- Mammalian exocrine secretions. XIV: Constituents of preorbital secretion of steenbok, Raphicerus campestris
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In a study aimed primarily at qualitative comparison of the organic constituents of the preorbital secretion of the steenbok, Raphicerus campestris, with those previously found in the preorbital secretion of the grysbok, R. melanotis, 109 compounds were identified in the secretion of the steenbok. Although the secretions from the two antelope are similar in that they are mostly long-chain, unbranched, saturated and unsaturated alcohols and various derivatives of these alcohols, only 22 of the identified compounds are present in both secretions. This is a small percentage of the more than 260 compounds present in the secretion of the steenbok, which is much more complex than that of the grysbok.
- Burger,Greyling,Spies
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- Mammalian exocrine secretions. XII: Constituents of interdigital secretions of bontebok, Damaliscus dorcas dorcas, and blesbok, D. d. phillipsi
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In addition to the nine compounds identified in the interdigital secretion of the bontebok, Damaliscus dorcas dorcas, in a previous study, 76 compounds belonging to different compound types, were identified in the interdigital secretions of the bontebok and the blesbok, D. d. phillipsi. These compounds include alkanes, alcohols, aldehydes, ketones, fatty acids, terpenoids, γ-lactones, an isopropyl ester, long-chain hydroxyesters, 2- substituted pyridines, phenols, steroids, and dimethylsulfone. No qualitative differences were found between secretions from the two sexes or from animals from different habitats. Although no attempt was made to correlate territorial behavior or other behavioral phenomena with the qualitative composition of interdigital secretions from individual animals, available information seems to indicate that quantitative differences probably do not have a major semiochemical function. Only two species of bacteria, Bacillus brevis and Planococcus citreus, were found in the interdigital pouches of male and female members of the two subspecies, regardless of the habitat of the animals. B. brevis synthesized, among other unidentified constituents, (Z)-3-penten-2-ol, 2-hexanone, 2-octanone, 2-nonanone, tetradecanoic acid, pentadecanoic acid, heptadecanoic acid, octadecanoic acid, (Z)-9-hexadecenoic acid, and isopropyl hexadecanoate in vitro, while P. citreus produced, among others, the γ-lactones dodecan-4-olide and (Z)-6-dodecen-4-olide, which is one of the major constituents of the interdigital secretions of both subspecies. Some components of the interdigital secretions are not present in the interdigital glandular tissue, and the possibility is discussed that these compounds could be produced by microbiological activity in the interdigital pouch.
- Burger,Nell,Spies,Le Roux,Bigalke,Brand
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- Method for synthesis of long-chain fatty acid ester derivative
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The invention relates to a method for synthesis of a long-chain fatty acid ester derivative. Specifically, a hydrochloride of glycine methyl ester or glycine ethyl ester is used as a catalyst to catalyze the esterification reaction of long-chain fatty acid. The method includes: subjecting alcohol and long-chain fatty acid to esterification reaction under the action of the catalyst at certain temperature condition, then conducting extraction and precipitation with ethyl acetate, performing flushing with a sodium chloride aqueous solution for purification. A hydrochloride of glycine methyl esteror glycine ethyl ester is adopted as the catalyst, which belongs to a green catalyst, is the development trend of modern chemistry, has the characteristics of no corrosion to the reaction kettle, lowprice, no toxicity and the like, and is suitable for use as a catalyst to produce palmitate and laurate perfume raw materials.
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Paragraph 0029-0030
(2020/01/12)
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- Method for catalytically synthesizing isopropyl palmitate by using silica gel immobilized multi-sulfonic functionalized ionic liquid
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The invention discloses a method for catalytically synthesizing isopropyl palmitate by using a silica gel immobilized polysulfonic functionalized ionic liquid, and belongs to the technical field of synthesis of ester compounds in organic chemistry. The invention solves the technical problems of preparing isopropyl palmitate by using conventional methods such as an acyl chloride method, a direct esterification method and the like in the prior art, and overcomes the defects that the recovery rate of an ionic liquid is not high and the price of the ionic liquid is high in actual use. According tothe invention, palmitic acid and isopropyl alcohol are used as raw materials, a silica gel immobilized polysulfonic functionalized ionic liquid is used as a catalyst, and isopropyl palmitate is catalytically synthesized through direct esterification under a heating condition. The method has the advantages of simple process, mild conditions, simple and convenient post-treatment, low cost, and goodcatalytic effect; the obtained product has no color or low color and has high quality; the reaction esterification rate can reach 95-98%; and the catalysis activity is still good after the catalyst is recycled for multiple times.
