INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
·
2024
·
IF 7.7
Huanhuan Jin,Ziyuan Wang,Zhongji Pu,Haoran Yu,Yuhuan Chen,Xiaoshu Zhou,Lirong Yang,Shuyun Ju,Jianping Wu
Optically pure 1,2,3,4-tetrahydroquinolines (THQs) represent a class of important motifs in many natural products and pharmaceutical agents. While recent advances on redox biocatalysis have demonstrated the great potential of amine oxidases , all the transformations focused on 2-substituted THQs. The corresponding biocatalytic method for the preparation of chiral 4-substituted THQs is still challenging due to the poor activity and stereoselectivity of the available enzyme . Herein, we developed a biocatalytic kinetic resolution approach for enantiodivergent synthesis of 4-phenyl- or alkyl-substituted THQs. Through structure-guided protein engineering of cyclohexylamine oxidase derived from Brevibacterium oxidans IH-35 A (CHAO), the variant of CHAO (Y215H/Y214S) displayed improved specific activity toward model substrate 4-phenyl substituted THQ (0.14 U/mg, 13-fold higher than wild-type CHAO) with superior ( R )-stereoselectivity ( E > 200). Molecular dynamics simulations show that CHAO Y215H/Y214S allows a suitable substrate positioning in the expanded binding pocket to be facilely accessed, enabling enhanced activity and stereoselectivity . Furthermore, a series of 4-alkyl-substituted THQs can be transformed by CHAO Y215H/Y214S, affording R -isomers with good yields (up to 50 %) and excellent enantioselectivity (up to ee > 99 %). Interestingly, the monoamine oxidase from Pseudomonas fluorescens Pf0–1 ( Pf MAO1) with opposite enantioselectivity was also mined. Together, this system enriches the kinetic resolution methods for the synthesis of chiral THQs.
研究领域:
生物催化
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有机化学
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蛋白质工程
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药物科学
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DOI
PubMed
高影响因子
MACROMOLECULAR CHEMISTRY AND PHYSICS
·
2020
·Vol. 221
·期 9
·2000035
·
IF 2.335
Yu Wang,Alberto García-Peñas,Santiago Gómez-Ruiz,Florian J. Stadler
The functionalization of different structures with organometallic complexes provides exciting properties in terms of applicability due to its ability to provide multiple benefits for catalysis and biomedicine as well as in other fields. This work reports the direct, facile functionalization of copolymers based on N -isopropylacrylamide and dopamine methacrylamide with bis(cyclopentadienyl)titanium (IV) dichloride (Cp 2 TiCl 2 , Cp = η 5 -C 5 H 5 ), which can offer an easy preparation method in comparison with other functionalization procedures. In addition, the lower critical solution temperature (LCST) is studied through aqueous solutions of new structures, which is affected by the presence of the metallocene moieties. UV–vis spectroscopy shows an average of the LCST-behavior in comparison with rheology that provides essential information about the changes of the phase transition temperature associated with the composition of the polymeric chains and their interactions with the medium. Then, the inclusion of an organometallic complex along the polymeric chain can partially modify the phase transition temperature due to the interactions promoted by the organometallic complex of surroundings over the polymeric sections free of comonomer content.
研究领域:
高分子化学
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材料科学
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物理化学
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DOI
高影响因子
iScience
·
2022
·
IF 6.107
Kefeng Wang,Qingzhen Yu,Wenli Mao,Yuxin Zheng,Jing Xu,Yukun Wang
Vinylboron compounds are important compounds in organic chemistry and biology. In this communication, we developed a copper(I)-catalyzed, highly regio- and stereoselective radical trans -hydroboration of ynamides with N -heterocyclic carbene (NHC)-ligated borane is reported, which leads to a series of trans -boryl enmides that can be conveniently transformed into various multi-substituted enamides. Further investigation showcased that our method is robust and scalable. The mechanism of this unique reaction is studied and discussed.
