MOLECULAR DIVERSITY
·
2015
·Vol. 19
·期 3
·447-458
·
IF 1.896
Niu Ben,Xie Ping,Wang Min,Wang Yanjie,Zhao Wannian,Pittman Charles U.,Zhou Aihua
A series of seven- and eight-membered ring – N,O –, – N,N –, and – N,S –sultams were effectively synthesized via tandem reactions involving oxa-, aza-, and thia-Michael addition to vinyl sulfonamides. These reactions are summarized here since they enrich current synthetic methodologies for sultams and provide a good example of sultam diversity-oriented synthesis. All reactions proceeded under relatively mild and environmentally friendly conditions, and all these reactions are quite suitable for the rapid preparation of sultam compound libraries, which are valuable for biological activity explorations.
研究领域:
有机化学
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合成化学
·
药物化学
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DOI
PubMed
高影响因子
ACS Applied Materials & Interfaces
·
2020
·
IF 8.758
Hongjun Yang,Ziye Ren,Yongkang Zuo,Yiye Song,Li Jiang,Qimin Jiang,Xiaoqiang Xue,Wenyan Huang,Kaojin Wang,Bibiao Jiang
The amide bond is one of the most pivotal functional groups in chemistry and biology. It is also the key component of proteins and widely present in synthetic materials. The majority of studies have focused on the formation of the amide group, but its postmodification has scarcely been investigated. Herein, we successfully develop the Michael additions of amide to acrylate, acrylamide, or propiolate in the presence of phosphazene base at room temperature. This amide Michael addition is much more efficient when the secondary amide instead of the primary amide is used under the same conditions. This reaction was applied to postfunctionalize poly(methyl acrylate-co-acrylamide), P(MA-co-Am), and it is shown that the amide groups of P(MA-co-Am) could be completely modified by N,N-dimethylacrylamide (DMA). Interestingly, the resulting copolymer exhibited tailorable fluorescence with emission wavelength ranging from 380 to 613 nm, which is a desired property for luminescent materials. Moreover, the emissions of the copolymer increased with increasing concentration in solution for all excitation wavelengths from 320 to 580 nm. Therefore, this work not only develops an efficient t-BuP4-catalyzed amide Michael addition but also offers a facile method for tunable multicolor photoluminescent polymers, which is expected to find a wide range of applications in many fields, such as in anticounterfeiting technology.
研究领域:
有机化学
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高分子化学
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材料科学
✓ 已验证
DOI
高影响因子
Polymers
·
2018
·Vol. 10
·期 10
·1060
·
IF 2.935
Miao-Miao Xun,Zheng Huang,Ya-Ping Xiao,Yan-Hong Liu,Ji Zhang,Ju-Hui Zhang,Xiao-Qi Yu
Rapid enzymatic degradation and fragmentation during DNA administration can result in limited gene expression, and consequently, poor efficacy. It is necessary to use novel vectors for DNA delivery. Herein, we aimed to design useful carriers for enhancing transfection efficiency (TE). These lipopolymers were prepared through Michael addition reactions from low-molecular-weight (LMW) polyethyleneimine (PEI) and linkers with three kinds of steroids. Agarose gel electrophoresis assay results displayed that the three lipopolymers could condense plasmid DNA well, and the formed polyplexes had appropriate sizes around 200–300 nm, and zeta potentials of about +25–40 mV. The results of in vitro experiments using HeLa, HEK293, and MCF-7 cells showed that these lipopolymers present higher TE than 25-kDa PEI, both in the absence and presence of 10% serum. Flow cytometry and confocal microscopy studies also demonstrated that these lipopolymer/DNA complexes present higher cellular uptake and intracellular distribution. The measurement of critical micelle concentration (CMC) revealed that these lipopolymers could form micelles, which are suited for drug delivery. All results suggest that the three materials may serve as hopeful candidates for gene and drug delivery in future in vivo applications.Keywords:gene vectors;Michael addition;lipopolymers;steroids
研究领域:
生物化学
·
分子生物学
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药学
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产品关联
DOI
PubMed
高影响因子
