Synthesis Of New Monomers Research Articles

Polyamine-Functionalized 2'-Amino-LNA in Oligonucleotides: Facile Synthesis of New Monomers and High-Affinity Binding towards ssDNA and dsDNA.

Attachment of cationic moieties to oligonucleotides (ONs) promises not only to increase the binding affinity of antisense ONs by reducing charge repulsion between the two negatively charged strands of a duplex, but also to augment their in vivo stability against nucleases. In this study, polyamine functionality was introduced into ONs by means of 2'-amino-LNA scaffolds. The resulting ONs exhibited efficient binding towards ssDNA, ssRNA and dsDNA targets, and the 2'-amino-LNA analogue carrying a triaminated linker showed the most pronounced duplex- and triplex-stabilizing effect. Molecular modelling revealed that favourable conformational and electrostatic effects led to salt-bridge formation between positively charged polyamine moieties and the Watson-Hoogsteen groove of the dsDNA targets, resulting in the observed triplex stabilization. All the investigated monomers showed increased resistance against 3'-nucleolytic digestion relative to the non-functionalized controls.

Validating a Predictive Structure-Property Relationship by Discovery of Novel Polymers which Reduce Bacterial Biofilm Formation.

Synthetic materials are an everyday component of modern healthcare yet often fail routinely as a consequence of medical-device-centered infections. The incidence rate for catheter-associated urinary tract infections is between 3% and 7% for each day of use, which means that infection is inevitable when resident for sufficient time. The O'Neill Review on antimicrobial resistance estimates that, left unchecked, ten million people will die annually from drug-resistant infections by 2050. Development of biomaterials resistant to bacterial colonization can play an important role in reducing device-associated infections. However, rational design of new biomaterials is hindered by the lack of quantitative structure-activity relationships (QSARs). Here, the development of a predictive QSAR is reported for bacterial biofilm formation on a range of polymers, using calculated molecular descriptors of monomer units to discover and exemplify novel, biofilm-resistant (meth-)acrylate-based polymers. These predictions are validated successfully by the synthesis of new monomers which are polymerized to create coatings found to be resistant to biofilm formation by six different bacterial pathogens: Pseudomonas aeruginosa, Proteus mirabilis, Enterococcus faecalis, Klebsiella pneumoniae, Escherichia coli, and Staphylococcus aureus.

Recent Trends on Transparent Colorless Polyimides with Balanced Thermal and Optical Properties: Design and Synthesis

AbstractRecently, colorless and transparent plastic substrates with high glass transition temperature and suitable thermo‐mechanical properties are in high demand in optoelectronic device industries, due to their various optical applications. Colorless polyimides (CPIs) exhibit both high thermo‐mechanical stability as well as high transparency that are suitable for optoelectronic applications. The most recent (2010–2018) developments on CPIs, in terms of design and synthesis of new monomers and their effects on the thermo‐optical properties of the obtained CPIs, are reviewed in this article.

Polyethersulfones with Improved Thermophysical Properties

New halogen-containing condensation monomers are synthesized via high-temperature polycondensation, on the basis of which, and with the use of 4,4'-dichlorodiphenyl sulfone, new polyethersulfones containing dichloroethylene groups in the main chain are obtained. The characteristic features are studied, and the optimum conditions for the synthesis of new monomers and polyethersulfones are determined. It is shown using state-of-the-art study methods that the new polyethersulfones are superior to industrial polysulfones with respect to their main physicochemical and operational properties. The synthesized polyethersulfones which contain dichloroethylene groups in the main chain are capable of forming cross-linked structures during thermal treatment. Here, the heat, thermal, and hydrolytic resistances of the polymers substantially increase.

Research Progress of Low Dielectric Benzoxazine Resin

Benzoxazine resin, a new type of phenolic resin, has many advantages, such as a strong molecular design, no small molecular release in the curing process, excellent thermal stability and mechanical properties, and a high residual carbon ratio. Thus, it is important for electronic communication industry matrix material. To meet the needs of high-frequency and high-speed communication technology for low-dielectric polymer resin, the low-dielectric modification of benzoxazine resin is of great significance to the high frequency and high-speed propagation of the signal, which attracts a wide range of materials researchers’ attention. In this paper, we review a series of studies on the low dielectric modification of benzoxazine resin in recent years, including the synthesis of new monomers, inorganic - organic hybridization, copolymerization with other resins, and low molecular weight benzoxazine resin research trends.

