Epoxidation of Methyl Oleate and Subsequent Ring-Opening Catalyzed by Lipase from Candida sp. 99-125

2017 ◽  
Vol 120 (2) ◽  
pp. 1700257 ◽  
Author(s):  
Niuniu Lv ◽  
Wei He ◽  
Zheng Fang ◽  
Qin Sun ◽  
Chuanhong Qiu ◽  
...  
Keyword(s):  
Methyl Oleate ◽  
Ring Opening ◽  
Candida Sp

scholarly journals Biobased Aldehydes from Fatty Epoxides Through Thermal Cleavage of β-Hydroxy Hydroperoxides

2020 ◽  
Author(s):  
Thomas De Dios Miguel ◽  
Nam Duc Vu ◽  
Marc Lemaire ◽  
Nicolas Duguet
Keyword(s):  
Methyl Oleate ◽  
Ring Opening ◽  
Tungstic Acid ◽  
Flow Conditions ◽  
Large Excess ◽  
Molybdenum Catalysts ◽  
Thermal Cleavage ◽  
Optimized Conditions ◽  
C Nmr

The ring-opening of epoxidized methyl oleate by aqueous H<sub>2</sub>O<sub>2</sub> has been studied using tungsten and molybdenum catalysts to form the corresponding fatty b-hydroxy hydroperoxides. It was found that tungstic acid and phosphostungstic acid gave the highest selectivities (92-93%) towards the formation of the desired products, thus limiting the formation of the corresponding fatty 1,2-diols. The optimized conditions were applied to a range of fatty epoxides to give the corresponding fatty b-hydroxy hydroperoxides with 30-80% isolated yields (8 examples). These species were fully characterized by <sup>1</sup>H and <sup>13</sup>C NMR, HPLC-HRMS and their stability was studied by DSC. The thermal cleavage of the b-hydroxy hydroperoxide derived from methyl oleate was studied both in batch and flow conditions. It was found that the thermal cleavage in flow conditions gave the highest selectivity towards the formation of aldehydes with limited amounts of byproducts. The aldehydes were both formed with 68% GC yield and nonanal and methyl 9-oxononanoate were isolated with 57 and 55% yield, respectively. Advantageously, the overall process does not require large excess of H<sub>2</sub>O<sub>2</sub> and only generates water as a byproduct.

Ring opening of epoxidized methyl oleate using a novel acid-functionalized iron nanoparticle catalyst

2012 ◽  
Vol 14 (1) ◽  
pp. 136-142 ◽  
Author(s):  
B. Kollbe Ahn ◽  
Hongwang Wang ◽  
Shona Robinson ◽  
Tej B. Shrestha ◽  
Deryl L. Troyer ◽  
...  
Keyword(s):  
Methyl Oleate ◽  
Ring Opening ◽  
Iron Nanoparticle ◽  
Nanoparticle Catalyst

scholarly journals Biobased Aldehydes from Fatty Epoxides Through Thermal Cleavage of β-Hydroxy Hydroperoxides

2020 ◽  
Author(s):  
Thomas De Dios Miguel ◽  
Nam Duc Vu ◽  
Marc Lemaire ◽  
Nicolas Duguet
Keyword(s):  
Methyl Oleate ◽  
Ring Opening ◽  
Tungstic Acid ◽  
Flow Conditions ◽  
Large Excess ◽  
Molybdenum Catalysts ◽  
Thermal Cleavage ◽  
Optimized Conditions ◽  
C Nmr

The ring-opening of epoxidized methyl oleate by aqueous H<sub>2</sub>O<sub>2</sub> has been studied using tungsten and molybdenum catalysts to form the corresponding fatty b-hydroxy hydroperoxides. It was found that tungstic acid and phosphostungstic acid gave the highest selectivities (92-93%) towards the formation of the desired products, thus limiting the formation of the corresponding fatty 1,2-diols. The optimized conditions were applied to a range of fatty epoxides to give the corresponding fatty b-hydroxy hydroperoxides with 30-80% isolated yields (8 examples). These species were fully characterized by <sup>1</sup>H and <sup>13</sup>C NMR, HPLC-HRMS and their stability was studied by DSC. The thermal cleavage of the b-hydroxy hydroperoxide derived from methyl oleate was studied both in batch and flow conditions. It was found that the thermal cleavage in flow conditions gave the highest selectivity towards the formation of aldehydes with limited amounts of byproducts. The aldehydes were both formed with 68% GC yield and nonanal and methyl 9-oxononanoate were isolated with 57 and 55% yield, respectively. Advantageously, the overall process does not require large excess of H<sub>2</sub>O<sub>2</sub> and only generates water as a byproduct.

scholarly journals New Lipidyl-Cyclodextrins Obtained by Ring Opening of Methyl Oleate Epoxide Using Ball Milling

Biomolecules ◽  
2020 ◽  
Vol 10 (2) ◽  
pp. 339 ◽  
Author(s):  
Estefania Oliva ◽  
David Mathiron ◽  
Sébastien Rigaud ◽  
Eric Monflier ◽  
Emmanuel Sevin ◽  
...  
Keyword(s):  
Methyl Oleate ◽  
Ball Milling ◽  
Ring Opening ◽  
Fatty Ester ◽  
Water Soluble ◽  
Alternative Methods ◽  
Fatty Esters ◽  
Ring Opening Reaction ◽  
Vitro Model

