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Tytuł:
Prolina – pospolity aminokwas wyjątkowy katalizator. Część I, Biosynteza proliny. Wewnątrzcząsteczkowa kondensacja aldolowa
Proline as a common amino acid and an exceptional catalyst. Part I, Proline biosynthesis. Intramolecular aldol reaction
Autorzy:
Wróblewski, M.
Kołodziejska, R.
Studzińska, R.
Karczmarska-Wódzka, A.
Dramiński, M.
Powiązania:
https://bibliotekanauki.pl/articles/172473.pdf
Data publikacji:
2013
Wydawca:
Polskie Towarzystwo Chemiczne
Tematy:
biosynteza proliny
mechanizm kondensacji aldolowej
wewnątrzcząsteczkowa reakcja aldolowa
proline biosynthesis
mechanism of aldol reaction
intramolecular aldol reaction
Opis:
In asymmetric synthesis of organic compounds more effective solutions are being looked for which will result in higher yield(s) of product(s) and their high enantioselectivity [1]. One of such solutions is an use of a multilevel and cheap catalyst. Proline used as a catalyst is a substance of natural origin which was synthetically obtained by Willstätter who was carrying out research on hygric acid (Scheme 1) [10]. The cells of many organisms have a suitable enzymatic system essential for proline biosynthesis [15]. So far, three proline biosynthesis pathways have been described: from glutamate (Scheme 3 and 4), ornithine (Scheme 5 and 6), and arginine (Scheme 7) [16–28]. Proline which is obtained as a result of biosynthesis or supplementation is a substrate for many proteins. Characteristic and significant content (about 23%) of this amino acid was observed in collage. In cells proline can play an important role of osmoregulator [31–35] – a protective substance regulating the activity of such enzymes as catalase and peroxidase [36]. Proline as a secondary amine shows exceptional nucleophilicity facilitating imine and enamine formation. Used as a catalyst in aldol reaction makes with substrates like imine or enamine transition state imitating the activity of naturally occurring enzymes for this type of reaction, that is aldolases. In their research Hajos and Parrish, and Eder, Sauer and Wiechert used proline in intramolecular aldol reaction obtaining proper enones (Scheme 9) [60–62]. The process of intramolecular aldol reaction was used for a separation of racemic mixture of diketones (Scheme 10) [63, 64], cyclization of ortho-substituted aromatic aldehydes and ketones (Scheme 11) [65], synthesis of cyclic diketones (Scheme 13) [68] and domino reaction to obtain substituted cyclohexanones from beta-diketones and unsaturated ketones (Scheme 14) [69].
Źródło:
Wiadomości Chemiczne; 2013, 67, 9-10; 801-818
0043-5104
2300-0295
Pojawia się w:
Wiadomości Chemiczne
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Biomarkers in canine inflammatory bowel disease diagnostics
Autorzy:
Wdowiak, M.
Rychlik, A.
Kolodziejska-Sawerska, A.
Powiązania:
https://bibliotekanauki.pl/articles/31118.pdf
Data publikacji:
2013
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Opis:
Canine inflammatory bowel disease (IBD) is a heterogeneous group of chronic gastrointestinal disorders. The etiology, similar to human IBD, remains unknown. Canine IBD is diagnosed by exclusion, which is a long, time and money-consuming process due to the need of elimination of other diseases presenting with similar symptoms. Therefore, a search for a specific and sensitive marker is needed to overcome these difficulties. The article is divided into 3 sections presenting up-to-date information about laboratory markers, immunohistochemical markers and changes in the neurochemical coding of the enteric nervous system, concentrating on their usefulness and future applications. Data concerning laboratory and immunohistochemical markers is based mainly on canine IBD, while the neuroimmunohistochemistry section presents knowledge from human IBD due to the lack of such studies in veterinary medicine.
Źródło:
Polish Journal of Veterinary Sciences; 2013, 16, 3
1505-1773
Pojawia się w:
Polish Journal of Veterinary Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Modulation of specific biochemical blood parameters by helminth infection in laboratory Beagle dogs
Autorzy:
Szweda, M.
Szarek, J.
Babinska, I.
Sokol, R.
Ras-Norynska, M.
Kolodziejska-Sawerska, A.
Mecik-Kronenberg, T.
