We describe the synthesis and characterization of four new light and reduction sensitives poly(azoamide triazole)s, in which the azobenzene units are found along the main chain of the macromolecule. These polymers were prepared by the azide-alkyne cycloaddition reaction catalyzed with copper (I) (CuAAC). They were obtained in high yield and with apparent molecular weights in the range from 95 to 148 kDa. All poly(azoamide triazole)s are soluble in polar aprotic solvents, and two of them are also soluble in chloroform showing good coating and film-forming properties. They were characterized by Fourier transform infrared, nuclear magnetic resonance (NMR), ultraviolet-visible spectroscopy and gel permeation chromatography (GPC). The photoisomerization study of the synthesized polymers has been carried out by UV-Vis spectroscopy, as well as their trans-cis-trans reversibility behavior. Differential scanning calorimetry (DSC) and themogravimetric analysis (TGA) were used to investigate their thermal properties. Results show that the polymers were amorphous and stable up to 300 degrees C under nitrogen. The hydrolytic degradation of films of these polymers has been studied in vitro under various conditions of pH and temperature and was monitored by GPC. Furthermore, the presence of azo units along the polymer backbone as cleavable groups provides access to their degradation by reduction. In this sense, the degradation of polymers has also been studied using sodium dithionite as a mimic of the enzyme azoreductase. The results of these studies show that the polymers are stable enough under hydrolytic physiological conditions, but they degrade rapidly when sodium dithionite is used. A preliminary study of biocompatibility of polymers PAAT1 and PAAT4 has been carried out. A hemolysis study with human red blood cells (hRBC) and a cytotoxicity study with human gingival fibroblasts (HGnF) have been carried out. The results obtained suggest that these polymers could be good candidates to be used as drug coating materials. (C) 2021 The Author(s). Published by Elsevier Ltd.

Novel linear cationic poly(amide aminotriazole)s (PATnD) with secondary amine groups in the backbone were obtained by using azide-alkyne 1,3-dipolar cycloaddition reactions: metal- and solvent-free (thermal conditions, PATTnD) or copper(I)-catalyzed (Sharpless conditions, PATCnD). PATnD were investigated in vitro against strains of E. coli, P. aeruginosa, S. aureus, and S. epidermidis. Hemolytic activity was tested using human red blood cells (hRBC), and very low or no hemolytic activity was observed. The cytotoxicity of PATnD polymers against Human Gingival Fibroblasts (HGnF) cells was concentration-dependent, and significant differences between PATT1D and PATC1D were observed. The ability of these polymers to induce resistance against both Grampositive and Gram-negative bacteria was also assessed. Studied bacterial strains acquired resistance to catalytic polymers (PATCnD) in initial passages meanwhile resistance to thermal polymers (PATTnD) appears in later passages, being the increase of the minimum inhibitory concentration lower than in catalytic polymers. This result, together with the higher biocidal capacity of thermal polymers compared to catalytic ones, seems to suggest an influence of the regiospecificity of the polymers on their antibacterial characteristics. This study also demonstrates that PAT1D polymers, which do not appear to have strong hydrophobic residues, can exert significant antimicrobial activity against Gram-positive bacteria such as S. epidermidis. This pair of polymers, PATC1D and PATT1D, displays the greatest antimicrobial activity while not causing significant hemolysis along with the lowest susceptibility for resistance development of the polymers evaluated.

A set of poly(amide triazoles) (PT) was synthesized by azide-alkyne cycloaddition reactions from N,N-Bis[2-(propargylamido)ethyl]-N-[2-(tert-butoxycarbonylamino)ethyl] amine and 1,6-diazido-1,6-dideoxy-u-mannitol derivatives, having the secondary hydroxyl groups protected by removable acetal and/or acetyl groups. Either copper-catalyzed (CuAAC) as well as the classical thermal cycloaddition reactions were used to afford in good yields and medium molecular weight-linear PT featuring either 1,4- or 1,4/1,5-disubstituted triazole rings along the polymer chains, respectively. Full structural characterization of all PT was accomplished and comparatively studied. Protecting group removal allowed for modulating the flexibility and polarity of cationic polytriazoles (CP), entitling for structure-activity relationship insight of their self-assembling capabilities in the presence of nucleic acids. Hence, CP and DNA were formulated at different nitrogen-to-phosphate (N/P) ratios and the resulting polyplexes were characterized by Dynamic Light Scattering (DIS) and Transmission Electron Microscopy (TEM). All CP were able to condense DNA into positively-charged nanometric-sized and narrowpolydispersed particles that could mediated transfection into human embryonic stem cells (hESC) with negligible toxicity.

