- Efficient synthesis of isoxazolidine-tethered monolayer-protected gold nanoparticles (MPGNs) via 1,3-dipolar cycloadditions under high-pressure conditions
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(Chemical Equation Presented) A maleimide-modified 2.5 ± 0.5 nm mixed monolayer protected gold nanoparticle (2-C12MPGN) containing approximately 30% maleimide-terminated dodecanethiolate/dodecanethiolate ligands was prepared. The 2-C12MPGN was reacted with a series of nitrones (a-i) at both atmospheric and hyperbaric (11 000 atm) conditions to form the corresponding isoxazolidine-modified nanoparticles (3-C12MPGN) via an interfacial 1,3-dipolar cycloaddition. At atmospheric pressures, the reaction proceeds slowly (if at all) and makes this reaction impractical for the synthetic modification of the nanoparticles. However, by performing the reaction under the high-pressure conditions, the reaction proceeds efficiently and quantitatively. TEM shows that the use of high pressure does not affect the size of the gold nanoparticle core. The 3-C12MPGNs were characterized by 1H NMR spectroscopy by comparing the spectra obtained with those of model reactions utilizing N-dodecylmaleimide (4) with the same nitrones (a-i) to form 5. Additionally, the cycloaddition reaction also occurs more readily with 4 than with 2-C12MPGN with all nitrones, indicating that the environment of the latter affects the cycloaddition reaction.
- Zhu, Jun,Lines, Brandon M.,Ganton, Michael D.,Kerr, Michael A.,Workentin, Mark S.
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- Synthesis and biological activity of a squalenoid maleimide and other classes of squalene derivatives as irreversible inhibitors of 2,3-oxidosqualene cyclase
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New classes of squalene derivatives were rationally designed and synthesized as irreversible inhibitors of 2,3-oxidosqualene cyclase (OSC), a key enzyme in sterol biosynthesis. The derivatives synthesized were maleimide 5, disulfides 8-9, α,β-unsaturated nitriles 10-11 and oxirane 12. The inhibitor activities of these derivatives were determined in vitro on OSC associated with pig liver microsomes. Squalene and dodecyl maleimide were the best inhibitors of OSC, showing a time-dependent enzyme inactivation. Moreover 2,3-oxidosqualene (OS), the natural substrate of OSC, partially protected the enzyme from squalene maleimide inactivation whereas the dodecyl derivative did not. This fact and the complex kinetics shown by squalene maleimide suggest the presence of different classes of thiolic groups essential to the activity of OSC.
- Grosa,Viola,Ceruti,Brusa,Delprino,Dosio,Cattel
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- A fluorescence "turn-on" ensemble for acetylcholinesterase activity assay and inhibitor screening
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By making use of the aggregation-induced emission feature of compound 1 and the cascade reactions among acetylthiocholine iodide (ATC), AChE, and compound 2, a new fluorescence "turn-on" method is developed for AChE assay and inhibitor-screening.
- Peng, Lihua,Zhang, Guanxin,Zhang, Deqing,Xiang, Junfeng,Zhao, Rui,Wang, Yilin,Zhu, Daoben
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- Anti-leishmanial and cytotoxic activities of a series of maleimides: Synthesis, biological evaluation and structure-activity relationship
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In the present study, 45 maleimides have been synthesized and evaluated for anti-leishmanial activities against L. donovani in vitro and cytotoxicity toward THP1 cells. All compounds exhibited obvious anti-leishmanial activities. Among the tested compounds, there were 10 maleimides with superior anti-leishmanial activities to standard drug amphotericin B, and 32 maleimides with superior anti-leishmanial activities to standard drug pentamidine, especially compounds 16 (IC50 50 50 > 10 μg/mL). The anti-leishmanial activities of 16 and 42 were 10 times better than that of amphotericin B. The structure and activity relationship (SAR) studies revealed that 3,4-non-substituted maleimides displayed the strongest anti-leishmanial activities compared to those for 3-methyl-maleimides and 3,4-dichloro-maleimides. 3,4-dichloro-maleimides were the least cytotoxic compared to 3-methyl-maleimides and 3,4-non-substituted maleimides. The results show that several of the reported compounds are promising leads for potential anti-leishmanial drug development.
- Fan, Yongxian,Lu, Yuele,Chen, Xiaolong,Tekwani, Babu,Li, Xing-Cong,Shen, Yinchu
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- MANUFACTURING METHOD OF N-SUBSTITUTED MALEIMIDE
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PROBLEM TO BE SOLVED: To provide a manufacturing method of N-substituted maleimide which can manufacture the N-substituted maleimide having long-chain alkyl groups efficiently even if amine having long-chain alkyl groups are used as a raw material. SOLUTION: A manufacturing method of N-substituted maleimide includes a step reacting maleic anhydride and amine in a solvent mixture containing aromatic organic solvent and alicyclic organic solvent and/or aliphatic organic solvent which carbon number is 8-18. SELECTED DRAWING: None COPYRIGHT: (C)2018,JPOandINPIT
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Paragraph 0061-0064; 0065-0066; 0067-0068
(2018/04/06)
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- A novel glucagon-like peptide-1/glucagon receptor dual agonist exhibits weight-lowering and diabetes-protective effects
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Glucagon has plenty of effects via a specific glucagon receptor(GCGR) like elevating the blood glucose, improving fatty acids metabolism, energy expenditure and increasing lipolysis in adipose tissue. The most important role of glucagon is to regulate the blood glucose, but the emergent possibilities of hyperglycaemia is exist. Glucagon could also slightly activate glucagon-like peptide-1 receptor(GLP-1R), which lead to blood glucose lowering effect. This study aims to erase the likelihood of hyperglycaemia and to remain the inherent catabolic effects through improving GLP-1R activation and deteriorating GCGR activation so as to lower the bodyweight and show diabetes-protective effects. Firstly, twelve cysteine modified GLP-1/GCGR dual agonists were synthesized (1–12). Then, the GLP-1R/GCGR mediated activation and biological activity in normal ICR mice were comprehensively performed. Compounds substituted by cysteine at positions 22, 23 and 25 in glucagon were observed to be better regulators of the body weight and blood glucose. To prolong the half-lives of derivatives, various fatty side chain maleimides were modified to optimal glucagon analogues. Laurate maleimide conjugate 4d was the most potent. Administration of 1000 nmol/kg 4d once every two days for a month normalized adiposity and glucose tolerance in diet-induced obese (DIO) mice. Improvements in plasma metabolic parameters including insulin, leptin, and adiponectin were observed. These studies suggest that compound 4d behaves well in lowering body weight and maintaining energy expenditure without a chance of hyperglycaemia, 4d has strong clinical potential as an efficient GLP-1/GCGR agonist in the prevention and treatment of obesity and dyslipidemia.
