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1.
Artigo em Inglês | MEDLINE | ID: mdl-27420082

RESUMO

Bisphenol A (BPA) is a ubiquitous compound used in polymer manufacturing for a wide array of applications; however, increasing evidence has shown that BPA causes significant endocrine disruption and this has raised public concerns over safety and exposure limits. The use of renewable materials as polymer feedstocks provides an opportunity to develop replacement compounds for BPA that are sustainable and exhibit unique properties due to their diverse structures. As new bio-based materials are developed and tested, it is important to consider the impacts of both monomers and polymers on human health. Molecular docking simulations using the Estrogenic Activity Database in conjunction with the decision forest were performed as part of a two-tier in silico model to predict the activity of 29 bio-based platform chemicals in the estrogen receptor-α (ERα). Fifteen of the candidates were predicted as ER binders and fifteen as non-binders. Gaining insight into the estrogenic activity of the bio-based BPA replacements aids in the sustainable development of new polymeric materials.


Assuntos
Compostos Benzidrílicos/farmacologia , Disruptores Endócrinos/farmacologia , Receptor alfa de Estrogênio/efeitos dos fármacos , Simulação de Acoplamento Molecular , Fenóis/farmacologia , Compostos Benzidrílicos/química , Simulação por Computador , Disruptores Endócrinos/química , Humanos , Fenóis/química
2.
Carbohydr Polym ; 100: 97-106, 2014 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-24188843

RESUMO

In recent years, the development of renewable bio-based resins has gained interest as potential replacements for petroleum based resins. Modified carbohydrate-based derivatives have favorable structural features such as fused bicyclic rings that offer promising candidates for the development of novel renewable polymers with improved thermomechanical properties when compared to early bio-based resins. Isosorbide is one such compound and has been utilized as the stiffness component for the synthesis of novel unsaturated polyesters (UPE) resins. Resin blends of BioUPE systems with styrene were shown to possess viscosities (120-2200 cP) amenable to a variety of liquid molding techniques, and after cure had Tgs (53-107 °C) and storage moduli (430-1650 MPa) that are in the desired range for composite materials. These investigations show that BioUPEs containing isosorbide can be tailored during synthesis of the prepolymer to meet the needs of different property profiles.


Assuntos
Isossorbida/química , Poliésteres/química , Resinas Sintéticas/química , Temperatura , Fenômenos Mecânicos , Solubilidade , Viscosidade
3.
Artigo em Inglês | MEDLINE | ID: mdl-23473101

RESUMO

A series of flexible carbocyclic pyrimidine nucleosides has been designed and synthesized. In contrast to previously reported "fleximers" from our laboratory, these analogues have the connectivity of the heterocyclic base system "reversed", where the pyrimidine ring is attached to the sugar moiety, rather than the five membered imidazole ring. As was previously seen with the ribose fleximers, their inherent flexibility should allow them to adjust to enzyme binding site mutations, as well as increase the affinity for atypical enzymes. Preliminary biological screening has revealed surprising inhibition of adenosine deaminase, despite their lack of resemblance to adenosine.


Assuntos
Inibidores de Adenosina Desaminase/síntese química , Adenosina/análogos & derivados , Nucleosídeos de Pirimidina/síntese química , Adenosina Desaminase/metabolismo , Sítios de Ligação/genética , Nucleosídeos de Pirimidina/química
4.
ChemSusChem ; 5(7): 1291-7, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22517580

RESUMO

Lignin is a copious paper and pulping waste product that has the potential to yield valuable, low molecular weight, single aromatic chemicals when strategically depolymerized. The single aromatic lignin model compounds, vanillin, guaiacol, and eugenol, were methacrylated by esterification with methacrylic anhydride and a catalytic amount of 4-dimethylaminopyridine. Methacrylated guaiacol (MG) and methacrylated eugenol (ME) exhibited low viscosities at room temperature (MG: 17 cP and ME: 28 cP). When used as reactive diluents in vinyl ester resins, they produced resin viscosities higher than that of vinyl ester-styrene blends. The relative volatilities of MG (1.05 wt% loss in 18 h) and ME (0.96 wt% loss in 18 h) measured by means of thermogravimetric analysis (TGA) were considerably lower than that of styrene (93.7 wt% loss in 3 h) indicating the potential of these chemicals to be environmentally friendly reactive diluents. Bulk polymerization of MG and ME generated homopolymers with glass transition temperatures (T(g)s) of 92 and 103 °C, respectively. Blends of a standard vinyl ester resin with MG and ME (50 wt % reactive diluent) produced thermosets with T(g)s of 127 and 153 °C, respectively, which are comparable to vinyl ester-styrene resins, thus demonstrating the ability of MG and ME to completely replace styrene as reactive diluents in liquid molding resins without sacrificing cured-resin thermal performance.


