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1.
Chem Pharm Bull (Tokyo) ; 72(4): 408-412, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38658365

RESUMEN

A facile and selective ß-D-glucuronidation of alcohols, such as (-)-menthol, cholestanol, (+)- and (-)-borneols, and 2-adamantanol, using commercially available methyl 1,2,3,4-tetra-O-acetyl-ß-D-glucuronate as the glycosyl donor and trimethylsilyl bis(trifluoromethanesulfonyl)imide (Tf2NTMS) (0.5 equivalent) as the activator in 1,4-dioxane at 60 °C gave products in moderate yields. The addition of MS4A increased the ß : α ratios of D-glucuronides when cholestanol, (+)-borneol, and 2-adamantanol were used as the acceptor substrate.


Asunto(s)
Dioxanos , Solventes , Dioxanos/química , Solventes/química , Glucurónidos/química , Glucurónidos/síntesis química , Glicosilación , Estructura Molecular
2.
Acta Biomater ; 180: 183-196, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38604465

RESUMEN

The utilization of biodegradable magnesium (Mg) alloys in the fabrication of temporary non-vascular stents is an innovative trend in biomedical engineering. However, the heterogeneous degradation profiles of these biomaterials, together with potential bacterial colonization that could precipitate infectious or stenotic complications, are critical obstacles precluding their widespread clinical application. In pursuit of overcoming these limitations, this study applies the principles of biomimicry, particularly the hydrophobic and anti-fouling characteristics of lotus leaves, to pioneer the creation of nanocomposite coatings. These coatings integrate poly-trimethylene carbonate (PTMC) with covalent organic frameworks (COFs), to modify the stent's surface property. The strategic design of the coating's topography, porosity, and self-polishing capabilities collectively aims to decelerate degradation processes and minimize biological adhesion. The protective qualities of the coatings were substantiated through rigorous testing in both in vitro dynamic bile tests and in vivo New Zealand rabbit choledochal models. Empirical findings from these trials confirmed that the implementation of COF-based nanocomposite coatings robustly fortifies Mg implantations, conferring heightened resistance to both biocorrosion and biofouling as well as improved biocompatibility within bodily environments. The outcomes of this research elucidate a comprehensive framework for the multifaceted strategies against stent corrosion and fouling, thereby charting a visionary pathway toward the systematic conception of a new class of reliable COF-derived surface modifications poised to amplify the efficacy of Mg-based stents. STATEMENT OF SIGNIFICANCE: Biodegradable magnesium (Mg) alloys are widely utilized in temporary stents, though their rapid degradation and susceptibility to bacterial infection pose significant challenges. Our research has developed a nanocomposite coating inspired by the lotus, integrating poly-trimethylene carbonate with covalent organic frameworks (COF). The coating achieved self-polishing property and optimal surface energy on the Mg substrate, which decelerates stent degradation and reduces biofilm formation. Comprehensive evaluations utilizing dynamic bile simulations and implantation in New Zealand rabbit choledochal models reveal that the coating improves the durability and longevity of the stent. The implications of these findings suggest the potential COF-based Mg alloy stent surface treatments and a leap forward in advancing stent performance and endurance in clinical applications.


Asunto(s)
Implantes Absorbibles , Materiales Biocompatibles Revestidos , Magnesio , Nanocompuestos , Stents , Animales , Conejos , Magnesio/química , Magnesio/farmacología , Nanocompuestos/química , Corrosión , Materiales Biocompatibles Revestidos/química , Materiales Biocompatibles Revestidos/farmacología , Estructuras Metalorgánicas/química , Estructuras Metalorgánicas/farmacología , Incrustaciones Biológicas/prevención & control , Dioxanos/química , Materiales Biomiméticos/química , Materiales Biomiméticos/farmacología , Polímeros/química , Polímeros/farmacología , Aleaciones/química , Aleaciones/farmacología
3.
Molecules ; 28(18)2023 Sep 14.
Artículo en Inglés | MEDLINE | ID: mdl-37764403

