- Use of glycerol carbonate in an efficient, one-pot and solvent free synthesis of 1,3-sn-diglycerides
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An efficient solvent-free synthesis of a variety of highly pure 1,3-sn-diglycerides (1,3-sn-diacylglycerols) in a two-step one pot process is described. Heating glycerol carbonate (4-hydroxymethyl-1,3-dioxolan-2-one) with fatty acid anhydrides 2a-d affords 1:1 mixtures of glycerol carbonate fatty esters 3a-3d and the corresponding fatty acids. Further heating the reaction mixtures in the presence of catalytic amounts of 1,4-diazabicyclo[2.2.2]octane (DABCO) at 195-200 °C yields highly pure 1,3-sn-diglycerides 4a-4d.
- Kargar, Mojgan,Hekmatshoar, Rahim,Ghandi, Mehdi,Mostashari, Abdoljalil
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p. 259 - 264
(2013/07/27)
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- Synthesis and characterization of long chain alkyl acyl carnitine esters. Potentially biodegradable cationic lipids for use in gene delivery
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A series of alkyl acyl carnitine esters (alkyl 3-acyloxy-4- trimethylammonium butyrate chloride) were synthesized as potential biocompatible cationic lipids for use in gene transfer. The physicochemical properties of the lipids, liposomes prepared from them, and their complexes with DNA were characterized by differential scanning calorimetry (DSC), particle size, potential, and surface monolayer measurements. The transition temperatures and behavior at an air-water interface for this series are similar to phosphatidylcholines with the same hydrocarbon chain length. The physical properties of the L derivatives were not significantly different from the DL derivatives. At 70 °C, the acyl chains were readily hydrolyzed at pH 7. The influence of the aliphatic chain length (n = 12-18) on transfection efficiency in vitro was determined using cationic liposomes prepared from these lipids or their mixtures with the helper lipids, dioleoylphosphatidylethanolamine (DOPE), dioleoylphosphatidylcholine, monooleoylglycerol, and cholesterol (Chol). The mixture of myristyl 3- myristoyloxy-4-trimethylammonium butyrate chloride (MMCE, 4d) with DOPE at a 1:1 molar ratio mediated the highest transfection efficiency in cell culture. The mixture of oleyl 3-oleoyloxy-4-trimethylammonium butyrate chloride (OOCE, 4f) with Chol at a 1:1 molar ratio gave the highest transfection efficiency after intravenous administration in mice. In vivo gene expression using 4f was comparable to values obtained with the best cationic lipids reported to date.
- Wang, Jinkang,Guo, Xin,Xu, Yuhong,Barron, Lee,Szoka Jr., Francis C.
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p. 2207 - 2215
(2007/10/03)
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- A NEW SYNTHESIS OF CARBOXYLIC AND CARBONIC ACID ANHYDRIDES USING PHASE TRANSFER REACTIONS
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Acyl chlorides and alkylchloroformates smoothly reacted with one molar equivalent of sodium hydroxide, using liquid-liquid phase transfer conditions to afford high yields of the corresponding symmetrical carboxylic and carbonic hemiester anhydrides.Unstable anhydrides such as 4-nitrobenzoic, 2-furoic and methacrylic anhydrides, which are otherwise difficult to obtain, were easily prepared by this method.The reaction mechanism does not seem to involve intermediate hydrolysis of half the acid chloride into the corresponding sodium carboxylate.
- Plusquellec, Daniel,Roulleau, Fabienne,Lefeuvre, Martine,Brown, Eric
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p. 2471 - 2476
(2007/10/02)
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- UNE METHODE SIMPLE ET RAPIDE DE PREPARATION DES ANHYDRIDES D'ACIDES CARBOXYLIQUES A PARTIR DE LEURS CHLORURES D'ACIDES, AVEC CATALYSE PAR TRANSFERT DE PHASE
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Symmetrical anhydrides of carboxylic acids were readily obtained, and in high yields under phase transfer conditions, i.e. by reacting the appropriate acid chloride in toluene solution (containing 0.1 eq. of n-Bu4N+ Cl-), with 20percent aqueous sodium hydroxide solution.
- Roulleau, Fabienne,Plusquellec, Daniel,Brown, Eric
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p. 4195 - 4196
(2007/10/02)
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