Powiązania:
https://bibliotekanauki.pl/articles/31110.pdf
Data publikacji:
2012
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Opis:
The objective of this study was to examine the independent effect of helminths infection on biochemical blood parameters in Beagles intended for laboratory use which may contribute to a change of experimental results. As a result of research, the authors confirmed the negative effect of helminth invasion on the metabolism of the liver and kidney in laboratory dogs. Stool samples from thirty Beagle puppies were examined for parasites before the puppies were moved to the animal facility, and all were dewormed with Vetminth paste on the day they were moved. Stool examination was performed three more times and animals were given Drontal Plus flavor (Bayer) and Baycox 5% (Bayer). A fourth parasitological examination revealed no intestinal parasites in the feces. Three blood biochemical tests were performed. Experimental results clearly indicate the significant impact of intestinal parasites in dogs used in experiments.
Źródło:
Polish Journal of Veterinary Sciences; 2012, 15, 2
1505-1773
Pojawia się w:
Polish Journal of Veterinary Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The impact of temperament type on the occurrence of stereotypic behaviour in chinchillas
Wpływ typu usposobienia na występowanie zachowań stereotypowych u szynszyli
Autorzy:
Święcicka, N.
Bogucki, M.
Kołodziejska-Sawerska, A.
Powiązania:
https://bibliotekanauki.pl/articles/29433600.pdf
Data publikacji:
2022
Wydawca:
Zachodniopomorski Uniwersytet Technologiczny w Szczecinie. Wydawnictwo Uczelniane ZUT w Szczecinie
Tematy:
chinchilla
character
temperament
compulsive behaviour
occurrence
Źródło:
Acta Scientiarum Polonorum. Zootechnica; 2022, 21, 2; 19-26
1644-0714
Pojawia się w:
Acta Scientiarum Polonorum. Zootechnica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Uses of tree saps in northern and eastern parts of Europe
Autorzy:
Svanberg, I.
Soukand, R.
Luczaj, L.
Kalle, R.
Zyryanova, O.
Denes, A.
Papp, N.
Nedelcheva, A.
Seskauskaite, D.
Kolodziejska-Degorska, I.
Kolosova, V.
Powiązania:
https://bibliotekanauki.pl/articles/57637.pdf
Data publikacji:
2012
Wydawca:
Polskie Towarzystwo Botaniczne
Źródło:
Acta Societatis Botanicorum Poloniae; 2012, 81, 4
0001-6977
2083-9480
Pojawia się w:
Acta Societatis Botanicorum Poloniae
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Prolina : pospolity aminokwas wyjątkowy katalizator. Część III, Reakcja Mannicha
Proline as a common amino acid and an exceptional catalyst. Part III, Mannich reaction
Autorzy:
Studzińska, R.
Karczmarska-Wódzka, A.
Wróblewski, M.
Kołodziejska, R.
Dramiński, M.
Powiązania:
https://bibliotekanauki.pl/articles/172649.pdf
Data publikacji:
2014
Wydawca:
Polskie Towarzystwo Chemiczne
Tematy:
prolina
reakcja Mannicha
synteza asymetryczna
proline
Mannich reaction
asymmetric synthesis
Opis:
Mannich reaction occuring among ketone, aldehyde, and amine is one of the ways of a synthesis of biologically active compounds. Reactions of this type were carried out in the presence of different catalysts [3–10], however in recent years a lot of attention has been paid to enantioselective Mannich reaction catalyzed with proline. Such reactions were carried out with the use of different compounds containing carbonyl group and the most frequently used amine was p-anisidine. The advantage of the use of p-anisidine is a possibility of conducting the direct Mannich reaction (Scheme 3). In this way β-amino ketones (Tab. 1, 2, 4) [15, 18–20, 23, 24], α-hydroxy-β-amino ketones (Tab. 3) [15, 22], and β-amino alcohols (Tab. 5, 6) [25, 26] were obtained. A possibility of syntheses of β-amino sugars and α-amino acids with their derivatives (Tab. 7) [28, 29] is worth noticing. In a great number of described reactions, the products were obtained with satisfactory yield and enantiomeric excess. Taking into consideration the difficulty of a removal of p-hydroxyphenyl group which protects amine group in the resulting products, the attempts of using different amine compounds in Mannich reactions catalyzed with proline were undertaken. The use of amines blocked by tert-butoxycarbonyl group (Boc) enabled to obtain the products with high yield and ee values (Tab. 12–15) [35–38]. However in the case of the use of Boc the reaction must be carried out in an indirect way (it is necessary to prepare imine blocked by Boc earlier).