RESUMEN

Bioactive amines are highly relevant for clinical and industrial application to ensure the metabolic status of a biological process. Apart from this, generally, amine identification is a key step in various bioorganic processes ranging from protein chemistry to biomaterial fabrication. However, many amines have a negative impact on the environment and the excess intake of amines can have tremendous adverse health effects. Thus, easy, fast, sensitive, and reliable sensing methods for amine identification are strongly searched for. In the past few years, Meldrum's acid furfural conjugate (MAFC) has been extensively explored as a starting material for the synthesis of photoswitchable donor-acceptor Stenhouse adducts (DASA). DASA formation hereby results from the rapid reaction of MAFC with primary and secondary amines, which has so far been demonstrated through numerous publications for different applications. The linear form of the MAFC-based DASA exhibits intense pink coloration due to its linear conjugated triene-2-ol conformation, which has inspired researchers to use this easy synthesizable molecule as an optical sensor for primary, secondary, and biogenic amines. Due to its new entry into amine identification, a collection of the literature exclusively on MAFC is demanded. In this mini review, we intend to present the state-of-the-art of MAFC as an optical molecular sensor in hopes to motivate researchers to find even more applications of MAFC-based sensors and methods that pave the way to their usage in medicinal applications.


Asunto(s)
Aminas Biogénicas , Furaldehído , Dioxanos/química
4.
Chem Asian J ; 18(12): e202300258, 2023 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-37092331

RESUMEN

Latent cyclic carbon-centered nucleophiles (latent C-nucleophiles) are recently proving their value in the field of reaction-based fluorescent probes, far beyond their primary utility in organic synthesis. They are typically used to introduce a Michael acceptor moiety acting as a recognition/reaction site for analyte to be detected or as a kinetic promoter of fluorogenic cascade reactions triggered by a reactive species. C-nucleophiles bearing a further reactive handle offer an additional opportunity for tuning the physicochemical/targeting properties or providing drug-releasing capabilities to these probes, through the covalent attachment of ad hoc chemical moiety. In order to implement such strategy to fluorogenic/chromogenic enzyme substrates based on the "covalent-assembly" principle, we have explored the potential of some functionalized derivatives of barbituric acid, piperidine-2,4-dione and Meldrum's acid. Our investigations based on the rational design and analytical validations of enzyme-responsive caged precursors of fluorescent pyronin dyes and 7-(diethylamino)coumarin-3-carboxylic acid, led to identify a versatile candidate suitable for this late-stage structural optimization approach. This Meldrum's acid derivative enables to either enhance water solubility or achieve the reversible conjugation of a targeting ligand, while promoting in situ formation of fluorophore upon enzymatic activation. This study opens the way to novel multifunctional fluorescence imaging probes and optically modulated small conjugate-based theranostics.


Asunto(s)
Dioxanos , Colorantes Fluorescentes , Dioxanos/química , Sitios de Unión
5.
ACS Biomater Sci Eng ; 9(1): 520-530, 2023 01 09.
Artículo en Inglés | MEDLINE | ID: mdl-36459430

RESUMEN

Smart materials have great potential in many biomedical applications, in which biodegradable shape memory polymers (SMPs) can be used as surgical sutures, implants, and stents. Poly(dl-lactide-co-trimethylene carbonate) (PDLLTC) represents one of the promising SMPs and is widely used in biomedical applications. However, the relationship between its shape memory property and chemical structure has not been fully studied and needs further elaboration. In this work, PDLLTC copolymers in different compositions have been synthesized, and their shape memory properties have been investigated. It has been found that the shape memory property is related to the chemical composition and polymeric chain segments. The copolymer with a DLLA/TMC ratio of 75:25 (PDLLTC7525) has been demonstrated with great shape fixation and recovery ratio at human body temperature. Furthermore, PDLLTC7525-based self-morphing small-diameter vascular scaffolds adhered with inner electrospun aligned gelatin/hyaluronic acid (Gel/HA) nanofibers have been constructed, as a merit of its shape memory property. The scaffolds have been demonstrated to facilitate the proliferation and adhesion of endothelial cells on the inner layer. Therefore, PDLLTC with tailorable shape memory properties represents a promising candidate for the development of SMPs, as well as for small-diameter vascular scaffolds construction.