In this article, we describe the synthesis of three new linear poly(amide triazole)s prepared by click polyaddition reactions of a dialkyne-amide oligoamine monomer and diazide having amide linkage monomers, some of them derived from n-glucose. Both Cu(I)-catalyzed and metal-free click polymerization methods were used to prepare the poly(amide triazole)s which present their secondary amine functions Boc-protected. After deprotection, water-soluble linear cationic polymers were obtained having weight average molecular weights in the 9500-18,500 g mol(-1) range. All the polymers were characterized by nuclear magnetic resonance (NMR) and infrared spectroscopy (FTIR). Differential scanning calorimetry (DSC) revealed them to be amorphous, and in general, the polycationic polymers were less stable than the Boc-protected polymers as demonstrated by thermogravimetric analysis (TGA). Degradation studies of a water-soluble prototype polycationic polymer showed they are hydrolytically degradable. Polyplex formulations with DNA were characterized using dynamic light scattering (DLS). The polymers exhibit good ability to condense DNA into 100-200 nm size nanoparticles with positive zeta potential of about 20-50 mV at nitrogen/phosphate (N/P) ratios of 5 or higher. Transmission electron microscopy experiments revealed that polyplexes formed with nano-sized spheroidal structures.

Click Cu(I)-catalyzed polymerization of diynes and diazides was performed to obtain a novel type of linear copolymer, which were prepared from monomers derived from poly(ethylene glycol), 5, 5'-azo-disalicylic acid [olsalazine] and 1,4-butanediol diglycidyl ether. The resulting copolymers will carry ester and azo functions along the polymer backbone, so they will be sensitive to pH as well as be degraded by azoreductase enzymes present in the colonic microbiota. Most of the copoly(azoester triazole)s obtained were water soluble, and all of them were characterized by Fourier transform infrared, nuclear magnetic resonance (NMR), and gel permeation chromatography (GPC). Differential scanning calorimetry (DSC) revealed them to be amorphous, and in general, the polymers were stable up to 250 degrees C under nitrogen as demonstrated by thermogravimetric analysis (TGA). The degradation behavior of the polymers was evaluated in vitro. Degradation studies were carried out at 37 degrees C in buffered salt solution at pH 7.4, and were monitored by GPC and NMR spectroscopies. A biodegradation experiment of a water-soluble prototype polymer showed that they are biodegradable via a strain of Enterococcus faecalis. The experiment was monitored using ultraviolet visible spectroscopy. (C) 2019 Elsevier Ltd. All rights reserved.

ABSTRACTLinear [m,n]‐type polyurethanes (PUs) fully based on renewable materials are synthesized by interfacial polycondensation reaction of diamines derived from the amino‐acid cystine with (bis)chloroformates derived from alditols having L‐arabino or xylo configuration. The degradability of the new PUs has been enhanced by the introduction of disulfide linkages into the polymer backbone leading to a new group of stimulus‐responsive sugar‐based polyurethanes able to be degraded by glutathione under physiological conditions. All these polyurethanes are stable up to around 245°C, decomposing at higher temperatures through a one‐stage mechanism. The new materials display high chemical homogeneity and degradability in both hydrolytic and reductive environments, with reductions of above 90% in Mw. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 41304.

ABSTRACTCopoly(amide triazole)s, abbreviated as PGBMn, have been prepared by copolymerization of 6‐azido‐6‐deoxy‐2,3,4‐tri‐O‐methyl‐N‐(prop‐2‐yn‐1‐yl)‐d‐gluconamide and 6‐azido‐6‐deoxy‐2,3,4‐tri‐O‐benzyl‐N‐(prop‐2‐yn‐1‐yl)‐d‐gluconamide by catalyst‐ and solvent‐free 1,3‐dipolar Huisgen cycloaddition reaction. The resulting copolymers have a diblock or a random distribution of the monomeric units along the polymer chain. Their molecular weights are in the range of 70,000–90,000 and they were characterized by GPC and IR and NMR spectroscopies. Thermal studies revealed them to be amorphous and stable up to 200 °C under nitrogen. Their qualitative solubilities in various solvents and their water sorption have also been investigated. The copolymers are hydrophilic, one of them being water soluble. The in vitro hydrolysis of this copoly(amide triazole) was studied. The degradation study was carried out at 80 °C in buffered solution at pH 10, and was monitored by GPC, and NMR spectroscopy. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2015, 53, 413–421