Źródło:
Wiadomości Chemiczne; 2014, 68, 1-2; 21-48
0043-5104
2300-0295
Pojawia się w:
Wiadomości Chemiczne
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A correlation between the Canine Inflammatory Bowel Disease Activity Index score and the histopathological evaluation of the small intestinal mucosa in canine inflammatory bowel disease
Autorzy:
Rychlik, A.
Nieradka, R.
Kander, M.
Nowicki, M.
Wdowiak, M.
Kolodziejska-Sawerska, A.
Powiązania:
https://bibliotekanauki.pl/articles/31320.pdf
Data publikacji:
2012
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Opis:
The aim of this study was to assess the degree of correlation between the intensity of clinical symptoms and the macroscopic and histopathological evaluation of the small intestinal mucous membrane in dogs. The results point to a statistically significant correlation between the values of the CIBDAI index and the histopathological assessment of the duodenum mucous membrane in patients with minor and moderate intensity of the disease. The lowest correlation coefficient was obtained for the indicator comparing macroscopic and histopathological evaluations. A positive correlation between the CIBDAI score and the histopathological index offers a base for applying it in the monitoring and treatment of mild, moderate and severe cases of canine inflammatory bowel disease.
Źródło:
Polish Journal of Veterinary Sciences; 2012, 15, 2
1505-1773
Pojawia się w:
Polish Journal of Veterinary Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Clinical, endoscopic and histopathological evaluation of the efficacy of budesonide in the treatment of inflammatory bowel disease in dogs
Autorzy:
Rychlik, A.
Kolodziejska-Sawerska, A.
Nowicki, M.
Szweda, M.
Powiązania:
https://bibliotekanauki.pl/articles/30824.pdf
Data publikacji:
2016
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Opis:
This study evaluates the efficacy of budesonide in the treatment of inflammatory bowel disease (IBD) in dogs based on the results of clinical, endoscopic and histopathological examinations. The severity of clinical symptoms was assessed based on CIBDAI scores, and macroscopic and histopathological changes were described in accordance with the recommendations of the WSAVA Gastrointestinal Standardization Group for 2008. The results of the experiment revealed that budesonide does not offer effective treatment for canine IBD. The tested drug failed to alleviate the clinical symptoms of disease, lower CIBDAI scores, or improve the macroscopic appearance of intestinal mucosa. The effectiveness of budesonide was most highly evaluated in the histopathological picture of duodenal, jejunal and colonic mucosa.
Źródło:
Polish Journal of Veterinary Sciences; 2016, 19, 1
1505-1773
Pojawia się w:
Polish Journal of Veterinary Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Antimicrobial properties of chitosan solutions, chitosan films and gelatin-chitosan films
Przeciwdrobnoustrojowe właściwości roztworów chitozanowych, folii chitozanowych i żelatynowo-chitozanowych
Autorzy:
Malinowska-Pańczyk, E.
Staroszczyk, H.
Gottfried, K.
Kołodziejska, I.
Wojtasz-Pająk, A.
Powiązania:
https://bibliotekanauki.pl/articles/947459.pdf
Data publikacji:
2015
Wydawca:
Sieć Badawcza Łukasiewicz - Instytut Chemii Przemysłowej
Tematy:
chitosan
chitosan film
gelatin-chitosan film
antimicrobial films
chitozan
folia chitozanowa
folia żelatynowo-chitozanowa
folie przeciwdrobnoustrojowe
Opis:
The antimicrobial properties of chitosan solutions and films against selected bacteria and the effect of chitosan incorporation into gelatin films were studied. The bactericidal effect of chitosan solutions increased with time and temperature of sample incubation. Two psychrotrophic strains Pseudomonas fluorescens and Listeria innocua were more sensitive to chitosan than mesophilic strains Escherichia coli and Staphylococcus aureus. The growth of bacteria under chitosan discs was inhibited. In the case of two component gelatin-chitosan films strong antimicrobial effect was also observed.
Zbadano właściwości przeciwdrobnoustrojowe roztworów i folii chitozanowych oraz dwuskładnikowych folii żelatynowo-chitozanowych, wobec wybranych bakterii. Stwierdzono zwiększenie bakteriobójczego działania roztworów chitozanu wraz ze wzrostem temperatury i wydłużeniem czasu inkubacji. Dwa psychrotrofowe szczepy Pseudomonas fluorescens i Listeria innocua wykazały większą wrażliwość na działanie chitozanu niż mezofilne szczepy Escherichia coli i Staphylococcus aureus. Wzrost badanych drobnoustrojów został całkowicie zahamowany pod krążkami z folii chitozanowych. Silne właściwości przeciwdrobnoustrojowe zaobserwowano również w przypadku dwuskładnikowych folii żelatynowo-chitozanowych.
