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1

Enancjoselektywna redukcja wybranych α-aryloketonów w kulturach szczepów Coryneum betulinum KCh 6534 i Chaetomium sp. KCh 665

Janeczko T., Świzdor A., Chmolowska D., Dmochowska-Gładysz J., Kozłowska E., Dymarska M., Kostrzewa-Susłow E.

Przemysł Chemiczny

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2016

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T. 95, nr 8

1617--1621

PL

Przeprowadzono biotransformacje piętnastu substratów w kulturach dwóch szczepów grzybów strzępkowych: Coryneum betulinum KCh 6534 i Chaetomium sp. KCh 6651. Badane biokatalizatory charakteryzują się bardzo wysoką specyficznością substratową. Zaobserwowano wyraźny wpływ budowy zastosowanego substratu na stopień konwersji oraz enancjoselektywność procesu redukcji. W kulturze C. betulinum uzyskano enencjomerycznie czysty (S)-1-(1-naftylo)-etanol i (S)-1-(6-tetralino)-etanol. W kulturze szczepu z gatunku Chaetomium uzyskano z wysokim nadmiarem enancjomerycznym zarówno alkohole o konfiguracji absolutnej S: 1-(4-bromofenylo)-etanol i 1-cykloheksyloetanol, jak i R: 1-(4-metylofenylo)-etanol i 7-metoksy-1-tetralol.

EN

Fifteen α-aryloketones were biotransformed to resp. enantimerically pure EtOH or tetralol derivatives by using Coryneum betulinum KCh 6534 and Chaetomium sp. KCh 6651 strains of filamentous fungi. A very high substrate specificity and a significant impact of the substrate structure on the conversion and enantioselectivity of the redn. were obsd. In the culture of C. Betulinum, enantiomarically pure (S)-1-(1-naphthyl)-ethanol and (S)-1-(6-tetralino)-ethanol were obtained. On the contrary, both (S)-(1-(4-bromo- phenyl)-ethanol and 1-cyclohexylethanol) as well as (R)-(1-(4-methylphenyl)ethanol and (R)-7-methoxy-1-tetralol were produced in the culture of Chaetomium species in high enantiomeric excess.

2

Katalizowane cynkiem asymetryczne hydrosililowanie ketonów i imin

Gajewy J.

Wiadomości Chemiczne

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2013

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[Z] 67, 5-6

521--562

EN

One of the fundamental research goals in modern chemistry is the development of efficient and selective procedures to access organic compounds. Among all of the methodologies developed so far, catalysis offers an efficient and economical approach to enantiomericaly pure substances. In particular, transition metal catalysts modified by ligands, usually phosphines, are one of most successful examples of practical catalysis. Unfortunately, most of the applied metals (e.g., Pd, Rh, Ru, Ir) are low abundant, toxic and expensive. For this reason, recent research is focusing on their replacement by cheaper and low toxic metals. For example, the use of zinc can be of great interest, due to its abundance (0.0076% in the earth crust), biological relevance and distinct abilities. In the last two decades many scientific group have been working on finding new, high efficient and inexpensive catalytic system based on zinc for enantioselective transformations. It has been found that many of important organic reactions (for example aldol, Diels-Alder, Friedel-Crafts, Henry reactions) in their asymmetric version can be catalyzed by zinc complexes. One of them is also asymmetric reduction of double carbon-heteroatom bonds through addition of hydride (from silane). Hydrosilylation reduction is a promising alternative for the catalytic transformation of organic molecules to other reduction methods such as: hydrogenation and transfer hydrogenation owing to its operational simplicity and mild conditions. This review will give a general overview of the possible applications of zinc-catalyzed hydrosilylation of carbonyl compounds and imines. Since the understanding of mechanism of reaction is crucial for rational planning of new and more efficient ligands, some part of this article was devoted for mechanical considerations.

3

Ionic liquids as the catalysts for asymmetric reactions

Dąbrowski Z., Wiśniewska A., Kulig-Adamiak A., Kamiński J.

