Catalysis Science & Technology
·
2022
·Vol. 12
·期 23
·7208-7218
·
IF 6.177
Wenjing Song,Yujie Wan,Yuefeng Li,Xin Luo,Weiping Fang,Quanxing Zheng,Pengfei Ma,Jianping Zhang,Weikun Lai
Low cost and high efficiency catalysts for the reductive amination of carbonyl compounds are critical to the utilization of renewable biomass. In this paper, a highly efficient N-doped porous carbon supported Ni catalyst was prepared by a template-assisted pyrolysis and impregnation method. In the presence of NH3 and H2, the as-prepared catalyst could effectively catalyze the reductive amination of various carbonyl compounds into corresponding primary amines with high yield and excellent stability. Comprehensive characterization demonstrated that the reductive amination of furfural towards furfuryl amine was linked to the formation of Ni–Nx sites and the electronic interaction of N and Ni species on the N-doped carbon surface, which promoted the reductive amination of CO bonds and significantly reduced the activation energy in reductive ammonolysis of trimers and Schiff base intermediates. This work provided a new insight into rational design of reductive amination catalysts for primary amine production.
研究领域:
催化化学
·
可再生资源利用
✓ 已验证
DOI
高影响因子
Catalysts
·
2022
·Vol. 12
·期 10
·1278
·
IF 4.501
Ying Wang,Huilin Xie,Kunming Liu,Jinhui Li,Jin-Biao Liu
Herein, we report a copper-catalyzed C-O cross-coupling of N-methoxy amides and arylboronic acids for the synthesis of aryl-N-methoxy arylimides. The fully selective O-arylation of the N-methoxy amides is found to be greatly prompted by the inexpensive and commercially available CuI. The reaction conditions tolerate a variety of functional groups and promote different reactivities depending on the electronic and steric properties of the distorted substrates.Keywords:copper catalyzed;N-methoxy amides;selective C-O cross-coupling;aryl-N-methoxy arylimides
研究领域:
有机化学
·
合成化学
✓ 已验证
DOI
高影响因子
JOURNAL OF BIOACTIVE AND COMPATIBLE POLYMERS
·
2013
·
IF 2.207
Feng Xu,Ting-Ting Yan,Yan-Ling Luo
Novel amphiphilic block copolymers consisting of hydrophobic poly(D,L-lactide) segments and hydrophilic poly(N-isopropylacrylamide-co-N, N-dimethylacrylamide) blocks were designed and synthesized through a simple free radical copolymerization route based on a bifunctional initiator, followed by the ring-opening polymerization of D,L-lactide. The copolymers self-assembled into thermosensitive spherical-nanosized core–shell micelles in aqueous solution in the presence or the absence of the model drug prednisone. The chemical and physical characterizations of drug-loaded and unloaded micelles revealed a lower critical solution temperature of 40°C–47°C, and a critical micelle concentration less than 7.20 mg L−1, a transmission electron microscope mean particle size from 50 to 75 nm, and a narrow dynamic light scattering diameter below 180 nm. The prepared blank and drug-loaded micellar nanoparticles were thermodynamically stabile and employed in targeted drug delivery by responding to the higher temperature of the local microenvironment. Based on prednisone release kinetic studies, structural changes of the self-assembled micelles as well as temperature- or environment-induced diffusion controlled drug release and improved bioavailability. The copolymer micelles exhibited good biocompatibility as established by the MTT cytotoxicity assay. Therefore, an effective target therapy against lesion tissues is feasible using these polymeric micelles.
研究领域:
材料科学
·
生物医学工程
·
药学
✓ 已验证
DOI
高影响因子
PLANT PHYSIOLOGY AND BIOCHEMISTRY
·
2018
·
IF 2.718
Chen Geng,Tengfei Zhao,Chunxian Yang,Qiaozhuo Zhang,Feng Bai,Junlan Zeng,Fangyuan Zhang,Xiaoqiang Liu,Xiaozhong Lan,Min Chen,Zhihua Liao
N -methylputrescine is the precursor of nicotine and pharmaceutical tropane alkaloids such as hyoscyamine . Putrescine N -methyltransferase (PMT) catalyzes the N -methylation of putrescine to form N -methylputrescine. While the role of PMT in nicotine biosynthesis is clear, knowledge of PMT in the biosynthesis of tropane alkaloids (TAs) and the regulation of polyamines remains limited. We characterized a PMT gene from Hyoscyamus niger , designated HnPMT that was specifically expressed in roots, especially in the secondary roots and dramatically induced by methyl jasmonate (MeJA). The GUS gene was specifically expressed in Arabidopsis roots or in the vascular tissues , including pericycles and endodermis , of the H. niger hairy root cultures , when it was driven by the 5′-flanking promoter region of HnPMT . The recombinant HnPMT was purified for enzymatic assays. HnPMT converted putrescine to form N -methylputrescine, as confirmed by LC-MS. The kinetics analysis revealed that HnPMT had high affinity with putrescine but low catalytic activity, suggesting that it was a rate-limiting enzyme . When HnPMT was suppressed in the H. niger plants by using the VIGS approach, the contents of N -methylputrescine and hyoscyamine were markedly decreased, but the contents of putrescine, spermidine and a mixture of spermine and thermospermine were significantly increased; this suggested that HnPMT was involved in the biosynthesis of tropane alkaloids and played a competent role in regulating the biosynthesis of polyamines . Functional identification of HnPMT facilitated the understanding of TA biosynthesis and thus implied that the HnPMT-catalyzed step might be a target for metabolic engineering of the TA production in H. niger .
