- Lipase-catalyzed chemoselective N-acylation of amino-sugar derivatives in hydrophobic solvent: Acid-amine ion-pair effects
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Enzymatic N-acylation of N-methyl-glucamine (1-deoxy-1-methylamino-D-glucitol) in hexane using lipase from Rhizomucor miehei (Lipozyme) is described. N-methyl-glucamine was solubilized by oleic acid addition which resulted in the formation of an ion-pair between acid and amine function. This ion-pair, identified by Infra-Red spectroscopy, is essential for amide or ester synthesis. Its stability in hexane was also found to be the limiting factor of reaction yield which never exceeded 50% of acid conversion. The chemoselectivity of the reaction between oleic acid and N-methyl-glucamine towards amide or ester synthesis was under the control of acid/amine ratio. This is the first report showing the key role of substrate ionic state shen operating enzyme catalysis in non-conventional media.
- Maugard, Thierry,Remaud-Simeon, Magali,Petre, Dominique,Monsan, Pierre
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- Enzymatic synthesis of glycamide surfactants by amidification reaction
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The condensation of a secondary amine (N-methyl-glucamine) with oleic acid was selected as a reaction model to study the production of glycamide surfactants by enzymatic amidification. Reactions catalyzed by immobilized lipase from Candida antarctica were carried out in 2-methyl-2-butanol. The acido-basic conditions (through the N-methyl glucamine / oleic acid ratio) control the chemoselectivity of the reaction allowing the synthesis of either amide, ester or amide-ester. At 90°C and with a N-methyl-glucamine I acid ratio of 1, a 100% conversion yield with 97% of amide synthesis was obtained in less than 50 hours. The process was applied to the preparation of a range of amides using various amines and acyl donors. This process is the first that describes successful amide bond synthesis from a hydroxylated secondary amine and fatty acid or fatty acid ester.
- Maugard, Thierry,Remaud-Simeon, Magali,Petre, Dominique,Monsan, Pierre
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- ACOUSTICALLY-ACTIVATED COSMETIC HYDROGELS
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A composition that includes an activatable aggregate is described herein. The aggregate has a core and a shell. In some embodiments, when the aggregate is exposed to acoustic energy, the core of the aggregate includes a hydrogel that is capable of absorbing a relatively large amount of water. The core of the aggregate is covalently bound to a shell of linear aliphatic moieties. The aggregate is synthesized to minimize the amount of water in the core, prior to exposure to acoustic energy. Methods of hydrating using the compositions are also provided.
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Page/Page column 35; 36; 37
(2016/07/27)
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- Use Of N-Methyl-N-Acylglucamines As Solubilizers
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The invention relates to the use of N-methyl-N-C8-C14-acylglucamines as solubilizers in cosmetic preparations. The invention further relates to clear lotions for the preparation of wet wipes, comprising a) 0.1 to 5.0 wt.-% of the N-methyl-N—C8-C14-acylglucamines, b) 0.05 to 5% of one or more water-insoluble or only partially water-soluble anti-microbial agents, c) 0 to 5 wt.-% of one or more oils, d) 85 to 99.85 wt.-% of water, e) 0 to 5 wt.-% of surfactants, and f) 0 to 5 wt.-% of additional auxiliaries and additives.
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Paragraph 0070
(2015/05/26)
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