- Synthesis of the Hemoglobin-Conjugated Polymer Micelles by Thiol Michael Addition Reactions
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Amphiphilic triblock copolymers mPEG-b-PMAC-b-PCL are synthesized using methoxyl poly(ethylene glycol), cyclic carbonic ester monomer including acryloyl group, and ε-caprolactone. Copolymers are self-assembled into core–shell micelles in aqueous solution. Thiolated hemoglobin (Hb) is conjugated with micelles sufficiently through thiol Michael addition reaction to form hemoglobin nanoparticles (HbNs) with 200 nm in diameter. The conjugation of Hb onto the micelle surface is further confirmed by X-ray photoelectron spectroscopy. Feeding ratio of copolymer micelles to Hb at 1:3 would lead to the highest hemoglobin loading efficiency 36.7 wt%. The UV results demonstrate that the gas transporting capacity of HbNs is well remained after Hb is conjugated with polymeric micelles. Furthermore, the obtained HbNs have no obvious detrimental effects on blood components in vitro. This system may thus have great potential as one of the candidates to be developed as oxygen carriers and provide a reference for the modification of protein drugs. (Figure presented.) .
- Qi, Yanxin,Li, Taihang,Wang, Yupeng,Wei, Xing,Li, Bin,Chen, Xuesi,Xie, Zhigang,Jing, Xiabin,Huang, Yubin
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- Homopolymerization and copolymerization kinetics of trimethylene carbonate bearing a methoxyethoxy side group
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The polymerization kinetics of 5-[2-{2-(2-methoxyethoxy)ethyoxy}-ethoxymethyl]-5-methyl-trimethylene carbonate (TMCM-MOE3OM) synthesized using the organocatalyst 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) were studied and compared to those with the commonly used catalyst/initiator for ring-opening polymerization of cyclic carbonates and esters, stannous 2-ethylhexanoate. Further, the utility of each of these catalysts in the copolymerization of TMCM-MOE3OM with trimethylene carbonate (TMC) and l-lactide (LLA) was examined. Regardless of conditions with either catalyst, homopolymerization of TMCM-MOE3OM yielded oligomers, having number average molecular weight less than 4000 Da. The resultant molecular weight was limited by ring-chain equilibrium as well as through monomer autopolymerization. Interestingly, autopolymerization of TMC was also achieved with DBU as the catalyst. Copolymerization with TMC using stannous 2-ethylhexanoate as the catalyst yielded random copolymers, while diblock copolymers were formed by copolymerization with LLA. With DBU as the catalyst, copolymers with LLA could not be formed, while blocky copolymers were formed with TMC. These findings should be useful in the incorporation of this monomer in the design of polymer biomaterials.
- Chen, Fei,Amsden, Brian G.
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Read Online
- An investigation of siloxane cross-linked hydroxyapatite-gelatin/copolymer composites for potential orthopedic applications
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Causes of bone deficiency are numerous, but biomimetic alloplastic grafts provide an alternative to repair tissue naturally. Previously, a hydroxyapatite-gelatin modified siloxane (HAp-Gemosil) composite was prepared by cross-linking N,N'-bis[(3-trimethoxysilyl)propyl]ethylene diamine (enTMOS) around the HAp-gel nanocomposite particles, to mimic the natural composition and properties of bone. However, the tensile strength remained too low for many orthopedic applications. It was hypothesized that incorporating a polymer chain into the composite could help improve long range interaction. Furthermore, designing this polymer to interact with the enTMOS siloxane cross-linked matrix would provide improved adhesion between the polymer and the ceramic composite, and improve mechanical properties. To this end, copolymers of l-lactide (LLA), and a novel alkyne derivatized trimethylene carbonate, propargyl carbonate (PC), were synthesized. Incorporation of PC during copolymerization affects properties of copolymers such as molecular weight, Tg, and %PC incorporation. More importantly, PC monomers bear a synthetic handle, allowing copolymers to undergo post-polymerization functionalization with graft monomers to specifically tailor the properties of the final composite. For our investigation, P(LLA-co-PC) copolymers were functionalized by an azido-silane (AS) via copper catalyzed azide-alkyne cycloaddition (CuAAC) through terminal alkyne on PC monomers. The new functionalized polymer, P(LLA-co-PC)(AS) was blended with HAp-Gemosil, with the azido-silane linking the copolymer to the silsesquioxane matrix within the final composite. These HAp-Gemosil-P(LLA-co-PC) (AS) composites were subjected to mechanical and biological testing, and the results were compared with those from the HAp-Gemosil composites. This study revealed that incorporating a cross-linkable polymer served to increase the flexural strength of the composite by 50%, while maintaining the biocompatibility of HAp-Gemosil ceramics.