Synthesis and characterization of Dopamine graft compound N-methacryloyl 3,4-dihydroxyl-phenylamine

In order to obtain adhesive biomaterials inspired by mussels, the intermediate derivatives of dopamine, N-methacryloyl 3,4-dihydroxyl-phenylamine (dopamine methacryla-mide DMA), was synthesized by grafting methacrylate anhydride to dopamine. The structure of the compound was confirmed by fourier transform infrared spectroscopy and nuclear magnetic resonance. The thermal stability of DMA was also characterized by thermo gravimetric analysis and differential scanning calorimeters techniques. The surface morphology of DMA crystal was analysed by scanning electron microscope analyses. The present result showed that the synthesis of new monomers was successfully fulfilled and the new compounds retain the hydroxyl functional groups. The surface morphologies and thermal stability of DMA crystal were also altered by grafting reaction.

Nβ-Fmoc-Nβ-Methyl-aza-β³-amino Acids

The potential of peptides as drug candidates is limited by theirpoor pharmacokinetic properties. Many peptides have a short half-life,in vivo half-life, and insufficient oral availability. Inspired bythe N-methylation of peptides as a promising way to rationally improvekey pharmacokinetic characteristics, we report our efforts towardan easy synthesis of new monomers N β -Fmoc- N β -Me-aza-β 3 -aminoacids. These synthetic building blocks will be useful for solid-phasesynthesis of new peptidomimetics.

Synthesis of new monomers, cyanomethylnorbornyl acrylates

The [4+2]-cycloaddition of cyclopentadiene to methacrylonitrile and addition of acrylic acids to the resulting exo-2-cyano-endo-2-methylnorborn-5-ene were studied. The possibility was explored of synthesizing cyano-containing bicyclic acrylates suitable as reactive monomers for preparation of polymeric products.

Towards poly(ester) nanoparticles: recent advances in the synthesis of functional poly(ester)s by ring-opening polymerization

The recent trends in the synthesis of functional poly(ester)s by ring-opening polymerization (ROP) are reviewed. While the use of ROP processes for the synthesis of poly(lactide), poly(lactide-co-glycolide) and several poly(lactone)s has been well studied, the paucity of functional groups available for further reaction limits their application. Recent efforts to expand this available functionality are reviewed focusing on the application of renewable resources in the synthesis of new monomers and the utilization of click chemistry to provide common intermediate polymers in the manipulation of poly(ester) functionality. In turn these advances are leading to a new generation of precisely controlled nanoparticles comprised entirely of poly(ester)s.

Synthesis of new monomer 3,3′-diamino-4,4′-bis{p-[(diethoxyphosphoryl)methyl]phenylamino}diphenyl sulfone and polybenzimidazoles on its basis

Synthesis of new monomer 3,3′-diamino-4,4′-bis{p-[(diethoxyphosphoryl)methyl]phenylamino}diphenyl sulfone and polybenzimidazoles on its basis

