112-67-4Relevant articles and documents
Analysis of Intact Cholesteryl Esters of Furan Fatty Acids in Cod Liver
Hammann, Simon,Wendlinger, Christine,Vetter, Walter
, p. 611 - 620 (2015)
Furan fatty acids (F-acids) are a class of natural antioxidants with a furan moiety in the acyl chain. These minor fatty acids have been reported to occur with high proportions in the cholesteryl ester fraction of fish livers. Here we present a method for the direct analysis of intact cholesteryl esters with F-acids and other fatty acids in cod liver lipids. For this purpose, the cholesteryl ester fraction was isolated by solid phase extraction (SPE) and subsequently analyzed by gas chromatography with mass spectrometry (GC/MS) using a cool-on-column inlet. Pentadecanoic acid esterified with cholesterol was used as an internal standard. GC/MS spectra of F-acid cholesteryl esters featured the molecular ion along with characteristic fragment ions for both the cholesterol and the F-acid moiety. All investigated cod liver samples (n = 8) showed cholesteryl esters of F-acids and, to a lower degree, of conventional fatty acids. By means of GC/MS-SIM up to ten F-acid cholesteryl esters could be determined in the samples. The concentrations of cholesteryl esters with conventional fatty acids amounted to 78-140 mg/100 g lipids (mean 97 mg/100 g lipids), while F-acid cholesteryl esters were present at 47-270 mg/100 g lipids (mean 130 mg/100 g lipids).
Amphiphilic hyperbranched copolymers bearing a hyperbranched core and dendritic shell: Synthesis, characterization and guest encapsulation performance
Liu, Yi,Fan, You,Liu, Xun-Yong,Jiang, Song-Zi,Yuan, Yuan,Chen, Yu,Cheng, Fa,Jiang, Shi-Chun
, p. 8361 - 8369 (2012)
The 2,2-bis(hydroxymethyl)propionic acid (BHP)-based generation 1 dendron with two palmitate tails (D1-C16) and the generation 2 dendron with four palmitate tails (D2-C16) were synthesized. The coupling of D1-C16 or D2-C16 with hyperbranched polyethylenimine (PEI) through the amidation reaction resulted in amphiphilic hyperbranched copolymers bearing a hyperbranched PEI core and a dendritic D1-C16 shell or dendritic D2-C16 shell. The structure of the obtained copolymers was verified through Fourier transform infrared (FTIR) and 1H nuclear magnetic resonance (NMR) characterization. Differential scanning calorimetry (DSC) measurement demonstrated that the existence of the branching units in the shell pronouncedly reduced the crystallinity of the hyperbranched copolymers, and the copolymers with less branched shells had a higher melting temperature and melting enthalpy. These novel amphiphilic hyperbranched copolymers could be used as nanocarriers to efficiently accommodate the hydrophilic guests, including Methyl Orange (MO), Congo Red (CR) and Direct Blue 15 (DB), into the hydrophilic amidated PEI core. Each nanocarrier with a branched shell could accommodate a much higher number of guests than the corresponding nanocarriers with linear shells, which indicated that the dendritic structure of the shell played a key role in significantly enhancing the encapsulation capacity of the nanocarriers. As far as the weight ratio of the encapsulated guests to the nanocarriers was concerned, the nanocarriers with branched shells could be modulated to have a similar encapsulation capacity for the small MO with a mono-sulfonate group, but a much superior encapsulation capacity for the large CR and DB guests with multi-sulfonate groups to the nanocarriers with linear shells.
