- Superior chemotherapeutic benefits from the ruthenium-based anti-metastatic drug NAMI-A through conjugation to polymeric micelles
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Macromolecular ruthenium complexes are a promising avenue to better, and more selective, chemotherapeutics. NAMI-A is a ruthenium(III) drug in Phase II clinical trials that has low cytotoxicity and is inactive against primary tumors. However, it displays both antiangiogenic and anti-invasive properties and has been shown to specifically target tumor metastases, preventing both development and growth. To increase the cytotoxicity and cell uptake of this promising drug, we designed a biocompatible amphiphilic block copolymer capable of self-assembling into polymeric micelles. An appropriate method for the synthesis of a macromolecular NAMI-A drug was identified - the polymerization of vinyl imidazole and subsequent addition of a ruthenium(III) precursor complex. The cytotoxicity of these polymeric moieties was tested on ovarian cancer A2780 and Ovcar-3 and pancreatic AsPC-1 cancer cell lines. On average, across the tested cell lines, a 1.5 times increase in toxicity was found for the NAMI-A copolymer micelles when compared to the NAMI-A molecule. Furthermore, the antimetastatic potential was assessed by evaluating the inhibitory effects on the migration and invasion of cells against three cell lines characterized by differing degrees of malignancy (MDA-MB-231 > MCF-7 > CHO). The NAMI-A micelles were shown to have an improved antimetastatic potential in comparison to NAMI-A.
- Blunden, Bianca M.,Rawal, Aditya,Lu, Hongxu,Stenzel, Martina H.
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- Bioinspired Imprinted PHEMA-Hydrogels for ocular delivery of carbonic anhydrase inhibitor drugs
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Hydrogels with high affinity for carbonic anhydrase (CA) inhibitor drugs have been designed trying to mimic the active site of the physiological metallo-enzyme receptor. Using hydroxyethyl methacrylate (HEMA) as the backbone component, zinc methacrylate, 1- or 4-vinylimidazole (1VI or 4VI), and N-hydroxyethyl acrylamide (HEAA) were combined at different ratios to reproduce in the hydrogels the cone-shaped cavity of the CA, which contains a Zn 2+ ion coordinated to three histidine residues. 4VI resembles histidine functionality better than 1VI, and, consequently, pHEMA-ZnMA 2 hydrogels bearing 4VImoietieswere those with the greatest ability to host acetazolamide or ethoxzolamide (2 to 3 times greater network/water partition coefficient) and to sustain the release of these antiglaucoma drugs (50%lower release rate estimated by fitting to the square root kinetics). The use of acetazolamide as template during polymerization did not enhance the affinity of the network for the drugs. In addition to the remarkable improvement in the performance as controlled release systems, the biomimetic hydrogels were highly cytocompatible and possessed adequate oxygen permeability to be used as medicated soft contact lenses or inserts. The results obtained highlight the benefits of mimicking the structure of the physiological receptors for the design of advanced drug delivery systems.
- Ribeiro, Andreza,Veiga, Francisco,Santos, Delfim,Torres-Labandeira, Juan J.,Concheiro, Angel,Alvarez-Lorenzo, Carmen
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- Imidazole polymers derived from ionic liquid 4-vinylimidazolium monomers: Their synthesis and thermal and dielectric properties
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The synthesis of 1-ethyl-3-methyl-4-vinylimidazolium triflate, its polymerization, and ion exchange to yield a family of 4-imidazolium polymers with a variety of anions are described. For comparative purposes, the synthesis, polymerization, and ion exchange of an analogous set of 1-vinylimidazolium polymers are also presented. The comparative thermal and dielectric characteristics of the 4-vinyl- and 1-vinylimidazolium salts were evaluated. The trends in the glass transition (Tg) characteristics of the various 4-vinylimidazolium and 1-vinylimidazolium polymers were similar; however, the glass transition temperatures of poly(4-vinylimidazolium) BF4 -, PF6-, AsF6-, and CF3SO3- salts were significantly higher than those of the corresponding poly(1-vinylimidazolium) salts. This difference and the increase in Tg in going from BF4- to AsF6- in the 4-vinylimidazolium series were attributed to enhanced intramolecular bridging between imidazolium moieties positioned 1,3 or 1,5 along the polymer chain. In the dielectric spectra of 1-vinylimidazolium salts at temperatures in excess of 30 C, one relaxation mode distinct from that for electrode polarization is observed. The single mode appears to correspond to the α-relaxation peak in poly(3-ethyl-1-vinylimidazolium salts) recently identified and attributed to ion-pair motion by Nakamura et al. In the 4-vinylimidazolium polymer spectra set, at temperatures in excess of 30 C, two relaxation modes, distinct from that for electrode polarization, are apparent: the α peak also observed in the 1-vinylimidazolium polymer set and a new relaxation peak observed at lower frequency. The lower frequency relaxation peak is identified in this work as the α′-relaxation and is also associated with ion-pair motion. Assuming the relaxation processes to be Arrhenius in nature, the activation energy of the α-relaxation in poly(4-vinylimidazolium) BF4-, PF6-, CF3SO3-, TFSI-, and C 2N3- salts ranged from 83 to 28 kJ/mol and appears to scale with the glass transition temperature.