The Discovery of Metallocene- and Metallocene-Like Addition Polymers

A personal account is given of the “early days” in the development of metallocene addition polymers in order to mark the 50th anniversary of the first report of a metallocene addition polymer, poly(vinylferrocene), by Arimoto and Haven at DuPont Inc. in 1955. Sometimes looking back, it seems like the early work was quaint and even obvious by today’s standards. However, this was not the case in the 1960s and ‘70s. These polymers seemed a strange departure from the “classic” world of polystyrene, polyacrylates, polyvinyl acetate, polyvinyl chloride, polybutadiene etc. The Polymer Handbook gave us no clue about how vinyl metallocenes might behave. Only through the (then) tedious synthesis of new monomers and a careful study of their homopolymerization kinetics and mechanism, their copolymerization reactivities and the characterization of the contributions the metal makes to their properties, was the stage set for the wider inclusion of organometallic addition polymers into mainstream macromolecular and materials science. Starting in the 1990s, and continuing today, an explosive growth of metal-containing macromolecular science and its extension to materials science has occurred. Herein, the early work in our laboratory is revisited. In the 1960s, metallocenes and organometal carbonyl compounds were a new exotic thrust of chemistry, merging inorganic and organic disciplines. However, few chemists had any thoughts of adapting this young field to polymers and materials. This is easily forgotten now, when practically every issue of numerous journals are filled with articles about polymers, films, multilayered devices etc. containing organic and inorganic hybrid substances (including metals) prepared by designer synthetic chemistry, self-assembly or biologically inspired routes. We have certainly come a long way!

Synthesis and potential radical copolymerization of new monomers based on diallylguanidine

AbstractMethods were elaborated for the synthesis of new monomers, derivatives of diallylguanidine. These monomer salts (acetate and trifluoroacetates) have the ability to polymerize in water and organic solvents in the presence of radical initiators. Radical copolymerization of diallylguanidine and diallyldimethylammonium chloride was investigated. High biocide ability of obtained copolymers was demonstrated. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 91: 439–444, 2004

Investigation on the synthesis and reaction of new aniline derivatives in Pd-catalyzed cross-coupling

New aniline derivatives have been synthesized to investigate the possibility of polymer synthesis by Pd-catalyzed cross-coupling. Dialkylation and ethynylation of the aniline monomers and the synthesis of new monomers 2, 3, and a 2,2′-bipyridine-containing oligomer 4 could be realized.

Polymer Properties on Resins composed of UDMA and Methacrylates with the Carboxyl Group.

The properties of dental matrix resins have been improved by synthesis of new monomers. However, except for improvements in water-resistance, monomers with better mechanical properties than Bis-GMA and UDMA could not being synthesized. Changing the point of emphasis, we tried to improve the mechanical properties controlling the matrix resin higher structure using noncovalent bonds. We prepared a matrix resin structured by UDMA, which is a high viscosity base monomer with imino groups, and by a low viscosity acidic monomer with carboxyl groups, which permits noncovalent bonds such as hydrogen bonds or electrostatic interaction with imino groups. The maximal mechanical strength for matrix resins structured by UDMA and an acidic monomer was obtained with a composition of imino groups and carboxyl groups at a ratio of 1:1. This mechanical strength value was higher than those obtained with UDMA resin or with a Bis-GMA/TEGDMA/UDMA resin with typical composition. The improvement in mechanical properties may be due to the complex based on noncovalent bonds, between the imino groups of UDMA and the carboxyl groups of the acidic monomers.

Funktionalisierte Kammpolymere: Synthesen, modifizierung und anwendungen

AbstractThe present paper deals with the synthesis and modification of functionalized polymers characterized by a special molecular architecture. The reactivity of a functionalized polymer with comb‐like structure can be controlled in a significant manner by the crystalline order of the side chains. In contrast, photocrosslinking of comblike polymers containing cinnamic components in the side chains influences the crystallization process. The air drying process of a modified polybutadiene system with comb‐like structure was shown to depend sensitively on the side chain order. Enzymatic synthesis of new monomers and polymers is briefly reviewed. The complexing capability of cyclodextrines were used to synthesize polyrotaxanes. Finally, the synthesis of a chiral polymerizable dendrimer containing eight estergroups in the monomer unit is presented.

Macromolecular design of new cationic polyelectrolytes

Methods were elaborated for the synthesis of new monomers, derivatives of diallylguanidine and macromers, which contain fragments of polytetrahydrofuran and diallylic nitrogencontaining end groups (diallylamine, alkyldiallylammonium, diallylguanidine both in base and acetate forms). Alkylation of a macromer with a diallylamine end group was carried out with methyl iodide in various organic solvents. The possibility of synthesis of diallylguanidine acetate homopolymer as well as its statistical copolymer with diallyldimethylammonium chloride was shown. For the first time, block copolymers based on synthesized macromers were obtained.