Asunto(s)
Células Endoteliales , Polímeros , Humanos , Polímeros/química , Dioxanos/química
6.
Int J Mol Sci ; 23(24)2022 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-36555639

RESUMEN

The Michael addition reaction between dithiomalondianilide (N,N'-diphenyldithiomalondiamide) and arylmethylidene Meldrum's acids, accompanied by subsequent heterocyclization, was investigated along with factors affecting the mixture composition of the obtained products. The plausible mechanism includes the formation of stable Michael adducts which, under the studied conditions, undergo further transformations to yield corresponding N-methylmorpholinium 4-aryl-6-oxo-3-(N-phenylthio-carbamoyl)-1,4,5,6-tetrahydropyridin-2-thiolates and their oxidation derivatives, 4,5-dihydro-3H-[1,2]dithiolo[3,4-b]pyridin-6(7H)-ones. The structure of one such product, N-methylmorpholinium 2,2-dimethyl-5-(1-(2-nitrophenyl)-3-(phenylamino)-2-(N-phenylthiocarbamoyl)-3-thioxopropyl)-4-oxo-4H-1,3-dioxin-6-olate, was confirmed via X-ray crystallography.


Asunto(s)
Dioxanos , Oxidación-Reducción , Dioxanos/química
7.
Environ Sci Process Impacts ; 24(8): 1165-1172, 2022 Aug 17.
Artículo en Inglés | MEDLINE | ID: mdl-35796164

RESUMEN

In situ chemical oxidation (ISCO) has become a widely used soil and groundwater remediation method. Oxidative-attenuation tracers can be used to provide real-time, explicit delineation of contaminant mass-transfer and transformation behavior during an ISCO remediation project. The objective of this study was to evaluate the potential of employing sucralose, a widely used artificial sweetener, as an oxidative-attenuation tracer to characterize the remediation efficiency of 1,4-dioxane (dioxane) by persulfate-based ISCO. Batch and miscible-displacement experiments were conducted to examine the degradation rate and transport behavior of sucralose compared to that of dioxane. Comparable magnitudes and rates of degradation were observed for sucralose and dioxane in batch-reactor experiments with soil and persulfate. The breakthrough curves of sucralose and dioxane transport in a soil-packed column were coincident. The retardation factors were 1.1 for both compounds, indicating limited sorption for both sucralose and dioxane by the soil. Limited degradation was observed in the miscible-displacement experiments, consistent with the short residence time compared to the half-lives of sucralose and dioxane. Persulfate transport and decomposition behavior in the soil-packed columns was similar in the presence of sucralose or dioxane. A simulated tracer test was conducted to illustrate the application of sucralose as an oxidative-attenuation tracer at the pilot scale. These results demonstrate the potential of sucralose as an oxidative-attenuation tracer to support the robust design of ISCO applications for dioxane. The oxidative-attenuation tracer test method is anticipated to be an effective approach for characterizing mass-removal behavior of other emerging contaminants with appropriate selection of tracer.


Asunto(s)
Agua Subterránea , Contaminantes Químicos del Agua , Dioxanos/química , Agua Subterránea/química , Oxidación-Reducción , Estrés Oxidativo , Suelo/química , Sacarosa/análogos & derivados , Contaminantes Químicos del Agua/análisis
8.
ChemSusChem ; 15(18): e202201075, 2022 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-35803895

RESUMEN

In this study, the synthesis of two new guanidine hydroquinoline ligands served as basis for six new zinc guanidine complexes. Two of these complexes showed very high activity in the lactide polymerization under industrial conditions. The lactide polymerization was demonstrated in solution and melt conditions observing high activity and molar masses up to 90 000 g mol-1 . Density functional theory studies elucidated the high activity of the complexes associated with the influence of the ligand backbone and the use of triflate counterions. On the way towards a circular economy, polymerization and depolymerization go hand in hand. So far, guanidine complexes have only shown their good activity in the ring opening polymerization of esters, and guanidine complexes with pure N donors have not been tested in recycling processes. Herein, the excellent ability of zinc guanidine complexes to catalyze both polymerization and depolymerization was demonstrated. The two most promising zinc complexes efficiently mediated the methanolysis of polylactide into methyl lactate under mild reaction conditions.


