57079-01-3Relevant academic research and scientific papers
Thermally reversible crosslinked polyethylene using Diels-Alder reaction in molten state
Magana, Sylvain,Zerroukhi, Amar,Jegat, Corinne,Mignard, Nathalie
, p. 442 - 448 (2010)
Thermally reversible crosslinked polyethylene was prepared by Diels-Alder (DA) and retro Diels-Alder (rDA) reaction. Maleimide/furan adduct was used as crosslinking agent. Dienophile named 11-maleimido-undecanoic acid was first synthesized and between this dienophile and commercial 3-(2-furyl) propanoic acid, the DA reaction was studied to determine DA and rDA reactions temperatures in the solid state. Then, an original modification method was employed to graft the two molecules onto the Lotader poly(ethylene-co-glycidyl methacrylate) in one step procedure. The DA and rDA reactions between diene and dienophile grafted moieties are followed by FT-IR analysis on a thin film. Readily polymer network is synthesized and the cycle of DA and retro-DA reactions is repeatable with no significant polymer degradation.
Reversible Covalent Assembly of Nanoparticles through On-Surface Diels-Alder Reaction
Schütz, Markus B.,Lê, Khan,Ilyas, Shaista,Mathur, Sanjay
, p. 1552 - 1558 (2020)
We demonstrate here a controlled assembly of individual nanoscale building blocks into defined architectures based on chemospecific covalent bonding interactions. For this purpose, α-Fe2O3, γ-Fe2O3, and SiO2 nanoparticles decorated with surface-conjugated organic ligands were used for performing on-surface Diels-Alder reactions. Driven through their chemical affinity and surface-grafted complementary functionalities, nanoparticles underwent click-reactions to produce covalently organized nanostructures. An advantage of using the Diels-Alder reaction is its reversible nature, which was used to click and unclick the nanoparticles on demand. The efficiency and chemical specificity of this approach opens up another synthetic access to unify materials with complementary properties, where the thermoresponsive nature of particle assemblies imparts to them a fully reversible character. The covalent conjugation strategies demonstrated in this work potentially allow the use of a diverse range of particles and ligands for their applications in different disciplines such as medicine, optics, or photonics. The nanoparticles morphology and crystalline nature were investigated by TEM and XRD analysis, while the presence of surface attached groups was verified by NMR, FTIR, UV-vis, and ζ potential measurements.
Synthesis N - maleic imide-based arylalkylic and its succinyl eater of method
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Paragraph 0067-0070, (2017/10/13)
The invention provides a method for synthesizing N-maleimidoalkyl acid and succinimido ester thereof, which comprises the following steps: (a) carrying out cyclization reaction on a compound disclosed as Formula (II) and phenyl 4-nitrotrifluoroacetate in an organic solvent in the presence of alkali to obtain N-maleimidoalkyl acid disclosed as Formula (III); and (b) reacting the N-maleimidoalkyl acid disclosed as Formula (III) and an acylation reagent in an organic solvent at reflux temperature to obtain an acyl chloride intermediate disclosed as (IV), reacting the acyl chloride intermediate disclosed as (IV) with N-hydroxy succinimide in an organic solvent in the presence of alkali to obtain the N-maleimidoalkyl acid succinimido ester disclosed as Formula (V). The method has the advantages of simple technique, high yield and high product purity, and is suitable for industrial production. The reaction route is disclosed in the specification.