Journal of Coatings Technology and Research
·
2022
·Vol. 19
·期 6
·1731-1741
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IF 2.339
He Jiajian,Cheng Kai,Lin Ruijun,Su Qiuping,Li Yong,Ma Zhiping,Wang Shaoshun,Gu Yuxin,Lin Xiaofeng,Lin Wenjing,Yi Guobin
In this work, a malonate polyester suitable for Michael addition reaction was prepared by melting polycondensation of neopentyl glycol, terephthalic acid, and diethyl malonate, and its structure was characterized by Fourier transform infrared spectroscopy (FTIR) and nuclear magnetic resonance spectroscopy (NMR). Then, Michael addition reaction between malonate polyester and diphenylmethane bismaleimide (BDM), catalyzed by 1, 8-diazabicyclo [5.4.0] undec-7-ene (DBU)/benzoic acid salt, was carried out to prepare the films with different contents of curing agent. The thermal and mechanical properties of the films were characterized by dynamic thermomechanical analysis, thermogravimetric analysis, and differential scanning calorimetry. We found that glass transition temperature ( T g ) of the films increased with the increase in BDM amount. The T g could reach up to 80°C, which indicated that the fabricated films show excellent thermal stability.
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL RESEARCH IN CHINESE UNIVERSITIES
·
2021
·Vol. 38
·期 4
·968-973
·
IF 1.307
Yang Shengqing,Zhao Jinnan,Chen Shuo,Zhao Jingbo
Three new thermally responsive self-healing cross-linked polyamides(cPA-FU-DAs) with good tensile strength and toughness were synthesized through bulk Michael addition, polycondensation, and Diels-Alder reaction. Unlike common stable polymers, cPA-FU-DAs can seal cracks by mere heating. First, the Michael addition of methyl acrylate and furfurylamine was conducted, and a furfurylamine-diester(FU-DE) was prepared. FU-DE was transformed into polyamide prepolymers that contained furfuryl pendant groups(PA-FUs) through bulk polycondensation with a poly(propylene glycol)(PPG) diamine and a PPG triamine. PA-FUs were crosslinked by bismaleimide, and cPA-FU-DAs were prepared. The Michael addition was monitored by Fourier transform infrared spectroscopy and electrospray ionization mass spectroscopy. The reverse DA reaction of the cPA-FU-DAs was demonstrated by differential scanning calorimetry and dissolution property. Their thermally self-healing properties were verified by polarizing optical microscopy and tensile test. The cPA-FU-DAs exhibited good mechanical properties and high self-healing efficiency. They self-healed at 130 °C. The tensile strength after repairing was up to 19 MPa with self-healing efficiency reaching 92%.
研究领域:
材料科学
·
高分子化学
✓ 已验证
产品关联
DOI
高影响因子
POLYMER ENGINEERING AND SCIENCE
·
2022
·Vol. 62
·期 4
·1269-1280
·
IF 2.573
Shuo Chen,Yu Feng,Zhi-Yuan Zhang,Xiang-Yuan Li,Jun-Ying Zhang,Jing-Bo Zhao
Diels–Alder (DA) addition is an efficient method to repair damages at mild conditions. It is often used in self-healing polyurethanes and epoxy resins and seldom used in cross-linked polyamides (cPAs). Michael addition becomes a useful method to synthesize cPAs. However, no efficient way has been established to conduct double-addition of primary amines. In this work, organic catalyzed Michael addition and polycondensation were established to prepare polyamide oligomers with furan pendent groups (pFU-PAs), and a DA addition was adopted to prepare self-healing cross-linked polyamides (SH-cPAs). A bulk double Michael addition of furfurylamine and methyl acrylate was performed at 30–70°C in the presence of 1,5,7-triazabicyclo[4.4.0]dec-5-ene (TBD), 7-methyl-1,5,7-triazabicyclo[4.4.0]dec-5-ene (MTBD), or 4-(N,N-dimethylamino) pyridine (DMAP), and a high yield of furfurylamine-N,N-bis(methyl propionate) (FA-BMP) was prepared. The catalytic activity order is MTBD>TBD >>DMAP in Michael addition. Melt polycondensation of FA-BMP with bis(2-aminopropyl) polypropyleneglycol and hexamethylene diamine was catalyzed by MTBD and N,N′-diphenylthiourea. The DA addition of 1,5-bismaleimido-2-methylpentane and pFU-PAs was monitored by FT-IR, 1 H NMR, DSC, polarizing optical microscopy, and gel content. In these catalyzed processes, the structures of FA-BMP, pFU-PAs, and SH-cPAs were controlled easily, and the SH-cPAs showed good mechanical property and excellent self-healing performance of 88%–98%.