Nucleophilic substitution reactions of 1,4‐dichlorobenzene chromium tricarbonyl with mono‐ and diphenoxides

AbstractThe nucleophilic substitution reactions of 1,4‐dichlorobenzene chromium tricarbonyl (1) with the phenoxide anion were investigated. The substitution of the first chlorine was very fast and gave the mono‐substituted product in high yield. The substitution of the second chlorine group was significantly retarded by the presence of the phenoxy group incorporated during the first reaction and also due to the competing decomplexation reaction. The application of 1,4‐dichlorobenzene chromium tricarbonyl (1) to the synthesis of new monomers was demonstrated by the preparation of 2,2′‐bis[4‐(4‐chlorophenoxy)phenyl]propane (9). 2,2′‐Bis[4‐(4‐chlorophenoxyl)phenyl]propane (9) was synthesized by a nucleophilic substitution reaction of 4,4′‐isopropylidenediphenolate with 1,4‐dichlorobenzene chromium tricarbonyl (1) followed by decomplexation with I2. 2,2′‐Bis[4‐(4‐chlorophenoxy)‐phenyl]propane (9) was also synthesized via a three‐step reaction starting from the nucleophilic substitution reaction of 4,4′‐isopropylidenediphenol (7a) with 1‐chloro‐4‐nitrobenzene (10). 2,2′‐Bis[4‐(4‐chlorophenoxy)phenyl]propane (9) was polymerized by a Ni(0)‐catalyzed reaction to yield amorphous aromatic polyethers with number‐average molecular weights of up to 11,200 g/mol. © 1993 John Wiley & Sons, Inc.

Synthesis of new monomers having a secondary amino group by lithium alkylamide catalyzed addition reactions of primary amines with 1,4‐divinylbenzene

AbstractTo establish appropriate reaction conditions for the synthesis of new monomers having a secondary amino group, a lithium alkylamide catalyzed addition reaction of primary amines with styrene was examined as the model reaction. The selectivity of N‐alkyl‐2‐phenethylamines (2) and the rate constant of the reaction were determined. On the basis of results of the model reaction, new styrene derivatives having a secondary amino group (5) were synthesized by lithium alkylamide catalyzed addition reactions of primary amines with 1,4‐divinylbenzene.

Synthesis of new monomers having a primary amino group by lithium alkylamide catalyzed addition reaction of N‐alkylethylenediamines with 1,4‐divinylbenzene

Lithium alkylamide catalyzed addition reaction of N-alkylethylenediamines (1) with styrene was examined. It was found that N-alkyl-N-(2-phenethyl)ethylenediamine (3) was formed selectively in preference to N-alkyl-N′-(2-phenethyl)ethylenediamine (4). The identification of products was carried out by 13C NMR. On the basis of the results obtained, a new type of styrene derivative having a primary amino group (6) was synthesized by lithium alkylamide catalyzed addition reaction of 1 with 1,4-divinylbenzene.

Polymer Alloys—Their Structure, Morphology, and Properties

AbstractPolymeric materials with novel properties for new technological applications are increasingly obtained by combining existing polymers, while the synthesis of new monomers has receded into the background. These polymer combinations or “alloys” (polyblends) are characterized by their chemical composition, the conformation of the chain molecules, and the morphology, i.e. the state of order at supramolecular level. Multiphase constitution is a typical characteristic of these substances, with a decisive influence on their macroscopic properties. The morphology of multiphase polymer alloys can be controlled to a limited extent via the chemical composition of their components when homopolymers are mixed in the melt or as dispersions. Graft copolymerization, on the other hand, makes it possible to achieve the desired morphology at a given chemical composition. Furthermore, transprent two‐phase polymer alloys can be obtained under certain conditions. In multiphase polymers the reduction of stress without fracture, caused by mechanical loading will be treated using models. Certain combinations of properties such as hardness and toughness are connected with the coexistence of disperse and continuous phases. Equilibrium thermodynamical criteria for liquid mixtures wil be used to explain demixing phenomena in polymers. In the last few years it has become possible to determine the chain conformation experimentally using neutron scattering.