Asunto(s)
Complejos de Coordinación , Zinc , Complejos de Coordinación/química , Cristalografía por Rayos X , Dioxanos/química , Guanidina , Guanidinas , Ligandos , Polimerizacion , Zinc/química
9.
Angew Chem Int Ed Engl ; 61(33): e202204531, 2022 08 15.
Artículo en Inglés | MEDLINE | ID: mdl-35582840

RESUMEN

Chemical recycling of poly(L-lactic acid) to the cyclic monomer L-lactide is hampered by low selectivity and by epimerization and elimination reactions, impeding its use on a large scale. The high number of side reactions originates from the high ceiling temperature (Tc ) of L-lactide, which necessitates high temperatures or multistep reactions to achieve recycling to L-lactide. To circumvent this issue, we utilized the impact of solvent interactions on the monomer-polymer equilibrium to decrease the Tc of L-lactide. Analyzing the observed Tc in different solvents in relation to their Hildebrand solubility parameter revealed a "like recycles like" relationship. The decreased Tc , obtained by selecting solvents that interact strongly with the monomer (dimethyl formamide or the green solvent γ-valerolactone), allowed chemical recycling of high-molecular-weight poly(L-lactic acid) directly to L-lactide, within 1-4 h at 140 °C, with >95 % conversion and 98-99 % selectivity. Recycled L-lactide was isolated and repolymerized with high control over molecular weight and dispersity, closing the polymer loop.


Asunto(s)
Dioxanos , Poliésteres , Dioxanos/química , Poliésteres/química , Polímeros/química , Solventes
10.
Angew Chem Int Ed Engl ; 61(20): e202202660, 2022 05 09.
Artículo en Inglés | MEDLINE | ID: mdl-35254726

RESUMEN

Electrochemical redox-control is an emerging strategy for the regulation of polymerization process without the addition of external oxidants and reductants, which enables the control over composition, microstructure and properties of the polymer products. In this paper, based on the chemical selectivity of heterometallic Salen-Co-Mn complexes of different valences, an electrochemically switchable strategy was developed for the copolymerization of lactide (LA), CO2 and epoxides. The switchable redox reactions endowed this system with the capability to easily synthesize a multi-block copolymer of polylactide (PLA) and polycarbonate (PC). Moreover, the multi-block copolymer could be further modified by introducing various monomers with different microstructures and functional groups.


Asunto(s)
Dióxido de Carbono , Compuestos Epoxi , Dióxido de Carbono/química , Dioxanos/química , Compuestos Epoxi/química , Polimerizacion , Polímeros/química
11.
Molecules ; 27(3)2022 Feb 08.
Artículo en Inglés | MEDLINE | ID: mdl-35164403

RESUMEN

Aliphatic polyesters are the most common type of biodegradable synthetic polymer used in many pharmaceutical applications nowadays. This report describes the ring-opening polymerization (ROP) of l-lactide (L-LA), ε-caprolactone (CL) and glycolide (Gly) in the presence of a simple, inexpensive and convenient PEG200-BiOct3 catalytic system. The chemical structures of the obtained copolymers were characterized by 1H- or 13C-NMR. GPC was used to estimate the average molecular weight of the resulting polyesters, whereas TGA and DSC were employed to determine the thermal properties of polymeric products. The effects of temperature, reaction time, and catalyst content on the polymerization process were investigated. Importantly, the obtained polyesters were not cyto- or genotoxic, which is significant in terms of the potential for medical applications (e.g., for drug delivery systems). As a result of transesterification, the copolymers obtained had a random distribution of comonomer units along the polymer chain. The thermal analysis indicated an amorphous nature of poly(l-lactide-co-ε-caprolactone) (PLACL) and a low degree of crystallinity of poly(ε-caprolactone-co-glycolide) (PCLGA, Xc = 15.1%), in accordance with the microstructures with random distributions and short sequences of comonomer units (l = 1.02-2.82). Significant differences in reactivity were observed among comonomers, confirming preferential ring opening of L-LA during the copolymerization process.


