JOURNAL OF ORGANIC CHEMISTRY
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2020
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IF 4.335
Nian Zheng,Ce Liu,Ya-Nan Ding,Wei-Yu Shi,Bo-Sheng Zhang,Yong-Min Liang
Copper-catalyzed three-component redox-neutral ring opening of benzothiazoles with aryl iodides and O-benzoyl hydroxylamines for the synthesis of 1-amino-N-(2-(phenylthio)phenyl)methanimine has been developed. This one-pot reaction undergoes C–S and N–O bond cleavage and new C–S and C–N bond construction. Several control experiments excluded a free radical procedure and also demonstrated the secondary amine as a possible intermediate, which was vital to the catalytic reaction. Meanwhile, the deuteration experiment got rid of the C–H activation dehydroisomerization of the benzothiazole mechanism.
研究领域:
有机化学
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合成化学
✓ 已验证
DOI
PubMed
高影响因子
ACS Applied Polymer Materials
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2025
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IF 4.7
Xiangzhuo Han,Yingchao Zhang,Jinkai Wang,Zhanchen Cui,Zuosen Shi
Sulfonate oxime ester photoinitiators (PIs) based on a thioether-substituted 1,8-naphthalenedicarboximide backbone exhibit good absorption at the emission wavelengths of commonly used LED lamps (385, 395, and 405 nm). The presence of weak C–S and N–O bonds in the molecular structure enables them to be cleaved under light, which leads to the generation of free radicals and cations with efficient initiation properties. Electron paramagnetic resonance spectroscopy supports the mechanism of C–S bond cleavage to produce free radicals, and UV–visible real-time spectroscopy in the presence of Rhodamine B base supports the mechanism of N–O bond cleavage to produce acids. These compounds are high-performance photoinitiators without any other additives for the polymerization of double-bonded compounds and epoxides. They can be initiated at low concentrations when exposed to UV-LEDs. These photoinitiators provide important ideas for the design and synthesis of photoinitiators, which have great potential for application in the field of photopolymerization, especially in hybrid light-curing systems.
研究领域:
材料科学
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光化学
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聚合物科学
✓ 已验证
产品关联
DOI
高影响因子
APPLIED AND ENVIRONMENTAL MICROBIOLOGY
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2017
·Vol. 83
·期 23
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IF 3.807
Cui-Wei Chu,Bin Liu,Na Li,Shi-Gang Yao,Dan Cheng,Jia-Dong Zhao,Ji-Guo Qiu,Xin Yan,Qin He,Jian He
Thiobencarb is a thiocarbamate herbicide used in rice paddies worldwide. Microbial degradation plays a crucial role in the dissipation of thiobencarb in the environment. However, the physiological and genetic mechanisms underlying thiobencarb degradation remain unknown. In this study, a novel thiobencarb degradation pathway was proposed in Acidovorax sp. strain T1. Thiobencarb was oxidized and cleaved at the C—S bond, generating diethylcarbamothioic S-acid and 4-chlorobenzaldehyde (4CDA). 4CDA was then oxidized to 4-chlorobenzoic acid (4CBA) and hydrolytically dechlorinated to 4-hydroxybenzoic acid (4HBA). The identification of catabolic genes suggested further hydroxylation to protocatechuic acid (PCA) and finally degradation through the protocatechuate 4,5-dioxygenase pathway. A novel two-component monooxygenase system identified in the strain, TmoAB, was responsible for the initial catabolic reaction. TmoA shared 28 to 32% identity with the oxygenase components of pyrimidine monooxygenase from Agrobacterium fabrum, alkanesulfonate monooxygenase from Pseudomonas savastanoi, and dibenzothiophene monooxygenase from Rhodococcus sp. TmoB shared 25 to 37% identity with reported flavin reductases and oxidized NADH but not NADPH. TmoAB is a flavin mononucleotide (FMN)-dependent monooxygenase and catalyzed the C—S bond cleavage of thiobencarb. Introduction of tmoAB into cells of the thiobencarb degradation-deficient mutant T1m restored its ability to degrade and utilize thiobencarb. A dehydrogenase gene, tmoC, was located 7,129 bp downstream of tmoAB, and its transcription was clearly induced by thiobencarb. The purified TmoC catalyzed the dehydrogenation of 4CDA to 4CBA using NAD+ as a cofactor. A gene cluster responsible for the complete 4CBA metabolic pathway was also cloned, and its involvement in thiobencarb degradation was preliminarily verified by transcriptional analysis.IMPORTANCE Microbial degradation is the main factor in thiobencarb dissipation in soil. In previous studies, thiobencarb was degraded initially via N-deethylation, sulfoxidation, hydroxylation, and dechlorination. However, enzymes and genes involved in the microbial degradation of thiobencarb have not been studied. This study revealed a new thiobencarb degradation pathway in Acidovorax sp. strain T1 and identified a novel two-component FMN-dependent monooxygenase system, TmoAB. Under TmoAB-mediated catalysis, thiobencarb was cleaved at the C—S bond, producing diethylcarbamothioic S-acid and 4CDA. Furthermore, the downstream degradation pathway of thiobencarb was proposed. Our study provides the physiological, biochemical, and genetic foundation of thiobencarb degradation in this microorganism.
研究领域:
环境微生物学
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分子生物学
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生物化学
✓ 已验证
DOI
高影响因子
JOURNAL OF ANALYTICAL AND APPLIED PYROLYSIS
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2024
·
IF 5.8
Mingshuo Chi,Jianpeng Cui,Jianwen Hu,Junjie Fan,Senchang Du,Peiwen Xiao,Songqing Hu,Shuangqing Sun
The enhancement of heavy oil recovery and the promotion of oil-water separation are crucial aspects of fossil fuel resource development. In this study, silica Janus nanosheets were prepared and anchored with Ni nanoparticles for in-situ upgrading and stimulus-responsive demulsification of heavy oil. The results of aquathermolysis reactions revealed that Ni/Ph-SiO 2 -Ni/P4VP Janus nanosheets exhibited excellent characteristics in reducing heavy oil viscosity by 98.49 %, and 99.52 % with the addition of a hydrogen donor. FT-IR, 1 H NMR and GC, etc. analysis of the oil samples indicated that Ni/Ph-SiO 2 -Ni/P4VP breaks the C-S bond and reduces the content of the resin, asphaltene , polycyclic aromatics, and long chain alkanes in the oil. Moreover, it can stabilize heavy oil emulsions in an acidic medium (pH = 2) and separate oil and water in a neutral medium (pH = 7) due to its stimulus-responsive performance. This work highlights the potential application of Ni/Ph-SiO 2 -Ni/P4VP Janus nanosheets for the in situ upgrading and stimulus-responsive demulsification of heavy oil.
研究领域:
材料科学
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化学工程
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石油工程
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纳米技术
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环境科学
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）