Baeyer Villiger Oxidation
Mostrando 1-12 de 16 artigos, teses e dissertações.
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1. Investigação da seletividade de mono-oxigenases frente a substratos orgânicos de boro ou de selênio / Investigation on selectivity of mono-oxigenases in the presence of boron-containing or seleniun-containing organic compounds
Neste trabalho foi avaliada a seletividade (quimio ou enantiosseletividade) de quatro enzimas Baeyer-Villiger mono-oxigenases (BVMOs: PAMO, PAMO M446G, HAPMO e CHMO) frente a substratos contendo boro ou selênio. Inicialmente uma série de boro-acetofenonas foram submetidas à bio-oxidação catalisada por estas BVMOs. A enzima CHMO mostrou quimiosseletivida
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 25/05/2012
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2. Estudo do potencial enzimático de micro-organismos endofíticos para a biotransformação de produtos naturais e análogos sintéticos / Study of endophitic microorganisms potential on the biotransformation of natural products
The endophytic microorganisms Penicillium griseoroseum, Penicillium brasilianum, Aspergillus flavus e Aspergillus aculeatus have shown to be very efficient in order to perform the most diferenciated biotransformation reactions. The fungi Penicillium griseoroseum has presented an elevated desmethylation selectivity of the caffeine substrate besides the desmet
Publicado em: 2009
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3. Oxidação Baeyer-Villiger de cicloexanona com peroxido de hidrogenio catalisada por alumina / Alumina-catalyzed-Villiger oxidation of cyclohexanone with hydrogen peroxide
Two aluminas, one comercial (Fluka) and the other obtained by sol-gel methods, were used as catalysts for the Baeyer-Villiger oxidation using cyclohexanone as substrate and hydrogen peroxide as oxidant. The catalysts were characterized by X-ray diffraction and thermogravimetric analysis and the oxidation products were analysed by gas chromatography and H and
Publicado em: 2007
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4. Biotransformações de cetonas aromáticas e cíclicas promovidas por fungos / Biotransformations of cyclic and aromatic ketones by fungi
In this work, we evaluated the enzymatic potential of different Aspergillus strains, through the biotransformations of two substrates: 2- and 4-methylcyclohexanone (1a e 1b). All the strains employed showed alcohol dehydrogenase and Baeyer-Villiger monooxygenase (CPMO and CHMO) activities. These enzymes can perform ketone biorreduction and oxidation. Using t
Publicado em: 2005
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5. Conformational analysis and electronic interaction study of some ortho-substituted alpha-ethylsulfonylacetophenones; and the oxidative rearrangement study of some ortho-substituted alpha-ethylthioacetophenones / Análise conformacional e estudo das interações eletrônicas em alfa-etilsulfonilacetofenonas-orto-substituídas e o estudo do rearranjo oxidativo de alfa-etiltioacetofenonas-orto-substituídas
The first part of this thesis reports the conformational study of some -ortho-substituted α-ethylsulfonylacetophenones o-X-PhC(O)CH2SO2Et (X= OMe 1, Me 2, F 3, Cl 4, Br 5 e NO2 6) through the analysis of the carbonyl stretching IR band in solvents of increasing polarity supported by HF/6-31G** ab initio computations. The good match between IR frequencie
Publicado em: 2005
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6. Estudos visando a sÃntese de 7-hidroxi-6,11-ciclofarnes-3(15)-EN-2-ONA
In this work we describe alternative synthetic routes toward the preparation of a new α,β-unsaturated sesquiterpene with antibacterial activity isolated from Premma oligotricha. Baeyer-Villiger oxidation of trimethyldecalone (51a) yielded the corresponding lactone intermediate (52a) which was submitted to several sulfophenyl- and hydroxymethylation
Publicado em: 2002
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7. Zr[bis(salicylidene)ethylenediaminato]-mediated Baeyer–Villiger oxidation: Stereospecific synthesis of abnormal and normal lactones
Baeyer–Villiger oxidation of racemic bicyclic cyclobutanones with Zr[bis(salicylidene)ethylenediaminato] (salen) complex 1 as catalyst in the presence of a urea-hydrogen peroxide adduct was found to proceed enantiospecifically. The enantiotopos selection in the oxidation was governed primarily by the Zr(salen) catalyst, although migratory aptitude (methine
National Academy of Sciences.
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8. Arabidopsis CYP85A2, a Cytochrome P450, Mediates the Baeyer-Villiger Oxidation of Castasterone to Brassinolide in Brassinosteroid Biosynthesis
The conversion of castasterone (CS) to brassinolide (BL), a Baeyer-Villiger oxidation, represents the final and rate-limiting step in the biosynthesis of BL in plants. Heterologously expressed Arabidopsis thaliana CYP85A2 in yeast mediated the conversion of CS to BL as well as the C-6 oxidation of brassinosteroids (BRs). This indicated that CYP85A2 is a bifu
American Society of Plant Biologists.
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9. Conversion of 4-Hydroxyacetophenone into 4-Phenyl Acetate by a Flavin Adenine Dinucleotide-Containing Baeyer-Villiger-Type Monooxygenase
An arylketone monooxygenase was purified from Pseudomonas putida JD1 by ion exchange and affinity chromatography. It had the characteristics of a Baeyer-Villiger-type monooxygenase and converted its substrate, 4-hydroxyacetophenone, into 4-hydroxyphenyl acetate with the consumption of one molecule of oxygen and oxidation of one molecule of NADPH per molecule
American Society for Microbiology.
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10. Substrate Specificity and Enantioselectivity of 4-Hydroxyacetophenone Monooxygenase
The 4-hydroxyacetophenone monooxygenase (HAPMO) from Pseudomonas fluorescens ACB catalyzes NADPH- and oxygen-dependent Baeyer-Villiger oxidation of 4-hydroxyacetophenone to the corresponding acetate ester. Using the purified enzyme from recombinant Escherichia coli, we found that a broad range of carbonylic compounds that are structurally more or less simila
American Society for Microbiology.
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11. Microbial oxidation of oleic acid.
Resting cells of Saccharomyces cerevisiae (baker's yeast, type II; Sigma) were used to convert oleic acid into 10-hydroxyoctadecanoic acid with a 45% yield. Nocardia aurantia (ATCC 12674), Nocardia sp. (NRRL 5646), and Mycobacterium fortuitum (UI 53378) all converted oleic acid into 10-oxo-octadecanoic acid with 65, 55, and 80% yields, respectively. Structur
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12. Cloning and Characterization of a Gene Cluster for Cyclododecanone Oxidation in Rhodococcus ruber SC1
Biological oxidation of cyclic ketones normally results in formation of the corresponding dicarboxylic acids, which are further metabolized in the cell. Rhodococcus ruber strain SC1 was isolated from an industrial wastewater bioreactor that was able to utilize cyclododecanone as the sole carbon source. A reverse genetic approach was used to isolate a 10-kb g
American Society for Microbiology.