Źródło:
Polimery; 2015, 60, 11-12; 735-741
0032-2725
Pojawia się w:
Polimery
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Cytokines in canine inflammatory bowel disease
Autorzy:
Kolodziejska-Sawerska, A.
Rychlik, A.
Depta, A.
Wdowiak, M.
Nowicki, M.
Kander, M.
Powiązania:
https://bibliotekanauki.pl/articles/32308.pdf
Data publikacji:
2013
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Opis:
Canine inflammatory bowel disease is a group of chronic enteropathies characterized by persistent or recurring gastric symptoms with an unknown etiology which are related to histopathological changes in the mucosa of the small and large bowel in the form of cellular infiltration in the mucosal lamina propria. Recent years have witnessed a growing number of investigations into the role of the immune system and, in particular, cytokines in the development of IBD. In this article, the expression of pro-inflammatory (IL-1, IL-2, IL-5, IL-6, IL-12, IL-18, IFN-γ, TNF-α) and anti-inflammatory cytokines (IL-4, IL-10) was compared in canine patients with IBD based on clinical presentation, breed, lamina propria cell infiltrate and histopathological grade. Only selected studies confirmed higher mRNA expression levels of cytokines IL-2, IL-4, IL-5, IL-12p40, IFN-γ, TNF-α and TGF-β in dogs with IBD in comparison with healthy subjects. GSD were strongly represented in most study populations. Dogs with LPE were characterized by elevated levels of IL-1α, IL-1β, IL-2, IL-5, IL-6, IL-12, TNF-α, TGF-β. The present studies of canine patients with LPC revealed the mRNA expression of cytokines IL-1β, IL-2, IL-4, IL-5, IL-6, IL-10, IL-12p35, IL-12p40, IFN-γ, TNF-α, TGF-β. In the reviewed studies, the progression of IBD was not accompanied by changes in the mRNA expression of IL-1α, IL-1β, IL-2, IL-4, IL-5, IL-6, IL-10, IL-12, IL-18, TNF-α, IFN-γ or TGF-β.
Źródło:
Polish Journal of Veterinary Sciences; 2013, 16, 1
1505-1773
Pojawia się w:
Polish Journal of Veterinary Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Nowe perspektywy leczenia zapalenia spojówek i woreczka łzowego u królików
New prospects for the treatment of conjunctivitis and dacryocystitis in rabbits
Autorzy:
Kolodziejska-Sawerska, A.
Powiązania:
https://bibliotekanauki.pl/articles/861185.pdf
Data publikacji:
2014
Wydawca:
Krajowa Izba Lekarsko-Weterynaryjna
Tematy:
kroliki
choroby zwierzat
zapalenie spojowek
zapalenie woreczka lzowego
przyczyny
objawy chorobowe
diagnostyka
leczenie
Źródło:
Życie Weterynaryjne; 2014, 89, 02
0137-6810
Pojawia się w:
Życie Weterynaryjne
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Atroposelektywna synteza naturalnych chiralnych osiowo związków biarylowych. Część 1
Atroposelective synthesis of natural axially chiral biaryl compounds. Part 1
Autorzy:
Kołodziejska, R.
Tafelska-Kaczmarek, A.
Studzińska, R.
Powiązania:
https://bibliotekanauki.pl/articles/171903.pdf
Data publikacji:
2017
Wydawca:
Polskie Towarzystwo Chemiczne
Tematy:
naturalne chiralne osiowo związki biarylowe
mostkowane biaryle
otwarto-łańcuchowe biaryle
atropoizomeryzacja
atroposelektywna synteza
chiralne osiowo biaryle
natural axially chiral biaryl compounds
bridged biaryls
unbridged biaryls
atropoisomerization
atroposelective synthesis
axially chiral biaryls
Opis:
In early twentieth century, it was already known that chemical compounds might be chiral without containing the chiral atoms. The presence of the stereogenic center is a sufficient but not necessary condition that the molecule appears in two forms which are mirror images. In certain cases, the limit of free rotation in the molecule may result in asymmetry, e.g. inhibition of rotation around single bond leads to axial isomers. This is the kind of conformational isomerism, which according to the nomenclature is called atropisomerism [1, 2]. The most often optically active molecules without stereogenic atoms, possessing an axial chirality are biaryls, which are commonly found in nature. In most cases, pharmacological activity of biaryls is associated with the presence of axial chirality (Figs 1, 2; Scheme 1) [1–14]. Generally chiral biaryls are divided into bridged biaryls (Scheme 4–6) [15–24], and biaryls, which do not contain the additional ring (Scheme 2, 3) [25–33]. The thermal stability of both enantiomeric/diastereomeric forms is an essential precondition for atropisomerism. For a given temperature, conformationally stable isomers may coexist when their a half-life is at least 1000 s, which gives the minimum energy barrier of 93 kJ mol–1 at 300 K. Chiral biaryls can be achieved by either desymmetrization of stable but achiral biaryls by modifying one of the groups on the aromatic moiety (Scheme 7–9) [1, 34, 35], or by dynamic kinetic resolution of racemic mixtures of the conformationally unstable chiral substrates. The synthesis of the chirally stable biaryls from the chiral labile substrates is most frequently the result of the extra substituent addition (Scheme 10) [36], and formation or cleavage of a bridge (Scheme 11–16) [37–54]. The axially chiral biaryls can also be obtained in the atroposelective transformation of the alkyl substituent of the arene ring into a second aromatic ring in the presence of an organometallic catalyst (Scheme 17, 18) [55, 56].
