- Design of dialkyl surfactants from nitrilotriacetic acid as head group
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New double-chain surfactants can be designed in which nitrilotriacetic acid plays the role of glycerol in phospholipids. The synthetic methodology is applied to the synthesis of (2-(bis(2-dodecylamino)-2-oxoethyl)amino)acetic acid. This is a symmetric dimeric surfactant but the methodology allows the synthesis of asymmetric double-chain surfactants as well. The Krafft temperature is 16-18 °C. The critical aggregation concentration of the new surfactant (4.76 × 10-5 mol dm-3 in NaOH 0.01 M and 25 °C; surface tension measurements) is two hundred times lower than that for sodium 2-dodecanamidoacetate, which can be considered its monoalkyl surfactant analog, indicating the enhanced surfactant properties resulting from the presence of two hydrophobic alkyl chains. The shape of the aggregates was investigated by transmission electron microscopy. At 40 °C, the main structure present in solution corresponds to vesicles and, from the size distribution of their radii, values of (0.34 ± 0.06)kT and 56.7 ± 2.6 nm were obtained for the effective bending elasticity constant and the spontaneous radius of curvature of vesicles, respectively. The Royal Society of Chemistry 2014.
- Trillo, Juan V.,Meijide, Francisco,Tato, Jose Vazquez,Jover, Aida,Soto, Victor H.,De Frutos, Santiago,Galantini, Luciano
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- Self-assembled dimerization of bis(crown ether)-2,2′-bibenzimidazoles
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Bis(crown ether)-2,2′-bibenzimidazole 1 and its 1-substituted derivatives were synthesized as new self-assembled motifs. UV-vis and 1HNMR titration experiments of 1 with potassium ions in a mixture of chloroform and methanol (1:1) were carried out. The stoichiometries and curve fitting analysis showed that a 2:2 complex of 1 with potassium ions was formed in a face-to-face fashion. 1-Monosubstituted bis(crown ether)-2,2′- bibenzimidazole 6a having a (dodecylaminocarbonyl)methyl group also gave a 2:2 complex with potassium ions. Structural analysis of the 2:2 complex of 6a with potassium ions was performed using various two-dimensional NMR techniques. Results suggested that, of eight or more possible conformational isomers, the one having the two substituent groups diagonally opposite each other was predominantly formed. Reversible association and dissociation of the 2:2 complex was observed after adding potassium ions and then removing them with an 18-crown-6-ether.
- Satake, Akiharu,Tanaka, Kazuo,Asakura, Hiroki,Okano, Masahiro,Hashimoto, Tsutsumu,Matsuura, You,Inaba, Yusuke,Oda, Tetsuhisa,Hirota, Shun,Koshino, Hiroyuki
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- Chemical and constitutional influences in the self-assembly of functional supramolecular hydrogen-bonded nanoscopic fibres
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A new series of secondary amides bearing long alkyl chains with π-electron-donor cores has been synthesized and characterised, and their self-assembly upon casting at surfaces has been studied. The different supramolecular assemblies of the materials have been visualized by using atomic force microscopy (AFM) and transmission electron microscopy (TEM). It is possible to obtain well-defined fibres of these aromatic core molecules as a result of the hydrogen bonds between the amide groups. Indeed, by altering the alkyl-chain lengths, constitutions, concentrations and solvent, it is possible to form different rodlike aggregates on graphite. Aggregate sizes with a lower limit of 6-8 nm width have been reached for different amide derivatives, while others show larger aggregates with rodlike morphologies which are several micrometers in length. For one compound that forms nanofibres, doping was 'performed by using a chemical oxidant, and the resulting layer on graphite was shown to exhibit metallic-like spectroscopy curves when probed with current-sensing AFM. This technique also revealed current maps of the surface of the molecular material. Fibre formation not only takes place on the graphite surface: nanometre scale rods have been imaged by using TEM on a grid after evaporation of solutions of the compounds in chloroform. Molecular modelling proves the importance of the hydrogen bonds in the generation of the fibres, and indicates that the constitution of the molecules is vital for the formation of the desired columnar stacks, results that are consistent with the images obtained by microscopic techniques. The results show the power of noncovalent bonds in self-assembly processes that can lead to electrically conducting nanoscale supramolecular wires.
- Puigmarti-Luis, Josep,Minoia, Andrea,Perez Del Pino, Angel,Ujaque, Gregori,Rovira, Concepcio,Lledos, Agusti,Lazzaroni, Roberto,Amabilino, David B.
