64919-15-9Relevant academic research and scientific papers
Zinc-catalyzed depolymerization of polyethers to produce valuable building blocks
Enthaler, Stephan
, p. 850 - 859 (2014/06/23)
The recycling of polymers continues to be a significant matter for a sustainable society. In particular, the conversion of end-of-life polymers to monomers or suitable low-molecular weight chemicals creates a feedstock for new high-quality polymeric materials and contributes to conserve resources and allow overall an efficient waste-managing system. In the present study, we have set up a straightforward methodology for the depolymerization of artificial polyethers applying cheap and abundant zinc( II) salts as precatalysts. In the presence of bio-based fatty acid chlorides as depolymerization reagent well-defined chloroesters were accessible in good to excellent yields. Moreover, acetic anhydride and fatty acids were applied as depolymerization reagents resulting in the formation of diacetates in moderate yields. In both cases the obtained products (chloroesters, diacetates) can be useful building blocks in polymerization chemistry. Noteworthy, overall a recycling of polyethers are possible. Springer Science+Business Media New York 2014.
Cationic imidazolium monomeric surfactants: Their synthesis and surface active properties
Ahmad, Ishtiaque,Patial, Pankaj,Kaur, Charanjeet,Kaur, Satindar
, p. 269 - 277 (2014/03/21)
A series of long-chain ester-based water-soluble cationics have been synthesized by using renewable raw materials like fatty acids and halogenated alcohols. The surface activity of the molecules has been determined by measurement of their conductance and surface tension in aqueous solution. The dynamics of surface activity of these surfactants have also been investigated in the presence of sodium halides (NaCl and NaBr) by surface tension measurement. A series of useful parameters like critical micelle concentration (CMC), surface tension at the CMC (γCMC), adsorption efficiency (pC 20), effectiveness of surface tension reduction (ΠCMC), Gibbs free energy of the micellization (ΔG0mic) and Gibbs free energy of adsorption (ΔG0ads) have been determined from the measurements obtained by surface tension and conductivity methods. Further with the application of the Gibbs adsorption isotherm, maximum surface excess concentration (Γmax) and minimum surface area/molecule (A min) at the air-water interface were also estimated. Thermal stability of these long chain cationics have been measured by thermal gravimetric analysis under a nitrogen atmosphere. Analysis of thermal stability measurement indicated that the thermal stability of these long chain imidazoliums increases with an increase in chain length.
Gemini pyridinium surfactants: Synthesis and their surface active properties
Patial, Pankaj,Shaheen, Arifa,Ahmad, Ishtiaque
, p. 929 - 935 (2014/09/30)
New pyridinium Gemini surfactants have been synthesized by esterification of renewable fatty acids with halogenated alcohols furnishing respective esters (2-chloroethyl hexadecanoate, 2-chloroethyl tetradecanoate, 2-chloroethyl dodecanoate, 2-bromoethyl hexadecanoate, 2-bromoethyl tetradecanoate and 2-bromoethyl dodecanoate) followed by their subsequent treatment with 4,4′-trimethylenedipyridine resulting into the formation of title Gemini surfactants: (4,4′-(propane-1,3-diyl)bis(1-(2-(hexadecanoyl oxy) ethyl) dipyridinium chloride(7), (4,4′-(propane-1,3-diyl)bis(1-(2-(tetradecanoyl oxy) ethyl) dipyridinium chloride (8), 4,4′-(propane-1,3-diyl)bis(1-(2- (dodecanoyl oxy) ethyl) dipyridinium chloride (9), (4,4′-(propane-1,3- diyl)bis(1-(2-(hexadecanoyl oxy) ethyl) dipyridinium bromide (10), (4,4′-(propane-1,3-diyl)bis(1-(2-(tetradecanoyl oxy) ethyl) dipyridinium bromide (11), 4,4′-(propane-1,3-diyl)bis(1-(2-(dodecanoyl oxy) ethyl) dipyridinium bromide (12). Their identifications are based on IR, 1H-, 13C-NMR, DEPT, COSY and mass spectral studies. Their surface active properties are also evaluated on the basis of surface tension and conductivity measurements and thermal stability of these long chain cationics Gemini surfactants have been measured by thermal gravimetric analysis under nitrogen atmosphere.
Dodecanoic acid derivatives: Synthesis, antimicrobial evaluation and development of one-target and multi-target QSAR models
Sarova, Devinder,Kapoor, Archana,Narang, Rakesh,Judge, Vikramjeet,Narasimhan, Balasubramanian
experimental part, p. 769 - 781 (2012/05/20)
In this study a series of dodecanoic acid derivatives (1-30) were synthesized and evaluated for in vitro antimicrobial activity against the panel of Gram positive, Gram negative bacterial and fungal strains. 4-Nitro phenyl dodecanoate (4) and quinolin-8-yl dodecanoate (5) emerged as most effective antibacterial agents, and 1-(4-benzylpiperazin- 1-yl) dodecan-1-one (15) was found to be the most effective antifungal agent amongst the synthesized dodecanoic acid derivatives. Quantitative structure activity relationship (QSAR) studies performed by the development of one-target and multi-target models indicated that multitarget model was effective in describing the antimicrobial activity of dodecanoic acid derivatives as well demonstrated the importance of topological parameter, zero-order molecular connectivity index (0X). Springer Science+Business Media, LLC 2010.
Sustained release pharmaceutical compositions
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Page/Page column 5, (2008/06/13)
The present invention relates to a pharmaceutical composition comprising a salt of quaternary ammonium of an acid drug in the form of a suspension or an emulsion, suitable for parenteral administration and providing a sustained release of the drug. In one preferred embodiment, the present invention is directed to a long term sustained release composition for parenteral administration, comprising a salt of heparin or low molecular weight heparin in an emulsion with a salt of acylcholine, for the prevention and treatment of venous thrombosis and pulmonary embolism.
Copper(I)-promoted dechlorinative Surzur-Tanner rearrangement of 2,2,2-trichloroethyl carboxylates
Ram, Ram N.,Meher, Nabin Kumar
, p. 145 - 147 (2007/10/03)
(Matrix presented) 2,2,2-Trichloroethyl carboxylates undergo highly efficient dechlorinative Surzur-Tanner rearrangement with 2 equiv of a 1:1 molar mixture of CuCl and bpy in boiling DCE to give 1-chloroethenyl carboxylates in which copper appears to play an important role, probably by coordinating the initial radical or as a Lewis acid catalyst.