Źródło:
Wiadomości Chemiczne; 2017, 71, 3-4; 177-197
0043-5104
2300-0295
Pojawia się w:
Wiadomości Chemiczne
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Atroposelektywna synteza naturalnych chiralnych osiowo związków biarylowych. Część 2
Atroposelective synthesis of natural axially chiral biaryl compounds. Part 2
Autorzy:
Kołodziejska, R.
Tafelska-Kaczmarek, A.
Studzińska, R.
Powiązania:
https://bibliotekanauki.pl/articles/171989.pdf
Data publikacji:
2017
Wydawca:
Polskie Towarzystwo Chemiczne
Tematy:
chiralne osiowo biaryle
wewnątrzcząsteczkowa reakcja sprzęgania
międzycząsteczkowa reakcja sprzęgania
axially chiral biaryls
intramolecular coupling
intermolecular coupling
Opis:
A direct aryl-aryl coupling reaction is the most common method for the synthesis of axially chiral biaryls. Atroposelective coupling can be accomplished by three main strategies (Scheme 1) [1, 11]: a) intramolecular coupling reaction between two aryl substrates by the use of the chiral tether as a source of asymmetric information (Scheme 2), b) intermolecular reaction of the modified aryl compounds containing a chiral auxiliary. A source of chiral information can be a planar-chiral element, the chiral leaving group, and the chiral ortho substituent (Scheme 12, 16, 17), c) intermolecular coupling in the presence of chiral additives, for example, stoichiometric or catalytic oxidation in the presence of the transition metal complexes containing chiral ligands, and the redox-neutral coupling reactions catalyzed by transition metal complexes with chiral bidentate N/P- -ligands (Scheme 18, 20–22). These methods have been applied in the synthesis of various biologically active compounds. For example, Lipshutzet et al. obtained a fragment of the antibiotic vancomycin [15], and O-permethyltellimagrandin II [16]. Lin and coworkers synthesized (P)-kotanin [17], the natural metabolite from Aspergillus glaucus (Scheme 3). Waldvogel and coworkers [19] received steganacin derivative, a cytostatic drug (Scheme 5). Coleman et al. in the oxidative dimerization reaction of aryls with a chiral ortho substituents obtained a precursor in the synthesis of calphostin A (Scheme 8) [26]. Meyers and coworkers [27, 28] applied the Ullmann homocoupling for the synthesis of gossypol (Scheme 9). The oxidative coupling of phenols allows to obtain the natural precursor of nigerone (Scheme 13) [42]. Whereas the calphostin [18] derivative, an inhibitor of protein kinase C, was obtained by the oxidative coupling reaction (Scheme 4). The schizandrin [23] from Schisandra chinensis and isodiospyrin [24] from Diospyros morrisiana were obtained by intermolecular coupling reaction of aryl substrates with the chiral ortho substituents (Scheme 7).
Źródło:
Wiadomości Chemiczne; 2017, 71, 3-4; 199-217
0043-5104
2300-0295
Pojawia się w:
Wiadomości Chemiczne
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Enancjoselektywna enzymatyczna desymetryzacja katalizowana lipazami. Część 1, Związki prochiralne
Enantioselectve enzymatic desymmetrization catalyzed in the presence of lipase. Part 1, Prochiral compounds
Autorzy:
Kołodziejska, R.
Karczmarska-Wódzka, A.
Tafelska-Kaczmarek, A.
