CATALYSIS COMMUNICATIONS
·
2019
·
IF 3.674
Yuanmei Wen,Liaotian Peng,Yang Zhou,Tao Peng,Yu Chen,Xiaoling Cheng,Yongzheng Chen,Jiawei Yang
Here we report a methionine sulfoxide reductase B (MsrB) enzymatic system for the preparation of ( S )-sulfoxides through kinetic resolution of racemic ( rac ) sulfoxides. Eight MsrB homologue recombinant proteins were expressed and their activities on asymmetric reduction of rac -sulfoxides were analyzed. Among these MsrB homologue proteins, one protein from Acidovorax species showed good activity and enantioselectivity towards several aryl-alkyl sulfoxides. The ( S )-sulfoxides were prepared with 93–98% enantiomeric excess through kinetic resolution at initial substrate concentration up to 50 mM. The establishment of MsrB catalytic kinetic resolution system provides a new efficient green strategy for preparation of ( S )-sulfoxides.
研究领域:
生物化学
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合成生物学
·
绿色化学
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DOI
高影响因子
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
·
2024
·
IF 7.7
Quan Zhang,Bochen Pan,Piao Yang,Jin Tian,Shihuan Zhou,Xianlin Xu,Yangxue Dai,Xiaoling Cheng,Yongzheng Chen,Jiawei Yang
Methionine sulfoxide reductase A (MsrA) has emerged as promising biocatalysts in the enantioselective kinetic resolution of racemic ( rac ) sulfoxides . In this study, we engineered robust MsrA variants through directed evolution, demonstrating substantial improvements of thermostability . Mechanism analysis reveals that the enhanced thermostability results from the strengthening of intracellular interactions and increase in molecular compactness. Moreover, these variants demonstrated concurrent improvements in catalytic activities, and notably, these enhancements in stability and activity collectively contributed to a significant improvement in enzyme substrate tolerance. We achieved kinetic resolution on a series of rac -sulfoxides with high enantioselectivity under initial substrate concentrations reaching up to 93.0 g/L, representing a great improvement in the aspect of the substrate concentration for biocatalytic preparation of chiral sulfoxide. Hence, the simultaneously improved thermostability, activity and substrate tolerance of MsrA represent an excellent biocatalyst for the green synthesis of optically pure sulfoxides.
研究领域:
生物化学
·
酶工程
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合成生物学
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DOI
PubMed
高影响因子
GREEN CHEMISTRY
·
2011
·Vol. 14
·期 1
·130-135
·
IF 5.472
Bin Li,An-Hua Liu,Liang-Nian He,Zhen-Zhen Yang,Jian Gao,Kai-Hong Chen
Readily available iron compounds were found to be active catalysts for the selective oxidation of sulfide to sulfoxide with molecular oxygen as the oxidant in polyethylene glycol (PEG). As an indispensable component, PEG had a great promotive effect on the reaction. Notably, high conversion (>99%) along with excellent chemo-selectivity of up to 94% could be attained by using Fe(acac)2 as the catalyst at 100 °C. This methodology was proved to be applicable for the transformation of various aromatic and aliphatic sulfides into the corresponding sulfoxides with high selectivity. PEG is considered to play a crucial role in stablizing the Fe(IV)-oxo species formed in situ which is supposed to be responsible for the sulfide oxidation.
研究领域:
有机化学
·
催化化学
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DOI
高影响因子
LANGMUIR
·
2019
·
IF 3.683
Yanxia Wei,Linli Hu,Jinrong Yao,Zhengzhong Shao,Xin Chen
The conformation and stability of zein in solution are closely associated with its solvation process and influence the mechanical properties of the related zein-based materials. In this work, a common solvent dimethyl sulfoxide (DMSO) was used to dissolve zein, rather than solvents frequently used such as aqueous ethanol and acetic acid. It was found that DMSO could dissolve zein readily and the solution was stable for at least 2 weeks. Rheological analysis and small-angle X-ray scattering (SAXS) were employed to characterize the zein DMSO solution. Results of rheological analysis suggested a Huggins coefficient of 0.24, indicating DMSO to be a good solvent for zein. SAXS results revealed that zein adopted an elongated conformation and had dimensions of 2.8 nm × 2.8 nm × 14.8 nm in DMSO solution. Moreover, robust zein films were fabricated from zein DMSO solutions. The content of residual DMSO in the films was determined to be approximately 15 wt % by thermogravimetric analysis, in consistence with the value obtained by other two methods. The film showed a large breaking strain of 320.6% with a considerable breaking stress of 1.9 MPa, yielding a breaking energy of 376.2 MJ/m3. Therefore, the ease of dissolution and good mechanical performance of the final zein-based material make DMSO a potential solvent for fabrication of zein materials, thereby improving the scope of practical applications of zein.