Antitumor liposomes bearing a prodrug of combretastatin A-4 and a tetrasaccharide ligand of selectins
Sitnikov,Boldyrev,Moiseeva,Shavyrin,Beletskaya,Combes,Bovin,Fedorov,Vodovozova
, p. 2290 - 2296 (2010)
Therapeutic liposomes with an average diameter of 100 nm based on natural phospholipids (phosphatidylcholine and phosphatidylinositol) containing palmitoyl or oleoyl derivatives of the antimitotic agent combretastatin A-4 were constructed. The cytotoxicity of liposomes with the oleoyl derivative in the human breast cancer cell culture turned out to be only three times lower than that of combretastatin A-4, thus indicating the probability of facile intracellular hydrolysis of the prodrug. To achieve selective drug delivery to the tumor tissue in vivo, the diglyceride conjugate of the tetrasaccharide ligand of selectins, viz., Sialyl-Lewis X (SiaLeX, 2 mol.%) was incorporated into the liposomes. The SiaLeX-equipped liposomes loaded with the lipophilic prodrug showed a reliable inhibition of tumor growth on the model of spontaneous breast cancer in mice.
Association of adhesive spheres formed by hydrophobically end-capped PEO. 1. Influence of the presence of single end-capped PEO
Lafleche, Fabrice,Durand, Dominique,Nicolai, Taco
, p. 1331 - 1340 (2003)
Mixtures of poly(ethylene oxide) (PEO) end-capped on one or both ends with hexadecyl, but with the same hydrophilic-lypophilic balance, were studied using static and dynamic light scattering and dynamic mechanical measurements. In aqueous solution the mixtures form polymeric micelles with aggregation numbers that are independent of the fraction of difunctionalized PEO. Difunctionalized PEO bridges between two micelles, which leads to reversible association of the micelles. The phase behavior and the association of the micelles can be described by modeling the micelles as adhesive spheres with an adhesion parameter that depends on the fraction of difunctionalized PEO and the temperature. Above a given concentration the micelles percolate, leading to a strong increase of the viscosity and the high-frequency shear modulus. The viscosity has an Arrhenius temperature dependence with an activation energy close to that of the relaxation time that characterizes the decay of the shear modulus. At even higher concentrations an abrupt transition is observed that is characterized by the appearance of a second relaxation process with a very long relaxation time. The transition can be induced by small increases of the temperature or the concentration. The slow relaxation is attributed to restructuring of a solution of close packed micelles (e.g., hopping of micelles) while the fast relaxation, which is still visible at high concentrations, is attributed to the breakup of elastic bridges by the escape of end groups from the micelles.
Odd-even effect in a thiazole based organogelator: Understanding the interplay of non-covalent interactions on property and applications
Yadav, Priyanka,Ballabh, Amar
, p. 721 - 730 (2015)
New series of thiazole based amides, namely, 1e [N-(thiazol-2-yl)pentadecamide] to 1h [N-(thiazol-2-yl)stearamide], 2e [N-(4-methylthiazol-yl)pentadecamide] to 2h [N-(4-methylthiazol-yl)stearamide], 3e [N-(5-methylthiazol-yl)pentadecamide] to 3h [N-(5-methylthiazol-yl)stearamide] were synthesized, characterized and investigated for their gelation properties. Interestingly, out of three series of thiazole amides synthesized, two (1e-1h and 3e-3h) had displayed odd-even effect on gelation property with an increase in the methylene functional group of alkyl chain attached with thiazole moiety. The gelation-non-gelation of solvents was found to be more significant for the series of compounds 1e-1h, whereas a subtle effect was observed in the series of compounds 3e-3h. A single crystal study of non-gelator (2d) highlighted the crucial role of the methyl group and its position on the thiazole moiety in bringing about a change in supramolecular synthon from a robust cyclic N-H...N interaction to the combination of N-H...N and N-H...O interactions. Self-assembly of four molecules of 2d led to the formation of a zero-dimensional (0-D) hydrogen bonded network instead of a one-dimensional hydrogen bonded network observed in gelling compounds mediated by (methyl)C-H...N, C-H...O and van der Waals interaction. Various gelling agents (3e-3h) were used for the synthesis of nearly spherical silver and ZnO nanoparticles using a sol-gel method, through encapsulation and stabilization of nanoparticles in the gel network. Interestingly, the alkyl chain lengths of thiazole amides were found to affect the size of synthesized Ag and ZnO nanoparticles.