研究领域:
植物学
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代谢工程
·
分子生物学
✓ 已验证
DOI
高影响因子
TETRAHEDRON
·
2024
·
IF 2.1
Nan Wang,Yuanyuan Huang,Mengke Wang,Weichun Huang,You Zi
Herein, a new approach for the synthesis of ( Z )- N -alkenyl-2-pyridones from 2-pyridones and propiolates using phosphine catalysis under mild conditions is reported. This dual Z -diastereoselective and N -selective reaction demonstrates excellent selectivity, yielding sole ( Z )- N -alkenyl-2-pyridones. Furthermore, scale-up studies confirm its practical applicability, with consistent efficiencies observed.
研究领域:
有机化学
·
合成化学
✓ 已验证
DOI
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2024
·
IF 9.4
Shuaishuai Li,Xudun Shen,Bowang Zhao,Longnian Tang,Yechen Qian,Wenyao Li,Shijie Li
Aqueous sodium-ion batteries (ASIBs) are promising for large-scale electrical energy storage (LSEES) applications due to their cost and safety advantages. However, the low voltage stabilization window of water (∼1.23 V) and the lack of cathode with high specific capacity and long cycle life have limited their development. Cobalt-based Prussian blue analogues (NaCoPBAs) have the advantage of high theoretical specific capacity but short cycle life. Recently, the molecular crowding electrolyte (MCE) strategy has been proposed to improve the electrolyte voltage stability window (ESW) of electrolytes, in this work, we report an improved xMC (x: ratio, MC: molecular crowding agent) electrolyte that uses N–N dimethylacetamide (DMAC) as the molecular crowding agent and NaOTf as the advanced salt with an ESW of 2.65 V and excellent nonflammability. The side reactions of the NaCoPBA//Hard Carbon (HC) full-cell active material are improved with the aid of the electrolyte. Capacity retention of 75 % after 600 cycles with excellent cycling stability. These results demonstrate that this advanced MCE strategy can be utilized for practical applications designed for safety, high specific capacity and long cycle (ASIB).
研究领域:
储能技术
·
电化学
·
材料科学
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电池技术
·
化学工程
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING SCIENCE
·
2024
·
IF 4.1
Yan Runhan,Cui Hongmin,Shi Jinsong,Yan Nanfu,Weng Yaqing,Cheng Ting,Wang Wei
There are still challenges in the recovery of rare earth elements (REEs) from leaching liquor of ion-adsorption type rare earth ore. In this paper, unsaponified N, N-di(2-ethylhexyl)-diglycolamic acid (HDEHDGA) was used to develop a green extraction process for efficient separation and enrichment of REEs. The cation exchange mechanism of RE(III) extraction was proposed by slope analysis and FT-IR spectra. HDEHDGA exhibited excellent extraction performances, such as short equilibrium time, high selectivity towards RE(III) and easy stripping by 0.5 mol/L HCl solution. REEs was enriched from 287.5 mg/L to 63.30 g/L by five-stage counter-current extraction and three-stage counter-current stripping using unsaponified HDEHDGA. The enrichment factor reached 220, and the proportion of REEs was increased from 80.76 wt% to 98.82 %. The loss of REEs was controlled below 2.14 wt%. This extraction strategy helps to improve the REEs recovery and avoid ammonia–nitrogen wastewater, which demonstrates its application potential in the ion-adsorption type rare earth ore.
研究领域:
化学工程
·
冶金工程
·
环境科学
✓ 已验证
DOI
高影响因子
GLYCOCONJUGATE JOURNAL
·
2018
·Vol. 35
·期 4
·411-420
·
IF 2.548
Wang Chengjian,Yang Meifang,Gao Xi,Li Cheng,Zou Zihua,Han Jianli,Huang Linjuan,Wang Zhongfu
Despite the great significance of release and analysis of glycans from glycoproteins, the existing N -glycan release methods are undermined by some limitations and deficiencies. The traditional enzymatic protocols feature high N -glycan release specificity but are generally costly and inefficient for some types of N -glycans. The existing chemical methods require harsh reaction conditions or are accompanied by the remarkable formation of by-products. Herein, we describe a versatile chemical method for the release and analysis of N -glycans from glycoproteins. This method differs from the existing methods as only aqueous ammonia is used to catalyze the N -glycan release reactions. Optimization of reaction conditions was performed using RNase B as a model glycoprotein and the obtained results indicated a highest N -glycan yield in ammonia at 60 °C for 16 h. Comparison of this method with traditional enzymatic protocols and recently reported NaClO methods confirmed the good reliability and efficiency of the novel approach. We also successfully applied this method to some complex biological samples, such as Ginkgo seed protein, fetal bovine serum (FBS) and hen egg white, and demonstrated its great compatibility with various neutral N -glycans, core α-1,3-fucosylated N -glycans and sialylated N -glycans. This method is very simple and cost-effective, enabling convenient analysis and large-scale preparation of released reducing N- glycans from various biological samples for structural and functional glycomics studies.