研究领域:
材料科学
·
生物化学
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产品关联
DOI
PubMed
高影响因子
CHINESE JOURNAL OF CATALYSIS
·
2014
·
IF 1.552
Wenju Wang,Huiling Li,Junli Ren,Runcang Sun,Jie Zheng,Guangwei Sun,Shijie Liu
An efficient homogeneous catalytic process was developed for the dehydration of xylose to furfural using inorganic salts as catalysts in a water/dimethyl sulfoxide (DMSO) system under mild condition. The effects of the types of inorganic salts were compared. The results showed that chlorides had higher catalytic performance than other salts, and SnCl 4 was the most effective chloride. The catalytic activity of paired SnCl 4 /LiCl catalysts was much higher than that of the single salt, and when the distribution coefficient ( χ SnCl4 ) was 0.8, the maximum furfural yield was 56.9%. The effects of the reaction conditions on the furfural yield were also investigated. The highest furfural yield, 63.0%, was achieved at 130 °C for 6 h under the optimized reaction conditions.
研究领域:
化学工程
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生物化工
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产品关联
DOI
高影响因子
MOLECULES
·
2015
·Vol. 20
·期 9
·16709-16722
·
IF 2.416
Hai-Min Shen,Wen-Jie Zhou,Xin Ma,Hong-Ke Wu,Wu-Bin Yu,Ning Ai,Hong-Bing Ji,Hong-Xin Shi,Yuan-Bin She
A pH-dependence of the Brønsted acid-catalyzed oxidation of sulfides to the corresponding sulfoxides with H2O2is reported for the first time based on our systematic investigation of the catalytic performance of a series of Brønsted acids. For all of the Brønsted acids investigated, the catalytic performances do not depend on the catalyst loading (mol ratio of Brønsted acid to substrate), but rather depend on the pH value of the aqueous reaction solution. All of them can give more than 98% conversion and selectivity in their aqueous solution at pH 1.30, no matter how much the catalyst loading is and what the Brønsted acid is. This pH-dependence principle is a very novel perspective to understand the Brønsted-acid catalysis system compared with our common understanding of the subject.Keywords:sulfide;oxidation;sulfoxide;pH-dependence;Brønsted acid
研究领域:
化学
·
催化科学
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DOI
PubMed
高影响因子
MATERIALS SCIENCE FORUM
·
2020
·
IF 0
Zheng Li,Zi Jian He,Ying Cheng Zhou,Yi Tang,Yu Fang Chen,Tao Jin
In this paper, Dimethyl sulfoxide (DMSO) was used in the activating process of cotton filter cloth to improve its further hydrophobic modification reaction between cotton fabric and 1-octadecene via an electron transfer (ARGET) atom transfer radical polymerization (ATRP) mechanism. The major influences of DMSO on ARGET-ATRP process was discussed, and meanwhile, the microstructure changes, morphology feature and performance characteristics of cotton filter cloth during the reaction was explored by the SEM, AFM, EDS, XRD and TGA techniques.The result shows that DMSO can leads to cotton fibers adhesion and surface roughening under the ARGET-ATRP grafting reaction conditions, but has little changes on the crystal form, crystallinity and thermal properties of cellulose. At a DMSO dosage of 10%, the hydrophobically modified cotton filter cloth has a water contact angle (CA) of up to 141°. While naturally placed for 1 hour, the CA of hydrophobically modified cotton filter cloth can be stable at 116° with a decay rate of 17.5%, which proves that the hydrophobic stability of cotton filter cloth has been improved markedly. Furthermore, a better improvement for the hydrophobic stability of cotton filter cloth will significantly enhance the application of hydrophobic functional modified cellulosic materials.
研究领域:
材料科学
·
纺织工程
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DOI
DENTOMAXILLOFACIAL RADIOLOGY
·
2021
·Vol. 50
·期 7
·
IF 2.419
Hu ZiYang,Wang TieMei,Pan Xiao,Cao DanTong,Liang JiaHao,Gao AnTian,Xie Xin,Xu Shi,Miao LeiYing,Lin ZiTong
Objectives:To evaluate the diagnostic accuracy using sodium iodide (NaI) and dimethyl sulfoxide (DMSO) as contrast agent in cone beam computed tomography (CBCT) scanning, and compare this with micro-CT.Methods:18 teeth were cracked artificially by soaking them cyclically in liquid nitrogen and hot water. After pre-treatment with artificial saliva, the teeth were scanned in four modes: CBCT routine scanning without contrast agent (RS); CBCT with meglumine diatrizoate (MD) as contrast agent (ES1); CBCT with NaI + DMSO as contrast agent (ES2); and micro-CT (mCT). The number of crack lines was evaluated in all four modes. Depth of crack lines and number of cracks presented from the occlusal surface to the pulp cavity (Np) in ES2 and micro-CT images were evaluated.Results:There were 63 crack lines in all 18 teeth. 45 crack lines were visible on ES2 images as against four on the RS and ES1 images (p<0.05) and 37 on micro-CT images (p>0.05). Further, 34 crack lines could be observed on both ES2 and micro-CT images, and the average depth presented on ES2 images was 4.56 ± 0.88 mm and 3.89 ± 1.08 mm on micro-CT images (p<0.05). More crack lines could be detected from the occlusal surface to the pulp cavity on ES2 images than on micro-CT images (22 vs 11).Conclusion:CBCT with NaI +DMSO as the contrast agent was equivalent to micro-CT for number of crack lines and better for depth of crack lines. NaI + DMSO could be a potential CBCT contrast agent to improve diagnostic accuracy for cracked tooth.