Polimery

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2012

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T. 57, nr 5

375-381

EN

A new 7 functionalized chiral ionic liquids (CILs) based on pyrrolidine have been synthesized from (S)-proline as a main substrat. The obtained compounds have 1-[(S)-(pyrrolidin-2-yl)methyl]-3-alkylimidazolium cation and bis(trifluoromethylsulfonyl)imide and hexafluorophosphate anions. The structures of the obtained catalysts were determined by spectroscopic analysis 1H NMR, 13C NMR and 19F NMR. This chiral ionic liquids have been applied as efficient catalysts for Michael addition of cyclohexanone to nitroalkenes.

PL

Na bazie (S)-proliny zsyntezowano 7 nowych funkcjonalizowanych chiralnych cieczy jonowych zawierających kation 1-[(S)-(pirolidyno-2-ylo)metylo]-3-alkiloimidazoliowy oraz aniony: bis(trifluorometylosulfonylo)imidkowy i heksafluorofosforanowy. Struktury uzyskanych związków określono metodami spektroskopowymi 1H NMR, 13C NMR i 19F NMR. Zsyntezowane ciecze jonowe zastosowano jako skuteczne katalizatory addycji Michaela cykloheksanonu do nitroalkenów.

4

Enzymatyczne utlenianie typu Baeyera-Villgera

Kołek T., Świzdor A., Panek A.

Wiadomości Chemiczne

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2009

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[Z] 63, 9-10

819-845

EN

Baeyer-Villiger (BV) reaction is oxidation of ketones, leading to cleavage of one of the C-CO-C bonds with simultaneous insertion of an oxygen atom into the cleaved bond. Resulting products obtained from cyclic ketones are lactones, while esters are obtained from acyclic ketones. Numerous strains of microorganisms produce enzymes catalyzing BV oxidation. These enzymes participate in the processes of degradation of natural and synthetic ketones, which can be used by the microorganisms as carbon source (Scheme 3 and 4). The enzymes are monooxygenases (Baeyer-Villigerases, BVMOs), usually containing flavinoadenine nucleotide and cooperating with NAD(P)H reductases. Research on the role of BV oxidation in degradation processes has evolved into intensive studies on the mechanism of this reaction and its use in synthesis, especially after isolation (in 1976) of cyclohexane monooxygenase from Acinetobacter sp. NCIB9871(CHMOAcineto 1) [9]. Subsequently, further strains were identified which produced BVMOs catalyzing oxidation of ketones of diverse structures. In addition to the best-characterized cyclohexane monooxygenase, there are: cyclopentanone, phenylacetone, cyclododecanone, aliphatic ketone and 2-oxo-3-en-4,5,5-trimethyl-cyclopentenylacetic acid monooxygenases. The adjective characterizing a given BVMO is derived from the ketone constituting carbon source, or from the ketone which is oxidized with the highest yield. In addition to these ketones, the enzymes accept their various structural analogues, therefore it is possible to select a biocatalyst which carries out oxidation of a given substrate. Among BVMOs, particularly selective are the enzymes carrying out BV oxidation of steroidal ketones: these enzymes operate only on steroid substrates, mostly containing 3-oxo--4-en moiety, but also they exhibit regioselectivity as well - the oxidation of ketones takes place only at C-17. During the regioselective enzymatic oxidation, "atypical" lactones [2, 4], which are not produced in chemical BV oxidation processes, are sometimes formed. Products of stereoselective enzymatic reactions are optically pure lactones and esters, which are starting points for further asymmetric synthesis of biologically active compounds, including medicines. The application of genetic engineering allows obtaining recombinant microbial strains, which are non-pathogenic and produce larger amounts of the enzyme than the wild-type strains. The recombinants are also able to produce mutated BVMOs exhibiting higher selectivity and/or lifetime, as well as activity towards different spectrum of substrates than the parent enzymes [2]. However, reaction yields of transformations carried out by the recombinants are still not significantly better than the results obtained with the wild-type strains. The recombinants usually require an expensive reagent, isopropyl-? --D-tiogalactopyranoside (ITPG), to induce their BVMOs [23]. Enzymatic BV oxidation, due to the selectivity of the enzymatic action, is competitive to the chemical oxidation. The enzyme selectivity allows for using pure products, including enantiopure compounds, with high yield. The process is environmentally friendly, because the oxidizer in the enzymatic BV reaction is molecular oxygen, and the amount of byproducts is limited. Synthetic application of BVMOs is limited by three principal factors: isolation of the enzyme in amounts suitable for large-scale applications, decrease in the enzymatic activity in the presence of the substrate and/or the product, and the isolation of the product. Separation of the unreacted enantiomer of the substrate in the process of kinetic separation of the racemic mixture, or separation of regioisomeric lactones are costly and time-consuming operations. Another possible problem is the fact that some strains producing useful BVMOs are pathogenic. Therefore, multidirectional research efforts are devoted to overcome the aforementioned barriers with the goal of establishing economically viable methods of biotransformations [4].