- Zhou, Jie,Cai, Xingguang,Huang, Xun,Dai, Yuxuan,Sun, Lidan,Zhang, Bo,Yang, Bo,Lin, Haiyan,Huang, Wenlong,Qian, Hai
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p. 1158 - 1169
(2017/08/02)
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- Study of the diels-alder and retro-diels-alder reaction between furan derivatives and maleimide for the creation of new materials
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The Diels-Alder reaction leads to a mixture of two diastereomers, one called endo and the other one exo. The cyclo-reversion temperature of the first one is lower than the exo adduct and the ratio between endo and exo adducts varies according to the substituents of the Diels-Alder partners and experimental parameters. Therefore, the influence of some reaction parameters such as the substituents of furan and maleimide derivatives, the reaction temperature and the presence of a nucleophile on the endo/exo Diels-Alder ratio and/or the retro-Diels-Alder reaction have been studied. For instance, furan and maleimide derivatives with electron withdrawing substituents induced the creation of the endo adduct preferentially. Also the presence of a far electron withdrawing substituent on furan and/or an electron attracting mesomeric substituent on maleimide resulted in a faster reversibility of the endo adduct. Finally, a high temperature and the presence of a nucleophile (thiol) also induced faster retro-Diels-Alder kinetics. Moreover, it was proved that isomerization from the endo to the exo diastereomer is preceded by a retro-Diels-Alder reaction of the endo adduct. The presence of a nucleophile in the mixture confirmed this result. This study allowed the highlighting of different parameters of the Diels-Alder reaction to obtain as much endo adduct as possible, and a fast and/or full retro-Diels-Alder reaction of this adduct.
- Froidevaux,Borne,Laborbe,Auvergne,Gandini,Boutevin
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p. 37742 - 37754
(2015/05/13)
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- Synthesis and fluorescent properties of model compounds for conjugated polymer containing maleimide units at the main chain
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2,3-Diaryl substituted maleimides as model compounds of conjugated maleimide polymers [poly(RMI-alt-Ar) and poly(RMI-co-Ar)] were synthesized from 2,3-dibromo-N-substituted maleimide (DBrRMI) [R= cyclohexyl (DBrCHMI) and n-hexyl (DBrHMI)] and aryl boronic acid using palladium catalysts. To clarify structures of conjugated polymer containing maleimide units at the main chain, 13C NMR spectra of 2-aryl or 2,3-diaryl substituted maleimides were compared with those of N-substituted maleimide polymers. Copolymers obtained with DBrRMI via Suzuki-Miyaura cross-coupling polymerizations or Yamamoto coupling polymerizations were dehalogenated structures at the terminal end. This dehalogenation may contribute to the low polymerizability of DBrRMIs. On the other hand, the π-conjugated compounds showed high solubility in common organic solvents. The N-substituents of maleimide cannot significantly affect the photoluminescence spectra of 2,3-diaryl substituted maleimides derivatives. The fluorescence spectra of poly(RMI-alt-Ar) and poly(RMI-co-Ar) varied with N-substituents of the maleimide ring. When exposed to ultraviolet light of wavelength 352 nm, a series of 1,4-phenylene- and/or 2,5-thienylene-based copolymers containing N-substituted maleimide derivatives fluoresced in a yellow to blue color. It was found that photoluminescence emissions and electronic state of π-conjugated maleimide derivatives were controlled by aryl- and N-substituents, and maleimide sequences of copolymers.
- Onimura, Kenjiro,Matsushima, Mieko,Nakamura, Munetoshi,Tominaga, Tatsuya,Yamabuki, Kazuhiro,Oishi, Tsutomu
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scheme or table
p. 3550 - 3558
(2012/05/19)
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- Chemical modification of monolayer-protected gold nanoparticles using hyperbaric conditions
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Sluggish or impractical Diels-Alder reactions of a maleimide modified-MPN with a series of dienes of varying electronic and steric demands at ambient pressure and temperature proceed under hyperbaric conditions in less than 10 min without altering the gold core of the nanoparticle or its inherent physical properties. Copyright
- Zhu, Jun,Ganton, Michael D.,Kerr, Michael A.,Workentin, Mark S.
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p. 4904 - 4905
(2008/02/01)
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- Process for preparation of N-substituted maleimides
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N-substituted maleimide represented by formula (2): STR1 is produced from N-substituted maleamic acid monoester represented by formula (1): STR2 in the presence of an acid catalyst by elmination of an alcohol from the monoester. The above N-substituted maleamic acid monoester represented by formula (1) is produced by esterification of N-substituted maleamic acid represented by formula (3): STR3 with an alcohol R2 -OH in the represence of an acid catalyst.
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