Asunto(s)
Bismuto/química , Caproatos/química , Dioxanos/química , Lactonas/química , Ácido Poliglicólico/química , Polimerizacion , Caproatos/síntesis química , Catálisis , Dioxanos/síntesis química , Lactonas/síntesis química , Poliésteres/síntesis química , Poliésteres/química , Ácido Poliglicólico/síntesis química , Temperatura
12.
Dalton Trans ; 51(5): 2083-2093, 2022 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-35048912

RESUMEN

Herein, an amine decorated Cd(II) metal-organic framework (MOF) with a uninodal 6-c topology was synthesized as a suitable platform for facile post-synthetic modification (PSM). The as-synthesized parent d10-MOF (1) with free -NH2 centers, when functionalized with two different carbonyl substituents (1-naphthaldehyde and benzophenone) of varying conjugation, produces two novel luminescent MOFs (LMOFs) viz.PSM-1 and PSM-2. The judicious incorporation of carbonyl substituents into the skeleton of 1 was rationalized via ESI-MS, 1H-NMR, FT-IR and PXRD analyses. Interestingly, both PSM-1 and PSM-2 show 'turn-on' luminescent behaviour in the presence of 1,4-dioxane with the limit of detection (LOD) as 1.079 ppm and 2.487 ppm, respectively, with prompt response time (∼55 s & ∼58 s, respectively). The inhibition of PET is comprehended to be the prime reason for luminescence enhancement upon interaction with the targeted analyte which was further validated from DFT calculations. In continuation, the PSM-MOFs were equally responsive towards 1,4-dioxane in several complex environmental matrices and cosmetic products. Additionally, vapor phase detection of 1,4-dioxane using PSM-MOFs has also been demonstrated as an additional advantage ensuring propagation of future research endeavour.


Asunto(s)
Dioxanos/química , Dioxanos/aislamiento & purificación , Gases/química , Compuestos Organometálicos/química , Agua/química , Aminas , Cadmio/química , Dioxanos/toxicidad , Contaminantes Ambientales/química , Modelos Moleculares , Estructura Molecular
13.
Mol Divers ; 26(2): 1141-1150, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-34129183

RESUMEN

The [3 + 2]-cycloaddition reaction of nitrile imines with 2,2-dimethyl-5-[(4-oxo-4H-chromen-3-yl)methylene]-1,3-dioxane-4,6-dione tends to form the reverse-orientation products under ultrasound irradiation in EtOH in the presence of Et3N. Evidence for the structure of product 5b was obtained from single-crystal X-ray analysis.


Asunto(s)
Iminas , Nitrilos , Cromonas , Reacción de Cicloadición , Dioxanos/química , Iminas/química
14.
Eur J Med Chem ; 227: 113950, 2022 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-34731761

RESUMEN

Ergosterol exert the important function in maintaining the fluidity and osmotic pressure of fungal cells, and its key biosynthesis enzymes (Squalene epoxidase, SE; 14 α-demethylase, CYP51) displayed the obvious synergistic effects. Therefore, we expected to discover the novel antifungal compounds with dual-target (SE/CYP51) inhibitory activity. In the progress, we screened the different kinds of potent fragments based on the dual-target (CYP51, SE) features, and the method of fragment-based drug discovery (FBDD) was used to guide the construction of three different series of benzodioxane compounds. Subsequently, their chemical structures were synthesized and evaluated. These compounds displayed the obvious biological activity against the pathogenic fungal strains. Notably, target compounds 10a-2 and 22a-2 possessed the excellent broad-spectrum anti-fungal activity (MIC50, 0.125-2.0 µg/mL) and the activity against drug-resistant strains (MIC50, 0.5-2.0 µg/mL). Preliminary mechanism studies have confirmed that these compounds effectively inhibited the dual-target (SE/CYP51) activity, they could cause fungal rupture and death by blocking the bio-synthetic pathway of ergosterol. Further experiments discovered that compounds 10a-2 and 22a-2 also maintained a certain of anti-fungal effect in vivo. In summary, this study not only provided the new dual-target drug design strategy and method, but also discover the potential antifungal compounds.