- Smith, Thomas W.,Zhao, Meng,Yang, Fan,Smith, Darren,Cebe, Peggy
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- High oxygen-binding affinity of poly(4-vinylimidazole-co-octylmethacrylate)-cobaltporphyrin complex: effect of hydrogen-bond at the imidazole residue
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The oxygen-binding affinity of the cobalt-picketfence-porphyrin (CoP) ligated with imidazole was enhanced in the presence of an additive which forms a hydrogen-bond with the ligated imidazole. The CoP complex with poly(4(5)-vinylimidazole-co-octylmethacrylate) rapidly and reversibly bound oxygen and showed very high oxygen-binding affinity: The oxygen transport in the CoP-polymer membrane was efficiently facilitated.
- Nishide, Hiroyuki,Kato, Aiko,Tsuchida, Eishun
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- Functionalization of the Imidazole Backbone by Means of a Tailored and Optimized Oxidative Heck Cross-Coupling
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A general and selective Pd-catalyzed cross-coupling of aromatic boronic acids with vinyl-imidazoles is disclosed. Unlike most cross-coupling reactions, this method operates well in absence of bases avoiding the formation of by-products. The reactivity is highly enhanced by the presence of nitrogen-based ligands, in particular bathocuproine. The method involves MnO2 as oxidant for the oxidation Pd (0)→Pd (II), a much weaker oxidant than previously reported in the literature. This allows for the use of reactants that possess a multitude of functional groups. A scope and limitation study involving a series of 24 boronic acids, whereof 18 afforded TMs in yields in the range 41–95%. The disclosed method constitutes the first general method for the oxidative Heck cross-coupling on the imidazole scaffold, which moreover operates with a selection of other heterocycles. (Figure presented.).
- Cirillo, Davide,Angelucci, Francesco,Bj?rsvik, Hans-René
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p. 5079 - 5092
(2020/09/23)
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- Design and characterization of a heterocyclic electrophilic fragment library for the discovery of cysteine-targeted covalent inhibitors
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A fragment library of electrophilic small heterocycles was characterized through cysteine-reactivity and aqueous stability tests that suggested their potential as covalent warheads. The analysis of theoretical and experimental descriptors revealed correlations between the electronic properties of the heterocyclic cores and their reactivity against GSH that are helpful in identifying suitable fragments for cysteines with specific nucleophilicity. The most important advantage of these fragments is that they show only minimal structural differences from non-electrophilic counterparts. Therefore, they could be used effectively in the design of targeted covalent inhibitors with minimal influence on key non-covalent interactions.
- Keeley,ábrányi-Balogh,Keseru
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supporting information
p. 263 - 267
(2019/03/05)
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- Asymmetric Organocatalytic Synthesis of Bisindoles – Scope and Derivatizations
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Starting from 3-vinylindoles and glyoxolate imines, we created a library of diverse 4,6-bis(1H-indole-3-yl)piperidine 2-carboxylates by using 10 mol-% of a chiral phosphoric acid. Utilising electron-withdrawing groups on the starting material during the r
- Retich, Christina,Br?se, Stefan
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supporting information
p. 60 - 77
(2018/01/17)
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- Thermal 1,3-Trityl migrations in diels-alder domino reactions of 1-Trityl-4-vinyl-1 H-imidazoles
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(Figure presented) Under thermal conditions, tritylimidazoles have been shown to undergo sterically driven N→N trityl migrations, in disagreement with previously published reports. These migrations are a key step in several highly diastereoselective domin
- Cotterill, Lynsey J.,Harrington, Ross W.,Clegg, William,Hall, Michael J.
