537-39-3Relevant academic research and scientific papers
Triacylglycerol self-metathesis over highly chemoselective methyltrioxorhenium supported on ZnCl2-promoted mesoporous alumina
Pillai, Subha Kumaraswamy,Abidli, Abdelnasser,Belkacemi, Khaled
, p. 121 - 133 (2014)
Since triolein is the main constituent of most oils such as olive and high oleic sunflower oils, self-metathesis of this triacylglycerol at mild reaction conditions was investigated via a heterogeneous approach, in the presence of ZnCl2-modified mesoporous alumina supported methyltrioxorhenium (MTO) as a catalyst. Both intra and intermolecular metathesis reactions were observed. While, 9-octadecene, dimers and trimers of the triacylglycerol were isolated, intermolecular cyclization metathesis products were also obtained. The MTO-based catalyst was found to be highly chemoselective affording only desired metathesis product formation. In contrast, more than 50% of triolein was converted to undesired solid product in the presence of the homogeneous Grubbs 2nd generation catalyst. Triolein metathesis products were effectively separated by chromatographic techniques and identified using mass spectrometric and NMR analyses. The reported results show that 3%MTO/ZnCl2-Al 2O3-meso is an efficient and selective heterogeneous catalyst for bulky functionalized olefins metathesis such as triacylglycerols and edible oils, avoiding the use of costly homogeneous catalysts, or the use other rhenium-based catalysts with toxic promoters such as R4Sn.
Thermal degradation and isomerisation kinetics of triolein studied by infrared spectrometry and GC-MS combined with chemometrics
Christy, Alfred A.,Xu, Zhanfeng,Harrington, Peter de B.
experimental part, p. 22 - 31 (2010/02/28)
Triolein, a triglyceride containing oleic acid as the only acid moiety in the glyceride molecules has been isothermally treated at 280, 300, and 325 °C in glass vials under nitrogen atmosphere. The products formed during the thermal treatment at each temperature have been analysed both by infrared spectrometry and GC-MS. The GC-MS analysis was performed after derivatisation of the fatty acids into their methyl esters (FAMEs). Chemometric tools were used in determining the concentrations of the main products namely triolein and trieaidin in the thermally treated mixtures. The concentration profiles of the trielaidin formed during thermal treatment at the above three temperatures were used in determining activation energy for the cis-trans isomerisation of triolein. The combined analysis reveals that the thermal treatment induces not only cis-trans isomerisation but also fission and fusion in the molecules. Furthermore, migration of the double bond in oleic and elaidic acids forming cis and trans isomers of the 18:1 acid was also observed. The heat-induced isomerisation in triolein follows a zeroth order reaction with an activation energy 41 ± 5 kcal/mol.
Synthesis and physical properties of EOE and EEO, triacylglycerols containing elaidic and oleic fatty acids
Adlof,List
, p. 427 - 431 (2008/02/09)
Symmetrical and non-symmetrical triacylglycerols (TAG) containing oleic (O; 9c-18:1) and elaidic (E; 9t-18:1) acids were required as part of a study relating the physical characteristics and functionality of trans-containing TAG with the mouth feel, taste characteristics and related characteristics desired by consumers in frying oils and pastries. To replace the trans isomers in frying oils-a significant part of frying oils prepared by partial hydrogenation of vegetable oils-without loss of the sensory properties desired by consumers, required the initiation of a study relating the structure of trans-containing TAG with such characteristics as melting range, drop points, and other crystalline properties. Elaidic acid was esterified to trielaidin (EEE), and the EEE partially converted (glycerol/p-toluenesulfonic acid) to a mixture containing ca. 40% DAG (the 1,3- and 1,2-isomers). The DAG fraction was separated by silica gel chromatography, the 1,3-dielaidylglycerol (1,3EE-DAG) isomer isolated (structural purity >99%) by crystallization from acetone and esterified with oleic acid (O) to yield EOE. The 1(3)O-MAG was purchased commercially and esterified with E acid to prepare OEE. Both syntheses yielded multi-gram quantities of EOE and EEO, in 80-85% yields, and with structural purities >99%. Thus, by careful selection of the thermodynamically more-stable MAG or DAG precursors, the symmetrical EOE and non-symmetrical EEO isomers could be readily synthesized, and their drop point and melting point values determined. AOCS 2007.
1H-Nuclear magnetic resonance spectroscopic studies of saturated, acetylenic and ethylenic triacylglycerols
Lie Ken Jie, Marcel S.F.,Lam
, p. 155 - 171 (2007/10/03)
The 1H-NMR spectroscopic properties of 15 synthetic homologous saturated triacylglycerols of type AAA and 16 mixed saturated triacylglycerols of type ABA and AAB have been studied. Triacylglycerols containing short-chain fatty acids (2:0-6:0) are readily identified. Triacylglycerols containing medium- and long-chain fatty acid components are not differentiated. From the analysis of 19 acetylenic triacylglycerols of type AAA, ABA and AAB (containing positional isomers of acetylenic fatty acids), it is only possible to characterize triacylglycerols with acyl groups containing the acetylenic bond at the Δ2-Δ5 position. 1H-NMR analysis could not confirm the positions (α- or β-acyl) of the acetylenic acids in mixed triacylglycerols. In the study of 22 ethylenic triacylglycerols of type AAA containing positional isomers of (Z)- or (E)-ethylenic acids, molecules containing an ethylenic bond in the Δ2 position of the acyl chains were readily characterized, as the ethylenic protons in the α- and β-acyl chains were fully resolved. Triacylglycerols containing an unsaturated center at the position were characterized by the shifts of the 2-H protons. The spectra of the remaining triacylglycerol molecules were very similar and the position of the ethylenic system could not be determined by this technique.
Topical corticosteroid formulations
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, (2008/06/13)
This present invention relates to a solution for topical or local application comprising at least one corticosteroid; from about 1% to 4% by weight of solubilization agents consisting essentially of a combination of at least one glyceryl ester of a fatty acid of 6 to 22 carbon atoms and a betaine surfactant, from about 10% to 50% by weight of composition of an alkanol cosolvent, and from about 20% to 50% water.
Coal tar gel composition
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, (2008/06/13)
Compositions effective for topically treating skin conditions, especially psoriasis and eczema which contains as an essential ingredient coal tar in a gel base.