Asunto(s)
Inhibidores de 14 alfa Desmetilasa/farmacología , Antifúngicos/farmacología , Derivados del Benceno/farmacología , Candida/efectos de los fármacos , Dioxanos/farmacología , Esterol 14-Desmetilasa/metabolismo , Inhibidores de 14 alfa Desmetilasa/síntesis química , Inhibidores de 14 alfa Desmetilasa/química , Antifúngicos/síntesis química , Antifúngicos/química , Derivados del Benceno/síntesis química , Derivados del Benceno/química , Candida/metabolismo , Dioxanos/síntesis química , Dioxanos/química , Relación Dosis-Respuesta a Droga , Pruebas de Sensibilidad Microbiana , Modelos Moleculares , Estructura Molecular , Relación Estructura-Actividad
15.
Acta Crystallogr C Struct Chem ; 77(Pt 11): 698-706, 2021 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-34738540

RESUMEN

Four new solvates of the anti-HIV compound etravirine [systematic name: 4-({6-amino-5-bromo-2-[(4-cyanophenyl)amino]pyrimidin-4-yl}oxy)-3,5-dimethylbenzonitrile, C20H15BrN6O] with dimethyl sulfoxide (C2H6OS, two distinct monosolvates), 1,4-dioxane (C4H8O2, the 0.75-solvate) and N,N-dimethylacetamide (C4H9NO, the monosolvate), which exhibit conversion to the same anhydrous etravirine phase upon desolvation, and a stable etravirinium oxalate salt {6-amino-5-bromo-4-(4-cyano-2,6-dimethylphenoxy)-2-[(4-cyanophenyl)amino]pyrimidin-1-ium hemioxalate, C20H16BrN6O+·0.5C2O42-} were obtained. The crystal structures were solved by single-crystal X-ray diffraction and analyzed by powder X-ray diffraction, and the intermolecular interactions were explored by Hirshfeld surface analysis. Lattice energies were evaluated using the atom-atom force field Coulomb-London-Pauli (AA CLP) approximation, which distributes the total energy as four separate contributions: Coulombic, polarization, dispersion and repulsion. The formation of the solvates and the oxalate salt was further characterized by thermal analysis and IR spectroscopy.


Asunto(s)
Fármacos Anti-VIH/química , Nitrilos/química , Pirimidinas/química , Acetamidas/química , Cristalografía por Rayos X , Dimetilsulfóxido/química , Dioxanos/química , Estabilidad de Medicamentos , Estructura Molecular , Oxalatos/química , Sales (Química)/química , Solventes/química
16.
J Med Chem ; 64(20): 15214-15249, 2021 10 28.
Artículo en Inglés | MEDLINE | ID: mdl-34614347

RESUMEN

Novel bacterial topoisomerase inhibitors (NBTIs) are among the most promising new antibiotics in preclinical/clinical development. We previously reported dioxane-linked NBTIs with potent antistaphylococcal activity and reduced hERG inhibition, a key safety liability. Herein, polarity-focused optimization enabled the delineation of clear structure-property relationships for both microsomal metabolic stability and hERG inhibition, resulting in the identification of lead compound 79. This molecule demonstrates potent antibacterial activity against diverse Gram-positive pathogens, inhibition of both DNA gyrase and topoisomerase IV, a low frequency of resistance, a favorable in vitro cardiovascular safety profile, and in vivo efficacy in a murine model of methicillin-resistant Staphylococcus aureus infection.