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supporting information; experimental part
p. 4604 - 4607
(2010/10/02)
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- High rates and substrate selectivities in water by polyvinylimidazoles as transaminase enzyme mimics with hydrophobically bound pyridoxamine derivatives as coenzyme mimics
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(Chemical Equation Presented) Free-radical polymers of 4-vinylimidazole and copolymers with 1-dodecyl-4-vinylimidazole were used as enzyme mimics to transaminate pyruvic acid to alanine, phenylpyruvic acid to phenylalanine, and indole-3-pyruvic acid to tryptophan in water at pH 7.5 and 20 °C using pyridoxamines carrying hydrophobic side chains as coenzyme mimics. The best enzyme mimic accelerated the transamination of indole-3-pyruvic acid by a factor of 4 million relative to the rate without the polymer, a higher rate ratio than we had previously achieved with a polyaziridine-based enzyme mimic. The properties of various polyvinylimidazoles were compared, including those prepared with the RAFT modification of the polymerization process.
- Skouta, Rachid,Wei, Sujun,Breslow, Ronald
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supporting information; experimental part
p. 15604 - 15605
(2010/01/30)
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- TRIAZINE COMPOUNDS AS KINASE INHIBITORS
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The present invention relates to triazine compounds that are useful as kinase inhibitors. More particularly, the present invention relates to morpholino substituted triazines, methods for their preparation, pharmaceutical compositions containing these compounds and uses of these compounds in the treatment of proliferative disorders. These compounds may be useful as medicaments for the treatment of a number of proliferative disorders including tumours and cancers as well as other disorders or conditions related to or associated with mTOR kinases or PI3 kinases. The compounds are of the formula (I)
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Page/Page column 97-98
(2009/09/05)
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- The kulinkovich reaction in the synthesis of constrained N,N-dialkyl neurotransmitter analogues
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An intermolecular Ti(IV)-mediated cyclopropanation reaction has been used to synthesize substituted 2-phenylcyclopropylamines and constrained analogues of the neurotransmitters histamine and tryptamine. Many hydroxy- and methoxy-substituted phenylcyclopropylamines are known to inhibit monoamine oxidase and have been shown to mimic hallucinogens. These compounds were made in 1 to 5 steps from readily available starting materials.
- Faler, Catherine A.,Joullie, Madeleine M.
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p. 1987 - 1990
(2008/02/02)
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- 4(5)-Vinylimidazole by Dehydrobromination of 1-Triphenylmethyl-4-(2-bromoethyl)imidazole
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1-Triphenylmethyl-4-(2-bromoethyl)imidazole undergoes elimination upon basic treatment providing an approach to 4(5)-vinylimidazole whereas the N-unsubstituted analogue leads only to substitution products.
- Altman, Janina,Wilchek, Meir
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p. 915 - 916
(2007/10/02)
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- IMPROVED SYNTHESES OF VINYL IMIDAZOLES
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A series of vinylimidazoles were synthesized via Witting reactions on N-tritylimidazole-4-carboxaldehyde.Activated phosphonate ylids afforded yields in excess of 90percent while the yields from unactivated ylids ranged from 10-82percent.The trityl group m
- Griffith, Robert K.,DiPietro, Richard A.
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p. 1761 - 1770
(2007/10/02)
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- The Structure of +. and + Ions Formed from Vinylimidazoles, Studied by Collisionally Activated Dissociation Mass Spectrometry
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Mass spectra of the three isomeric vinylimidazoles have been compared and the structures of the fragment ions +. and + have been investigated by collisionally activated dissociation mass spectrometry.The greater part of the non-decomposing ions m/z 68 from 2-vinylimidazole and from 2-imidazolecarboxylic acid methyl ester, and a minor part of this ion formed from the free acid, all have the same structure: the imidazole ring system, with hydrogens at both nitrogen atoms but none at C(2).An analogous structure, with an ethynyl group at C(2), is proposed for the m/z 93 ion from 2-vinylimidazole.
- Tilborg, M. W. E. M. van,Houte, J. J.,Thuijli, J. van
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