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Paragraph 0033-0047
(2019/01/06)
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- Preparation of phenol- or thiophenyl-sulfonic acid functionalized solid acids
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Some aryl sulfonic acid-functionalized solids were prepared by a new method. The catalytic activities of esterification by the prepared aryl sulfonic acid-functionalized solids were also tested.
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Page/Page column 10; 11
(2015/07/02)
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- Zirconium-containing metal organic frameworks as solid acid catalysts for the esterification of free fatty acids: Synthesis of biodiesel and other compounds of interest
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Zr-containing metal organic frameworks (MOFs) formed by terephthalate (UiO-66) and 2-aminoterephthalate ligands (UiO-66-NH2) are active and stable catalysts for the acid catalyzed esterification of various saturated and unsaturated fatty acids with MeOH and EtOH, with activities comparable (in some cases superior) to other solid acid catalysts previously reported in literature. Besides the formation of the corresponding fatty acid alkyl esters as biodiesel compounds (FAMEs and FAEEs), esterification of biomass-derived fatty acids with other alcohols catalyzed by the Zr-MOFs allows preparing other compounds of interest, such as oleyl oleate or isopropyl palmitate, with good yields under mild conditions.
- Cirujano,Corma,Llabrés I Xamena
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p. 213 - 220
(2015/02/19)
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- Efficient microwave-assisted esterification reaction employing methanesulfonic acid supported on alumina as catalyst
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A rapid and efficient protocol assisted by microwave irradiation for the synthesis of esters using methanesulfonic acid (CH3SO3H) supported on Al2O3 (AMA) as catalyst and free of solvent is described. The products were obtained in good yields and purity, with reduced reaction time, and the process is simple and environmentally benign. Copyright
- Fabian, Lucas,Gomez, Matias,Kuran, Juan A. Caturelli,Moltrasio, Graciela,Moglioni, Albertina
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p. 2386 - 2392
(2014/07/22)
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- Zn(OTf)2-promoted chemoselective esterification of hydroxyl group bearing carboxylic acids
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Selective esterification of aliphatic and aromatic carboxylic acids with various alcohols is studied using triphenylphosphine, I2, and a catalytic amount of Zn(OTf)2. Use of this catalyst allows the formation of esters at a faster rate with good to excellent yield by activating the in situ generated acyloxyphosphonium ion intermediate. During the esterification process, both their aromatic and aliphatic hydroxyl groups are fully preserved from transesterification. The results show that the bulkiness and the reactivity of this doubly activated intermediate III control the selectivity and the rate of the reaction, respectively. The method is also useful for direct amidation reactions.
- Mamidi, Narsimha,Manna, Debasis
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p. 2386 - 2396
(2013/05/21)
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- Synthesis and evaluation of different fatty acid esters formulated into Precirol ATO-based lipid nanoparticles as vehicles for topical delivery
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A series of isopropyl fatty esters having different chain length (C 13-C23) were synthesized and formulated in lipid nanoparticles based on Precirol ATO to evaluate their effect on the physicochemical properties of these latter. Moreover, drug loading and skin permeation of Econazole nitrate, chosen as a lipophilic model drug, were evaluated as well. The obtained nanosystems, prepared by high shear homogenization method, had a mean diameter ranging from 180 to 280 nm and showed an encapsulation efficiency of about 100%. Ex vivo permeation results demonstrated a parabolic correlation between permeation effect and chain length of the fatty esters present in the lipid nanoparticles formulated in hydrophilic gels. The maximum flux of drug was observed for the nanoparticles containing esters with 17 and 19 carbon atoms, suggesting that these formulations may constitute a potential carrier for topical delivery of econazole nitrate.
- Sanna, Vanna,Mariani, Alberto,Caria, Giuseppe,Sechi, Mario
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experimental part
p. 680 - 684
(2009/12/26)
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- An eco-friendly method for the synthesis of aryl and alkyl esters of carboxylic acids using acid activated Indian bentonite
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Esterification of various carboxylic acids with phenol and alcohols has been achieved using acid activated Indian bentonite (AAIB) as catalyst. The catalyst is versatile, and the reaction is found to work well for primary, secondary and tertiary alcohols. The yields are very good under specific reaction conditions.
- Vijayakumar,Iyengar, Pushpa,Nagendrappa, Gopalpur,Prakash, B. S. Jai
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p. 922 - 925
(2007/10/03)
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- How is chemical interesterification initiated: Nucleophilic substitution or α-proton abstraction?
