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31.
Cytotoxic Activity and Structure–Activity Relationship of Triazole‐Containing Bis(Aryl Ether) Macrocycles 下载免费PDF全文
Dr. Eduardo Hernández‐Vázquez Dr. Alejandra Chávez‐Riveros Dr. Adriana Romo‐Pérez María Teresa Ramírez‐Apán Dr. Alma D. Chávez‐Blanco Dr. Rocío Morales‐Bárcenas Dr. Alfonso Dueñas‐González Dr. Luis D. Miranda 《ChemMedChem》2018,13(12):1193-1209
Cancer continues to be a worldwide health problem. Certain macrocyclic molecules have become attractive therapeutic alternatives for this disease because of their efficacy and, frequently, their novel mechanisms of action. Herein, we report the synthesis of a series of 20‐, 21‐, and 22‐membered macrocycles containing triazole and bis(aryl ether) moieties. The compounds were prepared by a multicomponent approach from readily available commercial substrates. Notably, some of the compounds displayed interesting cytotoxicity against cancer (PC‐3) and breast (MCF‐7) cell lines, especially those bearing an aliphatic or a trifluoromethyl substituent on the N‐phenyl moiety (IC50<13 μm ). Additionally, some of the compounds were able to induce apoptosis relative to the solvent control; in particular, (Z)‐N‐cyclohexyl‐7‐oxo‐6‐[4‐(trifluoromethyl)phenyl]‐11H‐3,10‐dioxa‐6‐aza‐1(4,1)‐triazola‐4(1,3),9(1,4)‐dibenzenacyclotridecaphane‐5‐carboxamide ( 12 f ) was the most potent in this regard (22.7 % of apoptosis). 相似文献
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33.
Influence of ionic liquid composition on the stability of polyvinyl chloride‐based ionic liquid inclusion membranes in aqueous solution 下载免费PDF全文
Francisca Tomás‐Alonso Aurora M. Rubio Alfonso Giménez Antonia P. de los Ríos Maria J. Salar‐García Victor M. Ortiz‐Martínez Francisco J. Hernández‐Fernández 《American Institute of Chemical Engineers》2017,63(2):770-780
Membrane technology has gained significant importance with the incorporation of ionic liquids into their structure. This work shows the influence of ionic liquid composition on the stability of PVC‐based polymer ionic liquid inclusion membranes (PILIMs) in aqueous solution. Among the ILs investigated, those membranes which contain between 20 and 30%w/w of the least soluble, [OMIM+][PF6?] and [OMIM+][Ntf2?], exhibit losses of IL lower than 10%. For both ILs, the amount immobilized was maximum for the membranes with 30%w/w of IL (0.0838 and 0.0832 g, respectively). On the contrary, the ionic liquid loss increases as its solubility in water increase, reaching 99.52% when PILIMs are prepared with 70%w/w of [OMIM+][BF4?]. The results demonstrate that the stability of PILIMs depends on the solubility of the IL in the surrounding phase and the specific interaction between the IL and the polymeric support for PVC‐to‐IL ratios higher than 30%w/w. © 2016 American Institute of Chemical Engineers AIChE J, 63: 770–780, 2017 相似文献
34.
Electrospun nanofibers of a degradable poly(ester amide). Scaffolds loaded with antimicrobial agents
Luis J. del Valle Manuel Roa Angélica Díaz María T. Casas Jordi Puiggalí Alfonso Rodríguez-Galán 《Journal of Polymer Research》2012,19(2):9792-13
Electrospinning conditions were evaluated to prepare micro/nanofibers of a biodegradable poly(ester amide) constituted by
L-alanine, 1,12-dodecanediol and sebacic acid. 1,1,1,3,3,3-Hexafluroroisopropanol appeared as the most appropriate solvent
to obtain fibers in a wide range of electrospinning conditions that allowed tuning the final diameter size. Fiber diameter
increased with the flow, distance between the needle tip and the collector and decreasing voltage, which made it possible
to obtain homogeneous fibers in the 1700–320 nm range. Fibers were loaded with antimicrobial agents like silver and chlorohexidine,
and the influence of agent concentration in the electrospinning solutions on the fiber diameter size was determined. The polymer
was able to crystallize during the electrospinning process, giving rise to a structure slightly different from that obtained
by solution crystallization and related to that attained after crystallization from the melt state. Addition of antimicrobial
agents had little effect on the degree of crystallinity, although it decreased slightly when chlorhexidine was employed. Scaffolds
prepared from the silver and chlorhexidine loaded samples supported cell adhesion and proliferation. Furthermore, a clear
and well differentiated antimicrobial effect against both Gram-positive (e.g. M. luteus) and Gram-negative (e.g. E. coli) bacteria was demonstrated. 相似文献
35.