研究领域:
口腔医学
·
影像学
✓ 已验证
DOI
高影响因子
JOURNAL OF ORGANIC CHEMISTRY
·
2022
·
IF 4.198
Jiateng Wang,Yunqing Zhuang,Bingxue Yu,Xiaofeng Wang,Gehua Bi,Xin Huang,Weimin Zhang
A general and efficient method for the synthesis of 4-sulfenylated oxazoles is described. Trisubstituted oxazoles are obtained in good to excellent yields from β-keto sulfoxides and nitriles. The mechanistic study suggests that the reaction proceeds via the nucleophilic addition of nitriles to the in situ formed α-carbonyl cation followed by intramolecular cyclization.
研究领域:
有机化学
·
药物化学
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DOI
高影响因子
JOURNAL OF CHEMICAL THERMODYNAMICS
·
2020
·
IF 2.888
Midong Shi,Wei Zeng,Shixian Song,Meiting Zhou,Wei Wang
Liquid-liquid equilibrium (LLE) data for {n-heptane + p-xylene (PX) + furfural/dimethyl sulfoxide (DMSO)} ternary systems were measured at 303.15 K and 323.15 K and atmospheric pressure. Extraction performance of furfural and DMSO were evaluated using distribution coefficient (D) and selectivity (S) according to the measured tie-line data. And the results showed that DMSO had better extraction performance than furfural for separation of n-heptane and PX. Both UNIQUAC and NRTL models were used to correlate the experimental LLE data, and relevant interaction parameters were obtained. Consistency between the measured LLE data and the calculated by these two models was well evaluated by RMSD and maximum absolute deviation. Moreover, reliability of binary interaction parameters was confirmed by topological analysis related to the Gibbs tangent plane test.
研究领域:
化学工程
·
物理化学
✓ 已验证
产品关联
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2019
·
IF 5.107
Yuhao Zhang,Hui Wang,Liang Zhao,Jinsen Gao,Chunming Xu
The performance of dimethyl sulfoxide (DMSO) solvent in separating olefins from aromatics and thiophene sulfides was evaluated through a series of ternary liquid-liquid equilibrium (LLE) experiments at 101.325 kPa and 303.15 K. The influences of the structures of olefins, aromatics, and thiophene sulfides on the separation efficiency were analyzed. Normal 1-hexene and isomer 2,4,4-trimethyl-1-pentene were easily separated from aromatics or thiophene sulfides, which only contain aromatic ring structures, such as benzene and thiophene. The reason is that the induced dipole on the aromatic ring structure introduced by the DMSO solvent significantly improved the polarity of aromatics and thiophene sulfide molecules, thereby enhancing the interaction with the ring structure. In addition, olefins were easier to separate from thiophene sulfides than from aromatics. The olefin separation factor of separating 2,4,4-trimethyl-1-pentene from thiophene was three times greater than that of separating the same olefin from benzene. The binary parameters between DMSO and olefins, aromatics, and thiophene sulfides for NRTL and UNIQUAC models were obtained through ternary LLE experiments. The maximum value of the root-mean-square deviation of the simulated compositions of phases compared with experimental data was 0.0052 in the two adopted models. Hence, the regressed binary parameters could efficiently describe the experimental LLE process. On the basis of the obtained binary parameters, the NRTL and UNIQUAC models are suitable for predicting the performance of olefin separation from fluid catalytic cracking naphtha. However, the NRTL model is more precise than the UNIQUAC model.
研究领域:
化学工程
·
热力学
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产品关联
DOI
高影响因子
RSC Advances
·
2015
·Vol. 5
·期 81
·66376-66383
·
IF 3.84
Yixian Huang,Yu Tong,Chen Wang,Ke Tang,Yanzhao Yang
A group of new asymmetric branched alkyl sulfoxides was synthesized and applied in palladium(II) extraction for the first time. According to the experimental data, the concentration of hydrochloric acid in aqueous phase greatly influenced Pd(II) extraction, which could be interpreted by different mechanisms (ligand substitution mechanism at low acidity and ion association mechanism at high acidity). In regard to structure effect, the steric hindrance of branched alkyl showed remarkable influence on the extraction performance of sulfoxides. On the basis of thermodynamic analysis, it was demonstrated that higher temperature exerted positive influence on the Pd(II) extraction reaction. As for the separation of Pd(II) and Pt(IV), low concentration of hydrochloric acid was considered to be appropriate for highly effective separation. Furthermore, ammonia solution was proven to be an efficient stripping agent for palladium recovery from organic phase.
研究领域:
化学
·
材料科学
✓ 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）