研究领域:
有机化学
·
合成化学
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DOI
PubMed
高影响因子
Desalination and Water Treatment
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2024
·
IF 1
Chaojie Cai,Xiaobin Lei,Xinzhen Zhao,Lin Wang,Jizhen Jia,Changkun Liu
ABSTRACT Modification of the active layer is an effective method to improve the separation performance of the thin-film composite forward osmosis (FO) membranes. In this paper, the dendrimer polyamidoamine (PAMAM) was in-situ integrated into the polyamide (PA) active layer via the interfacial polymerization. The separation performance results showed that the addition of PAMAM significantly improved the separation water flux of the modified FO membrane by 1.7 times, and the reverse salt flux was almost unchanged. In addition, the removal efficiency of the modified FO membrane for heavy metal ions was enhanced, with the rejection rates of various heavy metal ions all higher than 99.6%, and the corresponding water flux was also significantly enhanced. The PAMAM integrated with the active layer contained a large number of hydrophilic segments and terminal amine groups, which in situ enhanced the hydrophilicity and permeability of the active layer, and further improved the removal of heavy metal ions based on the coordination and electrostatic repulsion effects. The purpose of this paper is to provide a feasible way to improve the practical application performance of the FO membranes.
研究领域:
环境工程
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材料科学
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水处理技术
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DOI
高影响因子
ChemPlusChem
·
2024
·
IF 3
Yong Wang,Xueying Lin,Xianyu Ying,Shan Hu,Hongjun Zhu
A facile C–H amination of quinazoline employing N-fluorobenzenesulfonimide (NFSI) as the amination source has been disclosed in the absence of any metal, oxidant or additive. The methodology shows a board range of quinazolines with different functional groups in moderate to good yields up to 87%. Furthermore, gram-scale reaction, desulfonylation to amine and synthesis of pharmaceutical intermediate were also investigated, which demonstrates potential applications in medicinal chemistry. A plausible amination mechanism is proposed via F+ transfer accompanied by the removal of one molecule of PhSO2F. DFT studies with experimental work suggest that the mechanism via F+ transfer is more favorable than the free radical one.
研究领域:
有机化学
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药物化学
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合成化学
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DOI
PubMed
高影响因子
JOURNAL OF CHROMATOGRAPHY A
·
2021
·
IF 4.759
Qingxiang Zhou,Yongyong Yuan,Yi Sun,Xueying Sheng,Yayan Tong
Present study described a sensitive and efficient method for determination of heterocyclic aromatic hydrocarbons using multiwalled carbon nanotubes modified magnetic polyamido-amine dendrimers (MNPs@PAMAM-Gn@MWCNTs) as adsorbent for magnetic solid-phase extraction (MSPE) coupled with gas chromatography-triple quadrupole mass spectrometer (GC–MS/MS). Some pivotal parameters including PAMAM generation, adsorbent dosage, adsorption time, elution time and volume, pH and humic acid concentration were investigated to achieve the best adsorption efficiencies. Under the optimal conditions, 7-methylquinoline, dibenzothiophene and carbazole had good linearity in the concentration range of 0.005–20 μg L − 1 , 9-methylcarbazole, 4-methyldibenzothiophene and 4,6-dimethyl dibenzothiophene had good linearity in the concentration range of 0.001–20 μg L − 1 . All the correlation coefficients were higher than 0.996. The detection limits of the targets were in the range of 2.2 × 10 −4 –1.8 × 10 −3 μg L − 1 with precisions less than 8.28% ( n = 6). The enrichment factors were in the range of 141–147. The spiked recoveries were in the range of 87.0%-115.1% ( n = 3). These results indicated that the method could be a reliable alternative tool for monitoring trace heterocyclic aromatic hydrocarbons in environmental water samples.