Alfonso Policicchio Raffaele Filosa Salvatore Abate Giovanni Desiderio Elio Colavita 《Journal of Porous Materials》2017,24(4):905-922
The aim of this comprehensive review on materials for methane storage application is to understand which are the best conditions and the best materials for their use for the implementation of storage tank. The research was focused on two different families of samples that up to now appear like the most promising. In particular, Activated carbon and metal organic framework were analyzed and an overall picture was extrapolated. Analysis of the structural parameters and adsorption capacities were evaluated and relation between them were obtained. A comparison of values available in literature was done and, when possible, laboratory tests were performed. The presented results allow to identify potential materials with high specific storage capacity and to verify their performances in optimized conditions. This work represents the starting point for a real and efficient method to the methane storage as a starting point for the development of Adsorbed Natural Gas technology for static and/or automotive applications. 相似文献
36.
Elisa G. Doyagüez Francisco Parra Guillermo Corrales Alfonso Fernndez-Mayoralas Alberto Gallardo 《Polymer》2009,50(19):4438-4446
The synthesis of two new types of methacrylic polybetaines bearing trans-4-hydroxy-l-proline connected via its hydroxyl group is described, one with an aliphatic spacer of 6 carbon atoms and the other without any spacer. The pH sensitivity in aqueous media and the catalytic activity of the products in asymmetric aldol additions have been studied. The two polyzwitterions show an isoelectric point (IEP) close to 3. Swelling of networks prepared with the two monomers exhibit reversible pH sensitivity; the largest the pH distance from the IEP, the higher the net charge (positive or negative) and the higher the swelling. At basic pH and an ionic strength of 0.15, maximum swelling degrees of around 11 and 24 (g water/g polymer) have been found for the systems with and without spacer respectively. The polymers have been shown to be efficient catalysts for aldol reactions under homogeneous conditions in DMF but not in water. 相似文献
37.
Narender Singh Dr. Alfonso Dueñas‐González Dr. Frank Lyko Dr. Jose L. Medina‐Franco Dr. 《ChemMedChem》2009,4(5):792-799
A series of DNA methyltransferase 1 (DNMT1) inhibitors were modeled by docking and molecular dynamics studies to rationalize their activity. Our findings will be valuable in guiding research efforts toward the rational design and virtual screening of novel DNMT inhibitors.
38.
Urias-Orona V Rascón-Chu A Lizardi-Mendoza J Carvajal-Millán E Gardea AA Ramírez-Wong B 《International journal of molecular sciences》2010,11(10):3686-3695
A novel pectin was acid extracted from chickpea husk (CHP). CHP presented a 67% (w/w) of galacturonic acid, an intrinsic viscosity of 374 mL/g and a viscosimetric molecular weight of 110 kDa. Fourier transform infrared spectroscopy spectrum of CHP indicated a degree of esterification of about 10%. The CHP-calcium system formed ionic gels with a storage (G') modulus of 40 Pa and gel set time (G' > G″) of 3 min at 1% (w/v), and a G' of 131 Pa and gel set time of 1 min at 2% (w/v). The G' of CHP gels was not greatly affected by temperature. The results attained suggest that chickpea husk can be a potential source of a gelling pectin material. 相似文献
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40.
Joana Silva Celso Alves Alice Martins Patrícia Susano Marco Simes Miguel Guedes Stephanie Rehfeldt Susete Pinteus Helena Gaspar Amrico Rodrigues Mrcia Ines Goettert Amparo Alfonso Rui Pedrosa 《International journal of molecular sciences》2021,22(4)
Parkinsons Disease (PD) is the second most common neurodegenerative disease worldwide, and is characterized by a progressive degeneration of dopaminergic neurons. Without an effective treatment, it is crucial to find new therapeutic options to fight the neurodegenerative process, which may arise from marine resources. Accordingly, the goal of the present work was to evaluate the ability of the monoterpenoid lactone Loliolide, isolated from the green seaweed Codium tomentosum, to prevent neurological cell death mediated by the neurotoxin 6-hydroxydopamine (6-OHDA) on SH-SY5Y cells and their anti-inflammatory effects in RAW 264.7 macrophages. Loliolide was obtained from the diethyl ether extract, purified through column chromatography and identified by NMR spectroscopy. The neuroprotective effects were evaluated by the MTT method. Cells’ exposure to 6-OHDA in the presence of Loliolide led to an increase of cells’ viability in 40%, and this effect was mediated by mitochondrial protection, reduction of oxidative stress condition and apoptosis, and inhibition of the NF-kB pathway. Additionally, Loliolide also suppressed nitric oxide production and inhibited the production of TNF-α and IL-6 pro-inflammatory cytokines. The results suggest that Loliolide can inspire the development of new neuroprotective therapeutic agents and thus, more detailed studies should be considered to validate its pharmacological potential. 相似文献