研究领域:
材料化学
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高分子科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF CHEMICAL TECHNOLOGY AND BIOTECHNOLOGY
·
2012
·Vol. 87
·期 12
·1709-1714
·
IF 2.168
Bang-Hua Xie,Zhi Guan,Yan-Hong He
BACKGROUND: Biocatalytic promiscuity has attracted much attention from chemists and biochemists in recent years. Warfarin, one of the most effective anticoagulants, has been introduced for clinical use as a racemate for more than half a century. Although some different chemical strategies towards the synthesis of optically active warfarin have been reported, biocatalytic preparation of warfarin remains unexploited. RESULTS: Lipase from porcine pancreas (PPL) was used as a biocatalyst to catalyze the Michael addition of 4-hydroxycoumarin to α,β-unsaturated enones in organic medium in the presence of water to synthesize warfarin and derivatives. The products were obtained in moderate to high yields (up to 95%) with none or low enantioselectivities (up to 28% ee). The influence of reaction conditions including solvents, temperature and molar ratio of substrates was systematically investigated. CONCLUSION: Among the many reported lipase-catalyzed Michael additions, only a few showed enantioselectivity. Therefore, this Michael addition activity of, for example, PPL is a valuable case of enantioselective lipase catalytic promiscuity. In addition, it was the first time warfarin and derivatives were prepared using a biocatalyst. Copyright © 2012 Society of Chemical Industry
研究领域:
生物化学
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药物化学
✓ 已验证
产品关联
DOI
高影响因子
MOLECULES
·
2018
·Vol. 23
·期 9
·2154
·
IF 3.098
Yunchang Fan,Dongxu Cai,Xin Wang,Lei Yang
Recently, ionic liquids (ILs) have been regarded as ideal media for non-aqueous bio-catalysis. In this work, the synthesis of warfarin by the lipase-catalyzed Michael addition in IL media and the parameters that affected the warfarin yield were investigated. Experimental results demonstrated that the chemical structures of the ILs were a major factor for influencing the warfarin yield. The ILs containing the NTf2–anion were suitable reaction media due to the high chemical stability of this anion. The incorporation of the hydroxyl group on the IL cation significantly improved the lipase activity due to the H2O-mimicking property of this group. The lipase activity decreased by increasing the alkyl chain length on the IL cation due to the non-polar domain formation of the IL cation at the active site entrance of lipase. The ILs and lipase could be reused no less than five times without reduction in the warfarin yield.Keywords:ionic liquids (ILs);lipase;Michael addition;warfarin;bio-catalysis
研究领域:
生物化学
·
制药工程
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产品关联
DOI
PubMed
高影响因子
Catalysts
·
2020
·Vol. 10
·期 4
·432
·
IF 3.52
Li-Hua Du,Rui-Jie Long,Miao Xue,Ping-Feng Chen,Meng-Jie Yang,Xi-Ping Luo
A continuous-flow procedure for the synthesis of β-amino acid esters has been developed via lipase-catalyzed Michael reaction of various aromatic amines with acrylates. Lipase TL IM fromThermomyces lanuginosuswas first used to catalyze Michael addition reaction of aromatic amines. Compared with other methods, the salient features of this work include green reaction conditions (methanol as reaction medium), short residence time (30 min), readily available catalyst and a reaction process that is easy to control. This enzymatic synthesis of β-amino acid esters performed in continuous-flow microreactors is an innovation that provides a new strategy for the fast biotransformation of β-amino acid esters.Keywords:enzymatic synthesis;β-amino acid esters;microreactor;aromatic amines;Michael addition