ABSTRACT The copper(I)‐catalyzed alkyne‐azide cycloaddition (CuAAC) click polymerization has been used to obtain novel linear poly(ester triazole)s by reaction of bis ‐alkyne having ester linkage and bis ‐azido monomers, most of them derived from carbohydrates, such as glucose, arabinose, and erythrose, and therefore coming from natural renewable resources. The resulting polyesters had weight‐average molecular weights in the 11,500–148,000 range and were characterized by GPC, IR, and NMR spectroscopies. Thermal studies revealed them to be amorphous and stable up to 200 °C under nitrogen. Degradation studies showed that they were hydrolytically degradable. These studies were carried out at 50 °C in phosphate buffer solution at pH 7.4, and were monitored by GPC, and NMR spectroscopy. Finally, novel network hydrogels were obtained by crosslinking reaction of the poly(ester triazole) chains with hexamethylene diisocyanate. The water absorption and the kinetic parameters of the networks were studied. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2015 , 53 , 2481–2493

The click reaction between azides and alkynes is been increasingly employed in the preparation of polymers. In this article, we describe the synthesis and click polyaddition reaction of a new A-B-type amide monomerprepared from d-glucose as renewable resourcecontaining the alkyne and azide functions. Both Cu(I)-catalyzed and metal-free click polymerization methods were used to prepare glucose-derived poly(amide triazole)s. The resulting polymers had weight-average molecular weights in the 45,000-129,000 range and were characterized by GPC, IR, and NMR spectroscopies. Thermal and X-ray diffraction studies revealed them to be amorphous. Their qualitative solubilities in various solvents and their water sorption have been studied. The poly(amide triazole)s having the alcohol functions protected as methyl ether were water-soluble. The presence of the amide functions along the polymer chain made these polytriazoles degradable in the presence of sodium deuteroxide. The degradation was monitored by NMR analysis, and the degradation product was characterized by HRMS. (c) 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014, 52, 629-638

The synthesis, characterization, and some properties of new copolyesters analogous to poly(butylene terephthalate) (PBT), based on L-arabinaric and galactaric acids, are described. These copolyesters were obtained by polycondensation reaction in the melt of mixtures of methyl 2,3,4-tri-O-methyl-L-arabinarate or methyl 2,3,4,5tetra-O-methyl-galactarate and dimethyl terephthalate with 1,4-butanediol. Their weight-average molecular weights ranged between 10,000 and 34,000, with polydispersities ranging from 1.4 to 2.2. The composition of all the copolymers was analyzed by NMR, and was found to have a statistical microstructure. All these copolyesters were thermally stable, with degradation temperatures well above 300 degrees C. The melting temperature and crystallinity decreased in both series, and the glass transition temperature increased and decreased respectively, for the PBTGa and PBTAr series with increasing amounts of aldaric units in the copolyester chain. Only PBT-derived copolyesters containing a maximum of 30% aldaric units showed discrete scattering characteristic of crystalline material. (C) 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 1168-1177, 2009

The synthesis, characterization, and some properties of new copolyesters of poly(butylene terephthalate) (PBT) and poly(ethylene terephthalate) (PET) based on L-arabinitol and xylitol are described. These copolyesters were obtained by polycondensation reaction in the melt of mixtures of 1,4-butanediol or ethylene glycol and 2,3,4-tri-O-benzyl-L-arabinitol or 2,3,4-tri-O-benzyl-xylitol with dimethyl terephthalate. Their weight-average molecular weights ranged between 7000 and 55,000, with polydispersities ranging from 1.4 to 4.7. Copolymers containing 1,4-butanediol could be analyzed by NMR, and were found to have a statistical microstructure. All these copolyesters were thermally stable, with degradation temperatures well above 300 degrees C. With increasing amounts of alditol in the copolyester, the melting temperature and crystallinity decreased in both series, and the glass transition temperature increased for the PBT series and decreased for the PET series. Only PBT-derived copolyesters containing a maximum of 10% alditol units showed discrete scattering characteristic of crystalline material. No substantial differences in either structure or properties were observed between the L-arabinitol and xylitol copolyester series. (C) 2008 Wiley Periodicals, Inc.

