64919-15-9Relevant articles and documents
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.
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.
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.