Asunto(s)
Antibacterianos/farmacología , Dioxanos/farmacología , Inhibidores Enzimáticos/farmacología , Canales de Potasio Éter-A-Go-Go/antagonistas & inhibidores , Staphylococcus aureus Resistente a Meticilina/efectos de los fármacos , Antibacterianos/síntesis química , Antibacterianos/química , Girasa de ADN/metabolismo , Topoisomerasa de ADN IV/antagonistas & inhibidores , Topoisomerasa de ADN IV/metabolismo , Dioxanos/síntesis química , Dioxanos/química , Relación Dosis-Respuesta a Droga , Inhibidores Enzimáticos/síntesis química , Inhibidores Enzimáticos/química , Canales de Potasio Éter-A-Go-Go/metabolismo , Humanos , Pruebas de Sensibilidad Microbiana , Estructura Molecular , Relación Estructura-Actividad
17.
Int J Biol Macromol ; 193(Pt A): 414-424, 2021 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-34715200

RESUMEN

The paper presents the synthesis and characterization of poly(trimethylene carbonate) grafted chitosan as a new water soluble biopolymer suitable for in vivo applications. The synthesis was performed via ring-opening polymerization of 1,3-dioxan-2-one (trimethylene carbonate) (TMC) monomer, initiated by the functional groups of chitosan in the presence of toluene as solvent/swelling agent. By varying the molar ratio between the glucosamine units of chitosan and TMC, a series of chitosan derivatives with different content of poly(trimethylene carbonate) chains was synthetized. The structural characterization of the polymers was realized by FTIR and 1H NMR spectroscopy and their solubility was assessed in water and in organic solvents as well. The biocompatibility was investigated by MTS assay on Normal Human Dermal Fibroblasts, and the biodegradability was evaluated in lysozyme buffer solution. Further, the surface properties of the polymer films were analyzed by polarized optical microscopy, atomic force microscopy and water-to-air contact angle measurements. It was established that, by 5% substitution of chitosan with poly(trimethylene carbonate) chains having an average polymerization degree of 7, a water soluble polymer can be attained. Compared to the pristine chitosan, it has improved biocompatibility in solution and moderate wettability and higher biodegradability rate in solid state, pointing its suitability for in vivo applications.


Asunto(s)
Materiales Biocompatibles/química , Quitosano/química , Dioxanos/química , Polímeros/química , Línea Celular , Fibroblastos , Humanos , Propiedades de Superficie , Humectabilidad
18.
Bioorg Chem ; 116: 105333, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34537516

RESUMEN

Natural products--polyoxygenated cyclohexenes exhibited potent anti-tumor activity, such as zeylenone, which is a natural product isolated from Uvaria grandiflora Roxb. This article will attempt to establish a gram-scale synthesis method of (+)-zeylenone and explain the structure-activity relationship of this kind of compound. Total synthesis of (+)-zeylenone was completed in 13 steps with quinic acid as the starting material in 9.8% overall yield. The highlight of the route was the control of the three carbon's chirality by single step dihydroxylation. In addition, different kinds of derivatives were designed and synthesized. Cell Counting Kit-8 (CCK8) assay was used for evaluating antitumor activity against three human cancer cell lines. The structure--activity relationship suggested that compounds with both absolute configurations exhibited tumor-suppressive effects. Moreover, hydroxyls at the C-1/C-2 position were crucial to the activity, and the esterification of large groups at C-1 hydroxyl eliminated the activity. Hydroxyl at the C-3 position was also important as proper ester substituent could increase the potency.


Asunto(s)
Antineoplásicos Fitogénicos/farmacología , Ciclohexanos/farmacología , Dioxanos/farmacología , Uvaria/química , Animales , Antineoplásicos Fitogénicos/química , Antineoplásicos Fitogénicos/aislamiento & purificación , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Ciclohexanos/química , Ciclohexanos/aislamiento & purificación , Dioxanos/química , Dioxanos/aislamiento & purificación , Relación Dosis-Respuesta a Droga , Ensayos de Selección de Medicamentos Antitumorales , Humanos , Ratones , Estructura Molecular , Estereoisomerismo , Relación Estructura-Actividad , Células Tumorales Cultivadas
19.
ACS Appl Mater Interfaces ; 13(33): 38969-38978, 2021 Aug 25.
Artículo en Inglés | MEDLINE | ID: mdl-34399054