研究领域:
生物化学
·
分子生物学
·
分析化学
✓ 已验证
DOI
PubMed
高影响因子
JOURNAL OF CHEMICAL THERMODYNAMICS
·
2022
·
IF 3.269
Pan Zhang,Yanxi Ji,Wenya Li,Lihua Xu,Lemeng Wang,Dong Fu
The viscosities of N -(2-aminoethyl)ethanolamine (AEEA), 1,4-butanediamine (BDA) and N-methyl- 1,3-propane- diamine (MAPA) activated 2- diethylaminoethanol (DEAE) aqueous solutions were measured at temperatures ( T ) from 303.2 K to 323.2 K, respectively. The DEAE mass fractions ( w DEAE ) and the other three amines ( w AEEA / w BDA / w MAPA ) are 0.300 to 0.500 and 0.050 to 0.150 respectively. The Weiland equation was used to calculate the viscosity of these three solutions, and the calculation results were satisfied with data of the experimental results. With the aid of experimentally determined viscosity data, the activation energy ( E a) of these three solutions was predicted through the Arrhenius formula. With the help of the viscosity data and the diffusion coefficient model of CO 2 in water, the CO 2 diffusion coefficient ( D CO2 ) in these three solutions was calculated. The quantitative relationship between the calculated values (viscosity, activation energy and diffusion coefficient) and the operation conditions (solution mass fraction and temperature) was analyzed. Our results show that the DEAE-BDA absorbent has better application potential due to its lower viscosity, higher CO 2 diffusion coefficient and lower activation energy.
研究领域:
化学工程
·
环境科学
✓ 已验证
DOI
高影响因子
ANALYTICAL AND BIOANALYTICAL CHEMISTRY
·
2022
·Vol. 414
·期 5
·1881-1890
·
IF 4.478
Wu Yike,Liu Yuanyuan,Shang Zhengjun,Liu Xin,Xu Yong,Liu Wenlan
Aberrant protein N-glycosylation is one of the hallmarks of malignancy, while its role in oral cancer (OC) progression is still poorly understood making it a perfect biomarker for early-stage cancer. In this work, we describe a MALDI-MS-based N-glycomic analysis with multivariate data analysis approach for exploration and classification of the patients with OC. Various statistical analyses were used to determine differential N-glycome profiles. There were 8 glycan structures significantly increased ( p < 0.05) in all OC-derived microvesicles (MVs). Importantly, the increases in these glycans were significantly greater in the early stage of OC than those in the advanced stage of OC. Additionally, N-glycomic profiles from the serum were also performed, demonstrating a significant change of 11 glycan structures ( p < 0.05). Our data highlighted the effectiveness approach of MALDI-MS-based MV N-glycomic profiling on OC screening, and presented strong potential for further identifying targeted glycoproteomics signatures of the cancer.
研究领域:
生物化学
·
肿瘤学
·
分子生物学
✓ 已验证
DOI
PubMed
高影响因子
TOXICOLOGICAL AND ENVIRONMENTAL CHEMISTRY
·
2016
·
IF 0.634
Xirui Lv,Yue Zhou,Anguo Zhang,Lihong Zhou,Qingle Zeng
A straightforward and environment-friendly protocol for the synthesis of valuable chiral N-(tert-butylsulfinyl)imines has been developed. Different from traditional process with benzaldehydes as substrates, arylmethyl alcohols, benzylthiol, dibenzyl ether, thioether, and disulfide are used as alternative substrates to react with tert-butanesulfinamide in the presence of KOtBu under air for the synthesis of chiral N-(tert-butylsulfinyl)imines. This is a transition metal-free, mild, cost-effective, and simple process.
研究领域:
有机化学
·
环境化学
✓ 已验证
DOI
高影响因子
APPLIED ORGANOMETALLIC CHEMISTRY
·
2018
·Vol. 32
·期 10
·e4483
·
IF 3.581
Xufeng Wu,Lingyu Li,Wenlong Jiang,Lihong Zhou,Qingle Zeng
Tosylhydrazones are a kind of labile and highly reactive compounds, which are apt to be transformed into reactive diazo compounds and then into extremely reactive carbenes under the basic condition. In order to fulfil the valuable C-N coupling reaction, diaryliodonium salts are evaluated and prove to be a class of efficient electrophiles. The reaction with ligand-free copper salt as catalyst shows a wide range of substrate scope. A plausible mechanism is proposed.
研究领域:
有机化学
·
合成化学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）