研究领域:
分析化学
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环境科学
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DOI
高影响因子
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
·
2016
·
IF 2.567
Li Hao,Bin Jiang,Luhong Zhang,Huawei Yang,Yongli Sun,Baoyu Wang,Na Yang
A series of amine-based dendrimer polyamidoamine (PAMAM) demulsifiers with different initial cores were synthesized and investigated in the demulsification process of diesel-in-water emulsions. With the aim of systemic evaluation of their demulsification performance, some important factors of the demulsification processes were investigated including demulsifier dosage, settling time, temperature, oil content, and kinds of diesel. The demulsifier with the triethylenetetramine (TETA) initial core provided excellent demulsification performance by removing oil with less dosage and at relatively low temperature in short periods and reached 96.66% demulsification efficiency for catalytic cracking diesel emulsion. The results showed its good application prospects. In order to gain insight into the demulsification process and mechanism, some measurement methods were adopted. Micrograph and droplet size distribution of emulsions illustrated that the PAMAM demulsifier could lead to the breakup of diesel-in-water emulsions by flocculation and coalescence. The surface tension and interfacial tension gave a basic understanding of the demulsification mechanism. Zeta potential indicated that emulsion had been broken up. The conductivity measurement explained the demulsification mechanism from the aspect of the electrostatic interactions of moving droplets. The dendrimer and SDS had strong aggregation interactions in the system according to the results of hydrodynamic radium.
研究领域:
环境化学
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胶体与界面科学
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高分子化学
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石油污染治理
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分离技术
✓ 已验证
DOI
高影响因子
Nanoscale
·
2012
·Vol. 4
·期 23
·7585-7592
·
IF 5.914
Xianfeng Wang,Jialin Wang,Yang Si,Bin Ding,Jianyong Yu,Gang Sun,Wenjing Luo,Gang Zheng
This work describes the detection of trace hydrogen chloride (HCl) gas through analyses of the resonance frequency signal from quartz crystal microbalance (QCM) sensors coated with polyaniline (PANI) functionalized polyamide 6 (PA 6) (PANI-PA 6) nanofiber-net-binary (NNB) structured membranes. The PA 6 NNB substrate comprising nanofibers and spider-web-like nano-nets fabricated by a versatile electro-spinning/netting (ESN) process offered an ideal interface for the uniform PANI functionalization and enhanced sensing performance. Benefiting from the large specific surface area, high porosity, and strong adhesive force to the QCM electrode of the PANI-PA 6 NNB membranes, the developed HCl-selective sensors exhibited a rapid response, good reproducibility and stability, and low detection limit (7 ppb) at room temperature. Additionally, the PANI-PA 6 NNB sensing membranes presented visible color changes upon cycled exposure to HCl and ammonia, suggesting their potential application in the development of colorimetric sensors. The PANI-PA 6 NNB coated QCM sensors are considered to be a promising candidate for trace HCl gas detection in practical applications.
研究领域:
分析化学
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传感器技术
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材料科学
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环境监测
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气体传感
✓ 已验证
DOI
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2022
·Vol. 139
·期 24
·52348
·
IF 3.057
Yang Ma,Yanjun Hou,Yuhang Zhang,Lijing Chang,Rui Li,Haijun Niu
Based on the performance of improving the stabilities and coloring efficiencies of triphenylamine polymers, this paper separately synthesized different diamines and 3,4-dimethylthieno[2,3-b]thiophene-2,5-dicarboxylic acid, and the electrochromic functions of the polymer films were studied on indium-tin oxide glass (ITO) glass. The polymers had a thiophene group, which was rich in π-electrons and conducive to molecular stability, and showed good stabilities. Ultraviolet spectrum showed that all the six polymers had a wide absorption band in the neutral range of 200–700 nm. Electrochromic analysis showed that the six kinds of polymer films all showed reasonable optical contrast, short response time and low band gap in the infrared spectrum range of 200–1000 nm. Among them, the film formed by PAD2 on ITO glass had better electrochromic properties, longer bleaching response time ( t c = 1.3 s, t b = 4.1 s), PAD3 had better coloration efficiency (214 cm 2 C −1 ).