Sonication-Induced Halogenative Decarboxylation of Thiohydroxamic Esters
Dauben, William G.,Bridon, Dominique P.,Kowalczyk, Bruce A.
, p. 6101 - 6106 (1989)
The sonication of primary, secondary, and tertiary thiohydroxamic esters in CCl4 has led to their synthetic transformation to alkyl chlorides, bromides, or iodides.The high yields were comparable to the previous thermal-or photoinduced version of this same reaction.This radical reaction calls attention to the utility of ultrasound in production of trichloromethyl radical, which was concluded to initiate decomposition of the thiohydroxamic esters.
Tryptamine-derived alkaloids from Annonaceae exerting neurotrophin-like properties on primary dopaminergic neurons
Schmidt, Fanny,Douaron, Gael Le,Champy, Pierre,Amar, Majid,Seon-Meniel, Blandine,Raisman-Vozari, Rita,Figadere, Bruno
, p. 5103 - 5113 (2010)
N-fatty acyl tryptamines constitute a scarce group of natural compounds mainly encountered in Annonaceous plants. No biological activity was reported so far for these rare molecules. This study investigated the neurotrophic properties of these natural tryptaminic derivatives on dopaminergic (DA) neurons in primary mesencephalic cultures. A structure-activity relationships study led us to precise the role of a nitrogen atom into the aliphatic chain conferring to the compounds a combined neuroprotective and neuritogenic activity in the nanomolar range. The potent antioxidant activity of these natural products seems to be involved in part of their mechanism of action. This study provides the first description of natural neurotrophin mimetics present in Annonaceae extracts, and led to the biological characterization of compounds, which present a potential interest in neurodegenerative diseases such as Parkinson's disease.
Reducing the cost, smell, and toxicity of the Barton reductive decarboxylation: Chloroform as the hydrogen atom source
Ko, Eun Jung,Williams, Craig M.,Savage, G. Paul,Tsanaktsidis, John
, p. 1944 - 1947 (2011)
When used as solvent, chloroform was found to act as a hydrogen atom donor in Barton reductive decarboxylation reactions. Chloroform offers a substantial practical advantage over pre-existing hydrogen atom donors.
Quadruple helix formation of a photoresponsive peptide amphiphile and its light-triggered dissociation into single fibers
Muraoka, Takahiro,Cui, Honggang,Stupp, Samuel I.
, p. 2946 - 2947 (2008)
Using a peptide amphiphile having a bulky photolabile 2-nitrobenzyl group between the alkyl chain and the peptide segment, we demonstrated quadruple helical fiber formation and its dissociation into single fibrils in response to light. Putting the bulky g
Synthesis and characterization of allyl fatty acid derivatives as reactive coalescing agents for latexes
Barbosa, Joana V.,Oliveira, Fernanda,Moniz, Jorge,Magalhaes, Fernao D.,Bastos, Margarida M. S. M.
, p. 2215 - 2226 (2012)
This work evaluated the use of allyl fatty acid esters derived from vegetable oil (palmitic acid, soybean and sunflower oils) as reactive coalescing agents in a waterborne latex system. Allyl fatty acid derivatives (AFAD) from vegetable oils were synthesized by two different processes. The synthesis was monitored by IR-spectroscopy and the final product characterized by FT-IR, GC-MS, 1H and 13C NMR. The presence of conjugated double bonds in the aliphatic chain was confirmed, which is a determinant for the proposed autoxidative latexes drying mechanism. Each of the AFAD were subsequently added to a standard acrylic emulsion, in order to study its potential as reactive coalescing agent. The minimum film-forming temperature (MFT), glass transition temperature (Tg), drying time and rubbing resistance to solvents were evaluated. The results showed that, when added to water-borne acrylic resins, an AFAD acts as a non-volatile plasticizer capable of autoxidative crosslinking with itself. AOCS 2012.