Assuntos
Benzaldeídos/química , Eugenol/química , Guaiacol/química , Resinas Sintéticas/química , Carbono/química , Polimerização , Estireno/química , Temperatura de Transição
5.
Medchemcomm ; 2(7)2011 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-24312722

RESUMO

A series of 5'-nor carbocyclic "reverse" flexible nucleosides or "fleximers" have been designed wherein the nucleobase scaffold resembles a "split" purine as well as a substituted pyrimidine. This modification was employed to explore recognition by both purine and pyrimidine metabolizing enzymes. The synthesis of the carbocyclic fleximers and the results of their preliminary biological screening are described herein.

6.
Bioorg Med Chem ; 17(15): 5520-5, 2009 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-19592260

RESUMO

The blending of key structural features from the purine and pyrimidine nucleobase scaffolds gives rise to a new class of hybrid nucleosides. The purine-pyrimidine hybrid nucleosides can be viewed as either N-3 ribosylated purines or 5,6-disubstituted pyrimidines, thus recognition by both purine- and pyrimidine-metabolizing enzymes is possible. Given the increasing reports of the development of resistance in many enzymatic systems, a drug that could be recognized by more than one enzyme could prove highly advantageous in overcoming resistance mechanisms related to binding site mutations. In that regard, the design, synthesis and results of preliminary biological activity for a series of carbocyclic uracil derivatives with either a fused imidazole or thiazole ring are presented herein.


Assuntos
Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , Nucleosídeos de Purina/química , Nucleosídeos de Purina/farmacologia , Nucleosídeos de Pirimidina/química , Nucleosídeos de Pirimidina/farmacologia , Adenosil-Homocisteinase/antagonistas & inibidores , Adenosil-Homocisteinase/metabolismo , Inibidores Enzimáticos/síntese química , Imidazóis/química , Estrutura Molecular , Nucleosídeos de Purina/síntese química , Nucleosídeos de Pirimidina/síntese química , Tiazóis/química , Uracila/síntese química , Uracila/química , Uracila/farmacologia
7.
Nucleic Acids Symp Ser (Oxf) ; (52): 571-2, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18776508

RESUMO

Nucleosides are ubiquitous in biological systems and as such, have been a focus of medicinal chemistry research in the search for new and potent therapeutic compounds. There are a number of modified nucleosides on the market, however increasing reports of resistance by mutation of either the enzyme binding site or the pathway that they are designed to interrupt are surfacing. As shown in recent reports, a candidate that can change conformation and still maintain recognition by the target enzyme would be highly desirable, and it is for this reason that flexible substrates have recently been sought as potential therapeutics. With this goal in mind, we have begun investigation into novel flexible scaffolds capable of overcoming viral resistance mechanisms resulting from binding site mutations.


Assuntos
Uridina/análogos & derivados , Antivirais/síntese química , Antivirais/química , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/química , Nucleosídeos de Pirimidina/síntese química , Nucleosídeos de Pirimidina/química
8.
Bioorg Med Chem ; 14(23): 7967-71, 2006 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-16904326

RESUMO

The design, synthesis, and unexpected inhibitory activity against S-adenosyl-homocysteine (SAH) hydrolase (SAHase, EC 3.3.1.1) for a series of truncated carbocyclic pyrimidine nucleoside analogues is presented. Of the four nucleosides obtained, 10 was found to be active with a Ki value of 5.0 microM against SAHase.


Assuntos
Adenosil-Homocisteinase/antagonistas & inibidores , Nucleosídeos de Pirimidina/síntese química , Nucleosídeos de Pirimidina/farmacologia , Desenho de Fármacos , Cinética , Relação Estrutura-Atividade
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