Synthesis, characterization and properties of N-maleimide side-chain liquid crystalline copolymers
De Ojeda, J. M. Bautista,Quijada-Garrido,Barrales-Rienda
experimental part, p. 495 - 510 (2012/01/12)
A homologous series of side-chain liquid crystalline (SCLC) poly{[N-[10-((4-(((4′-n-hexyloxy)benzoyl)oxy)phenoxy)carbonyl)-n-decyl] maleimide]-co-[N-(n-octadecyl)maleimide]} [(ME6)-co-(MI-18)] random copolymers with various MI-18 contents have been synthesized and their properties studied. The high content in threo-disyndiotactic sequences of the maleimide main chain seems responsible for the stability of the highly ordered smectic mesophase. The relationship between structure and composition on thermotropic mesophase was investigated by polarizing optical microscopy, differential scanning calorimetry, and X-ray diffraction. For copolymers with mesogenic unit contents less than ～0.655 molar fraction the transition from (SA) texture to isotropic (I) is maintained, as shown by the TCl, ΔH Cl and ΔSCl amounts and intermolecular spacing 4.42-4.53 A and intralayer correlation lengths of 44.2-45.2 A. The layer thickness does not appreciably depend on copolymer composition. However, copolymers with non-mesogenic comonomer MI-18 molar contents larger than >0.655 molar fraction X(M), are no longer liquid crystalline materials, despite its packing is preserved without any detectable appearance of birefringence. Thermodynamic boundaries of the liquid crystalline state have been established through a phase diagram. The properties of this n-hexyloxy pendant group-based series are compared to those of the analogous materials containing methoxy pendant groups (ME1), and differences are accounted for in terms of the local side-chain packing within the mesophase.
NEW EFFECTOR CONJUGATES, PROCESS FOR THEIR PRODUCTION AND THEIR PHARMACEUTICAL USE
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Page/Page column 46-47, (2010/02/06)
Conjugates of epothilones and epothilone derivatives (as effectors) with suitable biomolecules (as recognition units) are described. Their production is carried out by the effectors being reacted with suitable linkers, and the compounds that are produced are conjugated to the recognition units. The pharmaceutical use of the conjugates for treating proliferative or angiogenesis-associated processes is described.
Design, synthesis, and biochemical evaluation of N-substituted maleimides as inhibitors of prostaglandin endoperoxide synthases
Kalgutkar, Amit S.,Crews, Brenda C.,Marnett, Lawrence J.
, p. 1692 - 1703 (2007/10/03)
N-(Carboxyalkyl)maleimides are rapid as well as time-dependent inhibitors of prostaglandin endoperoxide synthase (PGHS). The corresponding N- alkylmaleimides were only time-dependent inactivators of PGHS, suggesting that the carboxylate is critical for rapid inhibition. Several N-substituted maleimide analogs containing structural features similar to those of the nonsteroidal anti-inflammatory drug aspirin were synthesized and evaluated as inhibitors of PGHS. Most of the aspirin-like maleimides inactivated the cyclooxygenase activity of purified ovine PGHS-1 in a time- and concentration-dependent manner similar to that of aspirin. The peroxidase activity of PGHS was also inactivated by the maleimide analogs. The cyclooxygenase activity of the inducible isozyme, i.e., PGHS-2, was also inhibited by these compounds. The corresponding succinimide analog of N-5- maleimido-2-acetoxy-1-benzoic acid did not inhibit either enzyme activity, suggesting that inactivation was due to covalent modification of the protein. The mechanism of inhibition of PGHS-1 by N-(carboxyheptyl)maleimide was investigated. Incubation of apoPGHS-1 with 2 equiv of N-(carboxyheptyl)[3,4- 14C]maleimide led to the incorporation of radioactivity in the protein, but no adduct was detected by reversed-phase HPLC, suggesting that it was unstable to the chromatographic conditions. Furthermore, hematin- reconstituted PGHS-1, which was rapidly inhibited by N- (carboxyheptyl)maleimide, displayed spontaneous regeneration of about 50% of the cyclooxygenase and peroxidase activities, suggesting that the adduct responsible for the inhibition breaks down to regenerate active enzyme. ApoPGHS-1, inhibited by N-(carboxyheptyl)maleimide, did not display regeneration of enzyme activity, but addition of hematin to the inhibited apoenzyme led to spontaneous recovery of about 50% of cyclooxygenase activity. These results suggest that addition of heme leads to a conformational change in the protein which increases the susceptibility of the adduct toward hydrolytic cleavage. ApoPGHS-1, pretreated with N(carboxyheptyl)maleimide, was resistant to trypsin cleavage, suggesting that the carboxylate functionality of the maleimide binds in the cyclooxygenase channel. A model for the interaction of N-(carboxyheptyl)maleimide in the cyclooxygenase active site is proposed.
