/aromatic) amines and 1,2-dichloroethane (or its derivatives) catalyzed by DBU organo-superbase was achieved with yields of 47–97% under mild conditions (80–100 °C, 12 h, 1.0 MPa CO2). Control experiments demonstrated that the formation of an ion-pair carbamate salt intermediate IS-B derived from the reaction of CO2, DBU (catalyst) and an amine (substrate) was the key step for this three-component reaction. The available DBU–amine–CO2 adduct intermediate (like IS-B-2) with fair stability will evolve into the thermodynamically stable product oxazolidinones upon attack of 1,2-dichloroethane (or its derivatives), along with the regeneration of the DBU catalyst. Alternatively, the decomposition of the DBU–aryl amine–CO2 adduct (like IS-B-1) with relatively poor stability also could result in the competitive substitution reaction of 1,2-dichloroethane (or its derivatives) with the aryl amine. This work provides insights into synergetic CO2-activation by the DBU-catalyst and a nucleophilic amine-substrate via the formation of robust carbamate salt intermediates responsible for the final production of oxazolidinones.
研究领域:
有机化学
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环境化学
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DOI
高影响因子
CATALYSIS LETTERS
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2024
·
IF 2.3
Chen Bojiang,Wu Jianping,Rukhsana,Xiang Fei-Yong,Zhao Fu-Gang,Liu Xunshan,Liang Xuezheng,Shen Yong-Miao
Both the alkyl sulfonic acid and phenyl sulfonic acid groups were incorporated onto a hypercrosslinked porous polymer through copolymerization and post-sulfonation to form novel PDVB-SO 3 H-SO 3 H catalyst. The porous polymer based solid acid. PDVB-SO 3 H-SO 3 H was applied to the cayaltic synthesis of thioacetal (thioketal) at room temperature. N 2 adsorption isotherm experiments demonstrated that the catalyst possessed the significantly high BET surface area. In comparison with conventional homogeneous acid catalysts such as sulfuric acid and p-toluenesulfonic acid, the porous polymer based solid acid. PDVB-SO 3 H-SO 3 H showed several noteworthy advantages, including remarkable catalytic activity at room temperature and mild reaction conditions, broad substrates scope, high specific surface area, exceptional acid strength, flexible hydrophobicity, and excellent recyclability. These exceptional features make the polymer a highly promising candidate for diverse industrial applications. Graphical Abstract
研究领域:
材料化学
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催化化学
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高影响因子
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
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2024
·
IF 7.7
Wenwen Pei,Xuewen Zhang,Yan Zeng,Jiao Li,Ziyi Li,Jiangang Yang,Xinjun Du,Yueming Zhu,Yuanxia Sun
α-Hydroxyketones, which have significant industrial applications, can be sustainably synthesized through the oxidation of secondary alcohols using secondary alcohol dehydrogenase (SADH). However, the activity of the SADH oxidation reaction is generally low, making it unsuitable for large-scale production. In this study, a rational design approach was employed to computationally engineer SADH derived from Ogataea parapolymorpha ( Op SADH), significantly enhancing its oxidation activity towards ( R )-1,2-propanediol (PDO). The mutant M2 (S222T/S316A) exhibited a 14.2-fold increase in specific enzyme activity compared to the wild type (WT) and was employed as a catalyst for high-concentration hydroxyacetone production, facilitated by an NAD + regeneration system. By applying an appropriate Zn 2+ ion force field in molecular dynamics (MD) simulations, it was found that two mutation sites could stabilize the conformations of NAD + and PDO, thereby revealing the molecular mechanism behind the enhanced activity of this metalloenzyme mutant. Notably, we first uncovered the dynamic mechanism by which four key residues (Cys39, His75, Glu76, and Glu175) and PDO within the active pocket contribute to the formation of coordination bonds with Zn 2+ . The findings of this study provide robust support for researching the catalytic mechanisms and dynamics processes of metalloenzymes.
研究领域:
生物化学
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酶工程
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计算生物学
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DOI
PubMed
高影响因子
ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY
·
2025
·
IF 6.1
Qing Zhao,Lingling Zhai,Yangyang Song,Mujiao Li,You Yang,Jian Zhao
The toxic effect of Polystyrene Microplastics (PS-MPs) on leydig cells were found in male mice, but the toxic mechanism was not clear. The PS-MPs exposure mice model and cell model were established in this study to explore the leydig cells toxic mechanism. In vivo study, the leydig cells toxicity in male mice was evaluated exposed to PS-MPs for 28 days. And found that the sperm density, mobility and testosterone (T) level decreased, and the sperm malformation rate and malondialdehyde level increased. PS-MPs exposure impaired the function of male reproduction. The results also showed that the levels of testosterone-producing proteins (StAR, P450scc,3β-HSD and CYP17A1) decreased, apoptosis signaling pathways (Bax/Bcl-2, Caspase-8 and Caspase-12) were activated and endoplasmic reticulum stress (GRP78/p-PERK/CHOP) occurred in male mice exposed to PS-MPs. In vitro study, TM3 cells (leydig cells) were treated with 50, 100 and 200 μg/mL of PS-MPs for 24 h. And we found that PS-MPs exposure reduced the cell viability and the level of T, increased reactive oxygen species (ROS) level in TM3 cells. PS-MPs exposure impaired the function of the leydig cells. Further testing revealed that PS-MPs could activate GRP78/p-PERK/CHOP pathway, aggrandized endoplasmic reticulum stress in the leydig cells, then increased apoptosis level, and induced testosterone synthase protein reduction. These could be reversed when exposed to ROS inhibitor or endoplasmic reticulum stress inhibitor. In conclusion, PS-MPs exposure induced the high level of ROS, activated the GRP78/p-PERK/CHOP signaling pathway, enhanced endoplasmic reticulum stress in leydig cells, then apoptosis level increased, which impaired the leydig cell function.
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PubMed
高影响因子
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