- Dyke, Jason Christopher,Knight, Kelly Jane,Zhou, Huaxing,Chiu, Chi-Kai,Ko, Ching-Chang,You, Wei
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Read Online
- Selective monobenzylation of 2,2-bis(hydroxymethyl)propionic acid (bis-MPA) to yield an AB linear monomer and analogous linear oligomers
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The synthesis of a mono-benzylated AB monomer based on bis-MPA is explored and accomplished via a three-step synthesis without column chromatography. This optimized synthesis utilizes a generic acid-catalyzed esterification of bis-MPA to the ethyl ester.
- Giesen, Joseph A.,Grayson, Scott M.
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supporting information
(2020/05/28)
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- MANUFACTURING METHOD OF TRIMETHYLENE CARBONATE DERIVATIVE
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PROBLEM TO BE SOLVED: To enable easily synthesizing a trimethylene carbonate derivative containing no ester bond. SOLUTION: The manufacturing method of a trimethylene carbonate derivative having a process for obtaining a compound A represented by the following formula (2) by protecting hydroxyl groups at 2 locations of trimethylolalkane represented by the following formula (1) by a protection agent at same time, a process for obtaining a compound B represented by the formula (3) and having 2 hydroxyl groups by reducing the compound A by a reductant and deprotecting only one of the 2 locations, a process for obtaining a trimethylene carbonate derivative represented by the formula (4) by carbonylating 2 hydroxyl groups of the compound B. SELECTED DRAWING: None COPYRIGHT: (C)2019,JPOandINPIT
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Paragraph 0031; 0032
(2019/10/01)
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- Polymeric depots for localization of agent to biological sites
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Provided herein are polymeric particles and compounds and processes that can be used to prepare polymer-based particles and methods of using those particles to localize or concentrate a subsequently delivered agent to an in vivo site.
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Page/Page column 63
(2019/04/26)
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- Novel synthesis method of ester free trimethylene carbonate derivatives
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Ester free poly(trimethylene carbonate) (PTMC) derivatives show biocompatibility and biodegradability and do not generate any acidic compounds after decomposition. Their syntheses methods are limited however, hampering their material application. Herein, we established a novel synthesis route of ester free trimethylene carbonate (TMC) derivatives. The novel synthesis route was described using six aldehydes and one ketone as starting compounds. The key reaction is the selective deprotection from two protected hydroxyl groups in the cyclic acetal structure by diisobutylaluminium hydride. This novel synthesis route means that it is possible to convert aldehyde group to ether groups in the side chain of TMC. Conventionally, only a substituent derived from a primary alcohol was introduced into the side chain. We therefore succeeded in decreasing the number of reaction steps from five to three, compared with the conventional route. Furthermore, the development of a novel synthesis route enabled the introduction of substituents derived from secondary alcohols, anticipating the creation of further types of ester free TMC derivatives.
- Nobuoka, Hiroaki,Ajiro, Hiroharu
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p. 164 - 170
(2019/01/04)
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- Efficient synthesis of ether phosphonates using trichloroacetimidate and acetate coupling methods
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A series of ether phosphonates have been prepared by trichloroacetimidate and acetate coupling methods. Trichloroacetimidates or acetates were treated with primary and secondary alcohols as O-nucleophiles in the presence of catalytic TMSOTf to afford 21 examples of diethyl alkyloxy(substitutedphenyl)methyl phosphonates via C-O bond formation in 55-90% yields and short reaction time.
- Fathalla, Walid,Ali, Ibrahim A. I.,Pazdera, Pavel
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p. 7385 - 7395
(2018/03/01)
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- Preparation method of compound
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The invention discloses a preparation method of a compound. The compound has a structure shown in the formula I. The preparation method comprises that a compound II and a compound III undergo a reaction to produce a solution of an intermediate IV under action of an acid/azole complex, a compound V is added into the solution of the intermediate IV, the mixture undergoes a reaction to produce a solution of an intermediate VI under action of an acid/azole complex, a butanone peroxide solution is slowly added into the solution of the intermediate VI so that a solution of an intermediate VII is obtained, a hydrazine acetate solution is slowly added into the solution of the intermediate VII so that a compound VIII is obtained, and the compound VIII and the compound III undergo a reaction under action of an acid/azole complex to produce a compound I.