RESUMEN

Controlling the microstructure of materials by means of phase separation is a versatile tool for optimizing material properties. Phase separation has been exploited to fabricate intricate microstructures in many fields including cell biology, tissue engineering, optics, and electronics. The aim of this study was to use phase separation to tailor the spatial location of drugs and thereby generate release profiles of drug payload over periods ranging from 1 week to months by exploiting different mechanisms: polymer degradation, polymer diluent dissolution, and control of microstructure. To achieve this, we used drop-on-demand inkjet three-dimensional (3D) printing. We predicted the microstructure resulting from phase separation using high-throughput screening combined with a model based on the Flory-Huggins interaction parameter and were able to show that drug release from 3D-printed objects can be predicted from observations based on single drops of mixtures. We demonstrated for the first time that inkjet 3D printing yields controllable phase separation using picoliter droplets of blended photoreactive oligomers/monomers. This new understanding gives us hierarchical compositional control, from droplet to device, allowing release to be "dialled up" without manipulation of device geometry. We exemplify this approach by fabricating a biodegradable, long-term, multiactive drug delivery subdermal implant ("polyimplant") for combination therapy and personalized treatment of coronary heart disease. This is an important advance for implants that need to be delivered by cannula, where the shape is highly constrained and thus the usual geometrical freedoms associated with 3D printing cannot be easily exploited, which brings a hitherto unseen level of understanding to emergent material properties of 3D printing.


Asunto(s)
Antihipertensivos/química , Enfermedad Coronaria/tratamiento farmacológico , Portadores de Fármacos/química , Excipientes/química , Indoles/química , Polímeros/química , Antihipertensivos/farmacología , Dioxanos/química , Composición de Medicamentos , Liberación de Fármacos , Humanos , Indoles/farmacología , Metacrilatos/química , Transición de Fase , Poliésteres/química , Impresión Tridimensional , Pirrolidinonas/química , Relación Estructura-Actividad
20.
Int J Mol Sci ; 22(14)2021 Jul 13.
Artículo en Inglés | MEDLINE | ID: mdl-34299106

RESUMEN

Atherosclerosis involves an ongoing inflammatory response of the vascular endothelium and vessel wall of the aorta and vein. The pleiotropic effects of statins have been well described in many in vitro and in vivo studies, but these effects are difficult to achieve in clinical practice due to the low bioavailability of statins and their first-pass metabolism in the liver. The aim of this study was to test a vessel wall local drug delivery system (DDS) using PLA microstructures loaded with simvastatin. Wistar rats were fed high cholesterol chow as a model. The rat vessels were chemically injured by repeated injections of perivascular paclitaxel and 5-fluorouracil. The vessels were then cultured and treated by the injection of several concentrations of poly(L,L-lactide) microparticles loaded with the high local HMG-CoA inhibitor simvastatin (0.58 mg/kg) concentration (SVPLA). Histopathological examinations of the harvested vessels and vital organs after 24 h, 7 days and 4 weeks were performed. Microcirculation in mice as an additional test was performed to demonstrate the safety of this approach. A single dose of SVPLA microspheres with an average diameter of 6.4 µm and a drug concentration equal to 8.1% of particles limited the inflammatory reaction of the endothelium and vessel wall and had no influence on microcirculation in vivo or in vitro. A potent pleiotropic (anti-inflammatory) effect of simvastatin after local SVPLA administration was observed. Moreover, significant concentrations of free simvastatin were observed in the vessel wall (compared to the maximum serum level). In addition, it appeared that simvastatin, once locally administered as SVPLA particles, exerted potent pleiotropic effects on chemically injured vessels and presented anti-inflammatory action. Presumably, this effect was due to the high local concentrations of simvastatin. No local or systemic side effects were observed. This approach could be useful for local simvastatin DDSs when high, local drug concentrations are difficult to obtain, or systemic side effects are present.


Asunto(s)
Antiinflamatorios/farmacología , Anticolesterolemiantes/farmacología , Dioxanos/química , Sistemas de Liberación de Medicamentos , Inflamación/tratamiento farmacológico , Simvastatina/farmacología , Animales , Antiinflamatorios/química , Anticolesterolemiantes/administración & dosificación , Ratones , Ratones Endogámicos BALB C , Microesferas , Ratas , Ratas Wistar , Simvastatina/administración & dosificación
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