A set of linear [m,n]-type polyurethanes was synthesized by polycondensation in solution from hexamethylene diisocyanate and 4,4 '-methylene-bis(phenyl isocyanate) with alditols. Threitol, arabinitol, and xylitol bearing the secondary hydroxy groups blocked as methyl ethers were used. Either regioregular or nonregioregular polymers (depending on the configuration of the alditol) were obtained in high yields and with number-average molecular weights within the 20,000-30,000 range. All these polyurethanes were amorphous with T, being highly dependent on the aliphatic or aromatic nature of the diisocyanate used, but scarcely depending on the chemical structure of the alditol moiety. They were found to be stable up to near 300 degrees C, decomposing at higher temperatures through a complex three-stage mechanism. Polyurethanes obtained from threitol did not show significant enhancement of hydrolytic degradability as compared with polyurethanes obtained from 1,4-butanediol. Conversely, polyurethane prepared from xylitol and hexamethylendiisocyanate was found to be almost fully hydrolyzed in 1 month when incubated in water either at 80 degrees C and pH 7.4 or at 37 degrees C and pH 10. It was concluded that the alditol size seems to be of prime importance in determining the hydrodegradability of these sugar containing polyurethanes.

The hydrolytic degradation of a series of homo- and co-polyesters analogous to poly(ethylene terephthalate) (PET) and poly(ethylene isophthalate) (PEI), prepared from carbohydrate-based monomers, was studied. The degradation process was carried out at temperatures of approximately 10°C above the Tg of the polymers. All the studied polyesters were found to degrade at significant rates, and degradability showed a clear dependence on the configuration of the sugar units present in the polymer chain. No weight loss was detected upon degradation, apparently due to the non-solubility of the degraded products in the aqueous incubation medium. Hydrolysis of co-polyesters took place preferentially by cleavage of the ester groups of the sugar units.

The synthesis, characterization, and some properties of new copolyesters of poly(butylene terephthalate) based on L-arabinitol and xylitol are described. These copolyesters were obtained by polycondensation reaction in the melt Of mixtures of 1,4-butanediol and 2,3,4-tri-O-methyl-L-arabinitol or 2,3,4-tri-O-methylxylitol with dimethyl terephthalate. Their weight-average molecular weights ranged between 20 000 and 40 000, with polydispersities oscillating from 1.5 to 2.2. All them had a statistical microstructure and were thermally stable well above 300 degrees C. Copolyesters containing up to 30% of alditol-derived units were found to be crystalline and to adopt the same crystal structure as the parent homopolyester poly(butylene terephthalate). The melting temperature and crystallinity were observed to decrease, and the glass transition temperature to increase, with increasing amounts of alditol incorporated in the copolyester. Crystallizability was depressed by copolymerization, whereas the hydrolytic degradability was significantly enhanced by the presence of alditol units. No relevant differences in either structure or properties were observed between the L-arabinitol and xylitol copolyester series.

The synthesis and characterization of a new series of aromatic polyesters based on D-mannitol and galactitol are described. These polyesters were obtained by polycondensation reaction of the terephthaloyl chloride or isophthaloyl chloride and 2,3,4,5-tetra-O-methyl-D-mannitol or 2,3,4,5-tetra-O-methyl-galactitol in o-dichlorobenzene. All the new polyesters were characterized by elemental analyses, GPC, IR, and NMR. They were soluble in chloroform, but insoluble in water and other polar oxygenated solvents. They showed a notable hygroscopicity, lower for those containing isophthalic units. DSC and X-ray diffraction studies showed that D-mannitol-based polyesters were stiffer and less crystalline than those derived from galactitol, which presented a noticeably lower thermal stability. (c) 2005 Wiley Periodicals, Inc.

The synthesis and characterization of new aromatic homo- and copolyesters based on L-arabinitol and xylitol are described. These polymers were obtained by polycondensation reaction of the 2,3,4-tri-O-methyl-L-arabinitol or 2,3,4-tri-O-methyl-xylitol, or their mixtures with ethylene glycol, with terephthaloyl chloride or isophthaloyl chloride in o-dichlorobenzene or in the melt phase from the corresponding methyl phthalates. All the polymers were characterized by GPC, IR, and NMR. Their M-W values ranged between 11,500 and 46,500, with polydispersities from 1.5 to 2.3. They were found to be soluble in chloroform, but insoluble in water. In contrast with the homopolymers completely made with EG, they showed a significant hygroscopicity. DSC and TGA studies showed that the melting temperature of polyethylene terephthalate is depressed by the presence of pentitol units, whereas the thermal stability is kept above 350 C. Only copolyesters containing 10% or less of pentitol units showed melting and produced X-ray diffraction patterns characteristic of crystalline material. D-Arabinitol-based homopolyesters appeared to be more crystalline than those derived from xylitol and also presented a higher thermal stability. (c) 2005 Wiley Periodicals, Inc.