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Paragraph 0087-0090
(2017/07/19)
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- A METHOD OF MAKING A POLYMER PREFERABLY AN (ALKYL)ACRYLOYL POLYCARBONATE, THE POLYMER AND (ALKYL)ACRYLOYL POLYCARBONATE OBTAINED, AND A BIODEVICE COMPRISING SAME
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The invention relates to a method for making a polymer wherein during the polymerisation is incorporated in the polymer chain by ring opening polymerisation a cyclic (alkyl)acryloyl carbonate having the formula (4): wherein R1 and R2 each independently are hydrogen, methyl or ethyl. Preferrable the polymer is an (alkyl)acryloyl polycarbonate such that at least one first monomer a cyclic (alkyl)acryloyl carbonate having the formula (4). The (alkyl)acryloyl polyester may be modified and used in biodevices.
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Page/Page column 16-17
(2011/02/24)
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- Versatile synthesis of functional biodegradable polymers by combining ring-opening polymerization and postpolymerization modification via michael-type addition reaction
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Various functional biodegradable polymers were readily prepared based on novel cyclic carbonate monomers, acryloyl carbonate (AC) and methacryloyl carbonate (MAC), by combining ring-opening polymerization (ROP) and Michael-type conjugate addition. AC and MAC monomers were synthesized in four straightforward steps from 1,1,1-tris(hydroxymethyl)ethane with good overall yields (ca. 40%). AC and MAC were able to copolymerize with ε-caprolactone (ε-CL) and D,L-lactide (LA) in toluene at 110°C using stannous octoate as a catalyst, yielding biodegradable copolymers with controlled (meth)acryloyl functional groups and molecular weights. The acryloyl groups were amenable to the Michaeltype conjugate addition with varying thiol-containing molecules such as 2-mercaptoethanol, 3-mercapto-propanoic acid, cysteamine, cysteine, and arginine-glycine-aspartic acid-cysteine (RGDC) peptide under mild conditions, to provide biodegradable materials with vastly different functionalities (e.g., hydroxyl, carboxyl, amine, amino acid, and peptides) and properties (e.g., hydrophilicity, cell adhesion). Notably, 100% functionalization was achieved with 2-mercaptoethanol, cysteamine and cysteine. Initial cell culture studies demonstrated enhanced cell adhesion and growth on films containing functional RGDC peptides as compared to those of the parent copolymer. Therefore, combination of ROP and Michael-type conjugate addition provides a versatile access to diverse types of functional biodegradable materials.
- Chen, Wei,Yang, Huicui,Wang, Rong,Cheng, Ru,Meng, Fenghua,Wei, Wenxiang,Zhong, Zhiyuan
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experimental part
p. 201 - 207
(2011/10/01)
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- Films and Particles
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Described herein are compounds and processes that can be used to prepare polymer-based films, particles, gels and related compositions, and processes for delivery of agents, and other uses.
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Page/Page column 35
(2008/06/13)
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- Dendritic-linear miktoarm star polymers from orthogonal protected initiators
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The synthesis of miktoarm dendritic-linear star copolymers in a tandem "core-in"/"core-out" approach is described. This synthetic approach is enabled by rational design and synthesis of an orthogonal protected compound containing six sites arranged in an
- Glauser, Thierry,Stancik, Cheryl M.,Moeller, Michael,Voytek, Sarah,Gast, Alice P.,Hedrick, James L.
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p. 5774 - 5781
(2007/10/03)
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- Synthesis and structure of 2-aryl-5,5-disubstituted-1,3-dioxanes and conversion into chiral (1,1,1-trishydroxymethyl) methane derivatives
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Pentaerythritol, (1,1,1-trishydroxymethyl)methyl methane and (1,1,1-trishydroxymethyl)nitromethane are converted into 2-aryl-5,5-bis(hydroxymethyl), 2-aryl-5-hydroxymethyl-5-methyl- or 2-aryl-5-hydroxymethyl-5-nitro-1,3-dioxanes and a range of derivatives. X-Ray and NMR analysis establishes that the latter is obtained as a single diastereomer whose structure is unambiguously determined. These materials can be elaborated to chiral derivatives of the starting (1,1,1-trishydroxymethyl) methanes.
- Gardiner, John M,Mather, Paul,Morjan, Ramy,Pritchard, Robin G,Warren, John E,Cooper, Malcolm L,Ferwanah, Abd El-Rahman S,Abu-Tiem, Omar S
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p. 2091 - 2094
(2007/10/03)
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