研究领域:
材料科学
·
电化学
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DOI
高影响因子
ACS Omega
·
2020
·
IF 2.87
Panpan Zhang,Ke Zhang,Xi Chen,Shuliang Dou,Jiupeng Zhao,Yao Li
In this work, the effect of coagulation bath temperature in different solvent systems [1,4-butyrolactone (GBL)/N,N-dimethylacetamide (DMAC)] on the structure and dielectric properties of polyimide (PI) films was investigated for the first time. The solubility parameter was introduced to explain the formation process of porous PI films. The results showed that the changed tendency of the dielectric constant versus temperature is opposite for the single-solvent system and cosolvent system. For a single DMAC and GBL solvent, the dielectric constants of the films decreased with increasing temperature. In contrast, the dielectric constants increased with the increase in temperature for the GBL/DMAC cosolvent system. Moreover, the measured porosities were applied to estimate the dielectric constants of the PI films. This showed that the porosity increased with increasing temperature for a single-solvent system, while it decreased for a cosolvent system. Scanning electron microscopy images suggested that the variation trends are derived from the different influences of the temperature on the structure and morphology. Thus, this study reveals the effect of coagulation bath temperature on the structure and dielectric properties of porous PI films and provides the guidance for the design and optimization of architectures for high-performance porous films.
研究领域:
材料科学
·
高分子化学
·
电气工程
✓ 已验证
DOI
PubMed
高影响因子
ChemistrySelect
·
2023
·Vol. 8
·期 34
·e202302554
·
IF 2.1
Lijun Zhang,Yu Li,Haitao Zhao,Xiang Xu,Jiannan Cheng,Weiwei He,Lifen Zhang,Zhenping Cheng
Graphical Nonflammable and broad-spectrum adsorbent MS@PDA@PA with high thermal stability based on melamine sponge (MS) is prepared conveniently employing the phytic acid (PA) and polydopamine (PDA) as the modifier and linking agent respectively through a green process. Radioactive uranyl and transition heavy metal ions including Pb(II), Cu(II), Cr(III) can be effectively adsorbed by the material. Adsorption is an effective technology widely used in the removal of radioactive and other heavy metal ions, the adsorbent plays critical role and development of novel adsorbents is being in urgent demand. In this work, phytic acid (PA)-modified melamine sponge (MS) adsorbent MS@PDA@PA is prepared conveniently in green solvent water. A wide spectrum of metal ions including radioactive uranyl and transition heavy metal ions can be effectively adsorbed by the MS@PDA@PA due to non-selectivity of phosphoric acid groups in PA. Different factors including pH of aqueous solution, contact time, and initial concentration of ions on the effect of adsorption of the resultant materials are investigated in detail, and the maximum adsorption capacities for U(VI), Pb(II), Cu(II), Cr(III) are 166.7, 168.5, 114.3, and 101.0 mg g −1 respectively at 298 K. It is notable that the MS@PDA@PA is nonflammable due to employment of MS as frame material, and the thermal stability is even improved after incorporation of PA, greatly reduce the risk of the adsorbent in the processes of storage and usage. The green yet simple synthesis and fire resistance of MS@PDA@PA make it a competitive material for practical treatment of wastewater consisting of toxic metal ions.
研究领域:
环境科学
·
材料科学
·
化学
✓ 已验证
DOI
高影响因子
MOLECULES
·
2022
·Vol. 27
·期 5
·1537
·
IF 4.927
Juan Ma,Guo-Hua Gong
In this paper, a small series of novel quinoline sulfonamide derivatives was synthesized, and their structure of the target compounds were confirmed by 1H NMR and MS. The screening of the news target compounds’ in vitro cytotoxic activities against tumor cell lines by the MTT method was performed. Among them, compoundD13(N-(4-methoxybenzyl)-2-oxo-N-(3,4,5-trimethoxyphenyl)-1,2,3,4-tetrahydroquinoline-6-sulfonamide exhibited the strongest inhibitory effect on the proliferation of HeLa (IC50: 1.34 μM), and this value correlated well with the inhibitory activities of the compound against tubulin polymerization (IC50: 6.74 μM). In summary, a new type of quinoline-sulfonamide derivative with tubulin polymerization inhibitory activity was discovered, and it can be used as a lead compound for further modification.Keywords:synthesis;quinoline-sulfonamide;anti-tumor;tubulin polymerization
研究领域:
药物化学
·
肿瘤学
✓ 已验证
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）