Bearing grafts based on fatty esters derivatives, lipidyl-cyclodextrins (L-CDs) are compounds able to form water-soluble nano-objects. In this context, bicatenary biobased lipidic-cyclodextrins of low DS were easily synthesized from a fatty ester epoxide by means of alternative methods (ball-milling conditions, use of enzymes). The ring opening reaction of methyl oleate epoxide needs ball-milling and is highly specific of cyclodextrins in solventless conditions. L-CDs are thus composed of complex mixtures that were deciphered by an extensive structural analysis using mainly mass spectrometry and NMR spectroscopy. In addition, as part of their potential use as vectors of active drugs, these products were submitted to an integrity study on in vitro model of the blood-brain-barrier (BBB) and the intestinal epithelium. No toxicity has been observed, suggesting that applications for the vectorization of active ingredients can be expected.

scholarly journals Biobased Aldehydes from Fatty Epoxides Through Thermal Cleavage of β-Hydroxy Hydroperoxides

2020 ◽  
Author(s):  
Thomas De Dios Miguel ◽  
Nam Duc Vu ◽  
Marc Lemaire ◽  
Nicolas Duguet
Keyword(s):  
Methyl Oleate ◽  
Ring Opening ◽  
Tungstic Acid ◽  
Flow Conditions ◽  
Large Excess ◽  
Molybdenum Catalysts ◽  
Thermal Cleavage ◽  
Optimized Conditions ◽  
C Nmr

The ring-opening of epoxidized methyl oleate by aqueous H<sub>2</sub>O<sub>2</sub> has been studied using tungsten and molybdenum catalysts to form the corresponding fatty b-hydroxy hydroperoxides. It was found that tungstic acid and phosphostungstic acid gave the highest selectivities (92-93%) towards the formation of the desired products, thus limiting the formation of the corresponding fatty 1,2-diols. The optimized conditions were applied to a range of fatty epoxides to give the corresponding fatty b-hydroxy hydroperoxides with 30-80% isolated yields (8 examples). These species were fully characterized by <sup>1</sup>H and <sup>13</sup>C NMR, HPLC-HRMS and their stability was studied by DSC. The thermal cleavage of the b-hydroxy hydroperoxide derived from methyl oleate was studied both in batch and flow conditions. It was found that the thermal cleavage in flow conditions gave the highest selectivity towards the formation of aldehydes with limited amounts of byproducts. The aldehydes were both formed with 68% GC yield and nonanal and methyl 9-oxononanoate were isolated with 57 and 55% yield, respectively. Advantageously, the overall process does not require large excess of H<sub>2</sub>O<sub>2</sub> and only generates water as a byproduct.

Amino-functional polyethers: versatile, stimuli-responsive polymers

2020 ◽  
Vol 11 (24) ◽  
pp. 3940-3950 ◽  
Author(s):  
Patrick Verkoyen ◽  
Holger Frey
Keyword(s):  
Ring Opening ◽  
Review Article ◽  
Stimuli Responsive ◽  
New Class ◽  
Stimuli Responsive Polymers ◽  
Responsive Polymers

Amino-functional polyethers have emerged as a new class of “smart”, i.e. pH- and thermoresponsive materials. This review article summarizes the synthesis and applications of these materials, obtained from ring-opening of suitable epoxide monomers.

Infecção relacionada à assistência à saúde: Prevalência em Unidade de Terapia Intensiva Adulto

2020 ◽  
Vol 9 (9) ◽  
pp. e373997107
Author(s):  
Julyane Sampaio Trindade ◽  
Euzalice Gonçalves da Silva ◽  
Gleciane de Sousa Furtado ◽  
Dayara de Nazaré Rosa de Carvalho ◽  
Dandara de Fátima Ribeiro Bendelaque ◽  
...  
Keyword(s):  
Candida Sp ◽  
Terapia Intensiva

Objetivo: Verificar a prevalência de infecções relacionadas à assistência à saúde em pacientes adultos atendidos em Unidades de Terapia Intensiva. Metodologia: Estudo descritivo, epidemiológico, retrospectivo com abordagem quantitativa sobre a ocorrência de IRAS na unidade de terapia intensiva adulta, em um hospital das Forças Armadas de Belém, Estado do Pará. Resultado: Foram selecionados 91 pacientes, sendo a maioria idosa, de ambos os gêneros e proveniente da internação clínica/cirúrgica. Quanto ao perfil das infecções, houve predomínio das relacionadas ao sistema respiratório com (73,6%), seguindo com o trato urinário com (17,6%) e corrente sanguínea com (3,3%). Dentre os microrganismos identificados existe o predomínio de Acinetobacter baumanni (28,6%) e Candida SP (28,6%). Os antimicrobianos mais utilizados foram: Ceftriaxona (35,5%), Tazocin (32,3%) e Vancomicina (29,0%). Conclusão: Considera-se ter alcançado seu objetivo quanto a prevalência de IRAS na UTI da instituição pesquisada, possibilitando a equipe de saúde elencar estratégicas e medidas de prevenção com maior especificidade e direcionamento voltado à realidade local. Este estudo contribuiu para o conhecimento sobre os dados de prevalência das IRAS no ambiente hospitalar tornando evidente a necessidade de maior vigilância epidemiológica das infecções em Unidade de Terapia Intensiva.

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