Studzińska, R.
Dramiński, M.
Powiązania:
https://bibliotekanauki.pl/articles/171684.pdf
Data publikacji:
2013
Wydawca:
Polskie Towarzystwo Chemiczne
Tematy:
związki prochiralne
desymetryzacja
transestryfikacja
hydroliza
lipazy
prochiral compounds
desymmetrization
transesterification
hydrolysis
lipase
Opis:
In the enzymatic asymmetric synthesis, the enzyme allows the desymmetrization of achiral compounds resulting in chiral compounds of high optical purity. Therefore, this type of biotransformation is known as enantioselective enzymatic desymmetrization (EED) [1–11]. This method is related to the generation of an asymmetry (loss of symmetry elements) in prochiral molecules (most often an sp3 or sp2 hybridized carbon atom), in meso synthones, and centrosymmetric compounds. An achiral center of the tetrahedral system is defined as a prochiral one if it becomes chiral as a result of one of the two substituents replacement which, when separated from the particles, are indistinguishable (Scheme 1, 2) [1–4, 9, 12]. Asymmetric synthesis is enantioselective when one of the enantiotopic groups or faces of an optically inactive compound is biotransformed faster than the other (Scheme 3–5) [1, 10, 11, 13–15]. Lipases are enzymes of highest importance in stereoselective organic synthesis, mainly due to their exceptionally broad substrate tolerance, stability, activity in unphysiological systems, and relatively low price [9, 14]. The mechanism of enzymatic hydrolysis catalysed by hydrolases is similar to that observed in the chemical hydrolysis with the use of base. The selectivity of enzymatic catalysis depends on the substrate orientation in the enzyme active site (Scheme 6, 7) [25–29]. Lipases were successfully used for the desymmetrization of different prochiral diesters, alcohols and amines. Most lipases preferentially convert the same prochiral groups in the above mentioned types of reaction. This allows the preparation of the both enantiomers of the product in high chemical and optical yield (Scheme 9–13) [9, 13, 32–56].
Źródło:
Wiadomości Chemiczne; 2013, 67, 7-8; 751-772
0043-5104
2300-0295
Pojawia się w:
Wiadomości Chemiczne
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Enancjoselektywna enzymatyczna desymetryzacja katalizowana oksydoreduktazami. Dehydrogenazy w reakcji redukcji. Część I
Enantioselective enzymatic desymmetrization catalyzed by oxidoreductases. Dehydrogenases in reduction reactions. Part I
Autorzy:
Kołodziejska, R.
Karczmarska-Wódzka, A.
Tafelska-Kaczmarek, A.
Studzińska, R.
Wróblewski, M.
Augustyńska, B.
Powiązania:
https://bibliotekanauki.pl/articles/171686.pdf
Data publikacji:
2014
Wydawca:
Polskie Towarzystwo Chemiczne
Tematy:
redukcja asymetryczna
dehydrogenaza alkoholowa
kofaktor
asymmetric reduction
alcohol dehydrogenase
cofactor
Opis:
Enzymes act as biocatalysts whether are also mediating in all anabolic and catabolic pathways, playing an extremely important role in the cells of all life forms. Catalytic potential of oxidoreductases is most commonly used in reduction reactions. Dehydrogenases and reductases catalyze the reversible desymmetrization reactions of meso and prochiral carbonyl compounds and alkenes. The oxidoreductase- catalyzed reactions require cofactors to initiate catalysis. In most cases, it is nicotinamide adenine dinucleotide (NADH) or its phosphorylated derivative (NADPH), which acts as a hydride donor. The necessity of employing expensive cofactors was, for the long time, one of the main limitations to the use of dehydrogenases. This problem was solved by developing a regeneration system of a cofactor in the reaction environment. Various systems are used for the cofactor recycling. In the case of a carbonyl compound reduction, an irreversible oxidation of formic acid to carbon dioxide is most frequently used. In this paper, selected examples of whole-cell and isolated enzymes applications in the carbonyl compound reduction are discussed. The application of baker’s yeast, microorganisms and dehydrogenases in enantioselective enzymatic desymmetrization (EED) of prochiral ketones leads to a broad spectrum of chiral alcohols used as intermediates in the syntheses of many pharmaceuticals and compounds presenting a potential biological activity.
Źródło:
Wiadomości Chemiczne; 2014, 68, 9-10; 763-782
0043-5104
2300-0295
Pojawia się w:
Wiadomości Chemiczne
Dostawca treści:
Biblioteka Nauki
Artykuł

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