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- 2,5-dialkylacetamide-1,3,4-thiadiazole for biodegradable lubricating oil additives, and preparation method thereof
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The invention discloses 2,5-dialkylacetamide-1,3,4-thiadiazole for biodegradable lubricating oil additives, and a preparation method thereof, wherein the structure of the 2,5-dialkylacetamide-1,3,4-thiadiazole is represented by a formula (1), R is a C1-C30 linear chain or branched chain alkyl group, 2,5-dimercapto-1,3,4-thiadiazole, n-butylamine, dodecylamine and chloroacetyl chloride are adopted as raw materials, triethylamine is adopted as an acid binding agent, dichloromethane is adopted as a solvent, an intermediate alkyl chloroacetamide is firstly obtained, and then the target product is obtained. According to the present invention, the source of the used raw materials is sufficient, the price of the used raw materials is low, the prepared intermediate chloroacetamide uses triethylamine as the acid binding agent, the synthesis process condition is mild, the process route is simple, the yield is high, and the obtained product has excellent extreme pressure wear resistance, has the good biodegradation performance after the use, and is the environmentally friendly multifunctional lubricating oil additive.
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Paragraph 0044
(2017/06/02)
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- Diversity oriented synthesis of novel haloglycolipids potentially useful for crystallization of integral membrane proteins
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A series of novel haloglycolipids were synthesized based on Cu(i) catalyzed Huisgen's [3 + 2] cycloaddition reaction of diversely functionalized azides and alkynes, using a mixture of N-bromosuccinimide and Cu(i) halide as the halogen source. Since halogen atoms, like bromine and iodine, with a very high scattering power facilitate the solving of crystal structures, the title haloglycolipids could prove to be invaluable in structure-based drug design involving membrane proteins as targets. This journal is the Partner Organisations 2014.
- Sahoo, Laxminarayan,Singhamahapatra, Anadi,Loganathan, Duraikkannu
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p. 2615 - 2625
(2014/04/17)
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- Synthesis and properties of 1-(2-(alkylamino)-2-oxoethyl) pyridinium chloride surfactants
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A series of 1-(2-(alkylamino)-2-oxoethyl) pyridinium chloride surfactants was designed and synthesised by two steps. Four new compounds were obtained. The structures of all the synthesised compounds have been characterised by IR, 1H NMR and elemental analyses. Surface activity and antibacterial activity of 1-(2-(alkylamino)-2-oxoethyl) pyridinium chloride surfactants were investigated. The critical micelle concentration and C20 values of the synthesised surfactants are low. The synthesised surfactants have good antibacterial activity for sulfate-reducing bacteria, metatrophic bacteria and iron bacteria in oil field injection water.
- Wang, Li-Yan,Qin, Hong-Lei,Wang, Lei,Huo, Shi-Chao,Zhao, Bing,Song, Bo,Yan, Tie
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p. 205 - 207
(2013/07/05)
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- Novel amide-based cationic surfactants as efficient corrosion inhibitors for carbon steel in HCl and H2SO4 media
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A variety of surface active compounds were synthesized by the quaternization of some straight chain amide derivatives with triethylamine or pyridine. Their structure FT-IR and 1H-NMR spectra were recorded. In addition their physical properties and corrosion prevention efficiencies were investigated. All compounds were tested with steel coupons in acidic media by the gravimetric method. As acidic media 1.5 M HCl and 1.5 M H2SO 4 were used and the corrosion inhibition tests fulfilled at room temperature for 24 h. Almost all prepared cationic surfactants showed efficient inhibition around their critical micelle concentrations. The effects of HCl concentration on corrosion inhibition of some synthesized compounds were also investigated. The corrosion tests were supported by contact angle measurements.
- Y?ld?r?m,?ztürk,?etin
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- LIPID CONTAINING FORMULATIONS
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Compositions and methods useful in administering nucleic acid based therapies, for example association complexes such as liposomes and lipoplexes are described.
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Page/Page column 121
(2008/06/13)
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- Synthesis and evaluation of antitubercular activity of glycosyl thio- and sulfonyl acetamide derivatives
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A series of glycosyl thioacetamide and glycosyl sulfonyl acetamide derivatives have been prepared following a convenient reaction protocol and evaluated for their antitubercular activity against Mycobacterium tuberculosis H37Rv. Amongst 32 compounds evaluated 3 compounds were effective in inhibiting mycobacterial growth at MIC of 6.25 μg/mL, 6 compounds at MIC of 3.125 μg/mL and 1 compound at MIC of 1.56 μg/mL. All active compounds were found nontoxic in Vero cell lines and mice bone marrow macrophages.