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Esters of carboxylic acids including 2-methylhexanoic, 2-methylbutyric, 2,2-dimethyl-4-pentenoic, palmitic, and oleic acids were tested as substrates in methoxide-catalyzed interesterification and transesterification. The aliphatic acid esters participated in the ester-ester interchange upon addition of catalytic sodium methoxide. Their isopropyl esters also produced methyl esters on heating with sodium methoxide. The esters of dimethyl-substituted acids did not participate in the ester-ester interchange. Their isopropyl esters did not react with methoxide to produce methyl esters. However, upon addition of methanol with sodium methoxide, their methyl esters were produced. These results indicate that the first step in interesterification is possibly that methoxide abstracts the α-hydrogen of an ester to form a carbanion. Interesterification is then likely completed via a Claisen condensation mechanism involving the β-keto ester anion as the active intermediate. The β-keto ester anion contains positively charged ketone and acyl carbons that are active sites for nucleophilic attack by anions such as methoxide and glycerinate, which would produce a methyl ester or rearrange acyls randomly. On the other hand, transesterification is a nucleophilic substitution by methoxide at the acyl carbon in the presence of methanol.
- Liu, Linsen
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p. 331 - 337
(2007/10/03)
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- Method for the esterification of a fatty acid
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The method for the esterification of a fatty acid F is carried out in a column with a packing. In addition to functioning as a catalytic reactor, the packing functions as a stripping section. A heteregenous catalysis of a fatty acid is carried out with an alcohol used in the same molar ratio or in excess. A gaseous alcohol-rich counter-flow is produced in a sump of the column by vaporisation. Water is removed from the reaction zone by means of the counter-flow acting as a stripping gas. The loaded stripping gas is at least partially liquefied at the head of the column. The head product is separated into a water-rich fraction as well as an alcohol-rich fraction. The alcohol-rich fraction is returned to the process as a starting material for the esterification and for the production of the stripping gas.
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- Pharmaceutical compositions for transdermal administration of anti-inflammatory agents
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The invention concerns a pharmaceutical composition for transdermal administration comprising: a polymeric release matrix capable of forming a soft film after drying, selected among cellulose polymers or copolymers, said matrix being present at a concentration not exceeding 6% of the composition weight; an active principle selected among the group of non-steroid anti-inflammatory agents comprising at least a metal carboxylic or carboxitate group; a transcutaneous absorption promoter of the active principle; water; and at least a physiologically acceptable non-aqueous solvent capable of dissolving the release matrix, the active principle and transcutaneous absorption promoter and to be rapidly eliminated by evaporation in contact with the skin.
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- Esters, retroesters, and a retroamide of palmitic acid: Pool for the first selective inhibitors of N-palmitoylethanolamine-selective acid amidase
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Cyclohexyl hexadecanoate, hexadecyl propionate, and N-(3-hydroxypropionyl)pentadecanamide, respectively ester, retroester, and retroamide derivatives of N-palmitoylethanolamine, represent the first selective inhibitors of "N-palmitoylethanolamine hydrolase" described so far. These compounds are devoid of affinity for CB1 and CB 2 receptors and characterized by high percentages of inhibition of N-palmitoylethanolamine-selective acid amidase (84.0, 70.5, and 76.7% inhibition at 100 μM, respectively) with much lower inhibitory effect on either fatty acid amide hydrolase or the uptake of anandamide.
- Vandevoorde, Séverine,Tsuboi, Kazuhito,Ueda, Natsuo,Jonsson, Kent-Olov,Fowler, Christopher J.,Lambert, Didier M.
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p. 4373 - 4376
(2007/10/03)
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- Lip treatment composition
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A lip-treatment composition for topical application to the lips comprising a base comprising oil, water and a structurant, and at least one active component active with regard to the lips, gums, teeth, throat, or oral mucosa.
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- A CONVENIENT METHOD OF ESTERIFICATION OF FATTY ACIDS. PREPARATION OF ALKYL ESTERS, STEROL ESTERS, WAX ESTERS AND TRIACYLGLYCEROLS
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A quick and mild, one-pot method of esterification of fatty acids with pripary, secondary and tertiary alcohols as well as with fatty alcohols, sterols and glycerol is proposed via the acyl bromides formed in situ.
- Saroja, M.,Kaimal, T. N. B.
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p. 1423 - 1430
(2007/10/02)
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