研究领域:
生物化学
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有机化学
✓ 已验证
产品关联
DOI
高影响因子
FIBERS AND POLYMERS
·
2017
·Vol. 18
·期 9
·1763-1768
·
IF 1.113
Liang Liping,Huang Yimeng,Zhan Haihua,Xi Bojun,Meng Xu
An oil/water separation cotton fabric with high separation efficiency has been successfully developed by combining mussel-inspired one-step copolymerization approach and Michael addition reaction. The cotton fabric was first coated with the adhesive polydopamine (PDA) film by simple immersion in an aqueous solution of dopamine at pH of 8.5. Then n-dodecyl mercaptan (NDM) was conjugated with PDA film through Michael addition reaction at ambient temperature. The chemical structure, surface topography, and surface wettability of the fabric were characterized by Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy, and contact angle experiments, respectively. The results showed that as-prepared cotton fabric had highly hydrophobicity with the water contact angle of 145° and superoleophilicity with the oil contact angle of 0°. It exhibited desirable property of oil/water separation, and it had excellent potential to be used in practical applications and has created a new field for oil/water separation.
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
RESEARCH ON CHEMICAL INTERMEDIATES
·
2012
·Vol. 38
·期 7
·1699-1705
·
IF 0.697
Xie Wen Lin,Xiao Chuang Ping,Xie Ling,Zhou Ying,Li Xue Feng,Tang Xu Fu,Yuan Chun Tao,Qiu Ming Hua
4 - Substituted 3-hydroxy-2(1 H )-pyridinones 2 were prepared by Mannich reaction of 3-hydroxy-2(1 H )-pyridinones with secondary amines and formaldehyde. The isolated products were then reacted with aromatic amines in the presence of NaIO 3 as oxidant via oxidation–Michael addition to yield 4,5,6-trisubstituted-2,3-pyridinediones 3 in good yields (80.2–88.9%). The structures of the products were characterized by 1 H NMR, ESI-MS, and IR, and elemental analysis.
研究领域:
有机化学
·
药物化学
✓ 已验证
DOI
高影响因子
ANALYTICAL CHEMISTRY
·
2017
·
IF 6.32
Yanqiu Song,Jialei Bai,Rong Zhang,Houluo He,Chao Li,Jiang Wang,Shuang Li,Yuan Peng,Baoan Ning,Minglin Wang,Zhixian Gao
Abuse of antibiotics results in a large number of antibiotics residues in the environment and even causes the problem of “super bacteria”. Therefore, it is crucial to develop a powerful analytic method to monitor antibiotics quickly and simply. Photonic crystal (PC), as a sensing material, has promising application prospects. Herein, we try to use PC to realize pretreatment-free and label-free detection of Ciprofloxacin (CF) through Michael addition reaction. The recognition process is carried out by the Michael addition reaction between the piperazine group of CF and the o-benzoquinone group on the PC. The monodisperse microspheres with o-benzoquinone groups are prepared by polymerization and oxidation and then stacked to form PC. During the detection, the peak intensity of the PC decreases with the increasing CF concentration, and the linear range is from 2 to 512 μg/L. The limit of detection (LOD) is 0.76 μg/L. Furthermore, the PC retains 97% of the initial response after storage in a Petri dish at room temperature for 1 month, which shows that it has good stability. Moreover, CF in fish farming water can be detected directly without any pretreatment and label, and the results are in good accordance with the LC-MS-MS results. This Michael-addition-mediated PC is accurate, easily prepared, cost-efficient, and long-term stable. In addition, it is environmentally friendly, because little organic solvent is needed during both the preparation and the detection.
研究领域:
环境科学
·
分析化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）