- Ghosh, Samir,Tiwari, Pallavi,Pandey, Shashi,Misra, Anup Kumar,Chaturvedi, Vinita,Gaikwad, Anil,Bhatnagar, Shalini,Sinha, Sudhir
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experimental part
p. 4002 - 4005
(2009/04/06)
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- Pyridine-derived heterocycles as potential photoacylating reagents
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We prepared several pyridine-derived heterocycles and investigated their photoacylating properties. Among representatives of 4 families of compounds (1-acetyl-7-azaindole, 1-acetyl-7-azaindoline, 2-acetamindpyridine and 2-amidopyrimidines), the 2-aminopyrimidine derivatives were the most promising candidates. Photoacylation of dodecylamine yields up to 47% were obtained, upon irradiation with UV light at 254 nm.
- Helgen, Celine,Bochet, Christian G.
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p. 797 - 805
(2007/10/03)
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- Soft antimicrobial agents: Synthesis and activity of labile environmentally friendly long chain quaternary ammonium compounds
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A series of soft quaternary ammonium antimicrobial agents, which are analogues to currently used quaternary ammonium preservatives such as cetyl pyridinium chloride and benzalkonium chloride, were synthesized. These soft analogues consist of long alkyl chain connected to a polar headgroup via chemically labile spacer group. They are characterized by facile nonenzymatic and enzymatic degradation to form their original nontoxic building blocks. However, their chemical stability has to be adequate in order for them to have antimicrobial effects. Stability studies and antibacterial and antiviral activity measurements revealed relationship between activity, lipophilicity, and stability. Their minimum inhibitory concentration (MIC) was as low as 1 μg/mL, and their viral reduction was in some cases greater than 6.7 log. The structure-activity studies demonstrate that the bioactive compounds (i.e., MIC for Gram-positive bacteria of 10μg/mL) have an alkyl chain length between 12 and 18 carbon atoms, with a polar headgroup preferably of a small quaternary ammonium group, and their acquired inactivation half-life must be greater than 3 h at 60 °C.
- Thorsteinsson, Thorsteinn,Másson, Már,Kristinsson, Karl G.,Hjálmarsdóttir, Martha A.,Hilmarsson, Hilmar,Loftsson, Thorsteinn
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p. 4173 - 4181
(2007/10/03)
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- REACTIONS OF DICHLOROACETYLENE WITH PRIMARY ALIPHATIC AMINES
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Primary aliphatic amines are good nucleophilic reagents which easily react with dichloroacetylene (DCA).The reactions of DCA with primary aliphatic amines have been studied and a mechanism of these reactions has been proposed and discussed.
- Pielichowski, Jan,Czub, Piotr
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p. 407 - 410
(2007/10/02)
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- Reduction of Nicotinamides, Flavins, and Manganese Porphyrins by Formate, Catalyzed by Membrane-Bound Rhodium Complexes
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Two polymerizable cyclopentadienyl-2,2'-bipyridinerhodium complexes and one amphiphilic rhodium complex have been synthesized and incorporated into the bilayers of vesicles formed from a polymerizable ammonium surfactant.Incorporation was achieved by chemical linkage (via a copolymerization reaction) or by physical absorption.The complexes are located at different positions in the bilayer, viz. in the hydrophobic interior or at the aqueous interface.The anchored rhodium complexes efficiently catalyze the reduction of both two-electron substrates (e.g., nicotinamides and flavin) and one-electron substrates (e.g., manganese(III) porphyrins) by sodium formate.Kinetic studies indicate that the rate-limiting step of the reaction is the reduction of the rhodium center by formate, leading to a rhodium(III) hydride or a rhodium(I) species.The three complexes showed different catalytic activities.Cyclic voltammetry and UV-vis measurements revealed that their reduction potentials ((2+) + 2e(-) ->/a values ((+) ->/- Rh(I) + H(+)) are also different.From the observed trends it is concluded that the catalytic activity of the rhodium complexes depends on its position in the bilayer.
- Esch, J. H. van,Hoffmann, M. A. M.,Nolte, R. J. M.
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p. 1599 - 1610
(2007/10/02)
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