5

Mikrobiologiczna enancjoselektywna redukcja acetylowych pochodnych pirydyny

Janeczko T., Dmochowska-Gładysz J., Kostrzewa-Susłow E.

Przemysł Chemiczny

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2009

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T. 88, nr 5

458-460

6

Enantioselective Diethylzinc Addition to Aldehydes Catalyzed by Novel L-Arabinose Derived Amino Alcohols

Bauer T., Bielecka M.

Polish Journal of Chemistry

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2008

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Vol. 82, nr 7

1425-1425

EN

Two novel amino alcohols were synthesized from L-arabinose and applied for the enantioselective diethylzinc addition. The enantioselectivity for new ligands was much lower than for previously re ported rigid D-glucosamine derived ligand.

7

D-Glucosamine Derivatives as Ligands in Highly Enantioselective Palladium-catalyzed Allylic Alkylations

Bauer T., Bartoszewicz A.

Polish Journal of Chemistry

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2007

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Vol. 81, nr 12

2115-2120

EN

The rigid derivative of D-glucosamine bearing single diphenylphosphino benzoic acid moiety was synthesized and applied as the ligand for the allylic alkylations. Best results were obtained for 1,3-diphenylpropenyl acetate (up to 96% ee).

8

Lipase-Catalysed Resolution of 1-Hydroxyethane-P-phenylphosphinates

Majewska P., Kafarski P., Lejczak B.

Polish Journal of Chemistry

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2005

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Vol. 79 / nr 3

561-566

EN

Lipase-catalysed hydrolysis and transesterification were used to obtain _-hydroxyalkanephosphinates with two stereogenic centers, namely at_-carbon and phosphorus atoms. These compounds were chosen to check if there is a transfer of chirality from carbon to phosphorus atom during lipase catalysed reactions.

9

Terpenic Alcohols - Source of Chirality in Condensing Reagents in Peptide Chemistry

Kamiński Z., Kolesińska B., Markowicz S., Pokrzeptowicz K.

Polish Journal of Chemistry

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1999

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Vol. 73, nr 12

1965-1968

EN

Chiral 2,4-dichloro-6-terpenyloxy-1,3,5-triazines 3a-d obtained by treatment of cyanuric chloride with isomyrtanol (1), nopol (2), isopinocampheol (3) and borneol (4) are useful as enantiodifferentiating coupling reagent in the synthesis of dipeptides

10

ph Dependent Enantioselection of Amino Acids by Phosphorous-Containing Calix[4]resorcinarene in Langmuir Monolayers

Pietraszkiewicz M., Prus P., Bilewicz R.

Polish Journal of Chemistry

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1999

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Vol. 73, nr 12

2035-2042

EN

Lipophilic calix[4]resorcinarene with phosphorous acid amide groups linking oxygen atoms is a rigid system of the cavitand type, in which conformational flexibility is strongly limited. These chiral receptors form stable Langmuir monolayers on water surface with surface area per molecule in the compressed layer being almost ph-independent.

11

pH Dependent Enantiomeric Recognition of Amino Acids by Mannich-Type Calix[4]resorcinarenes in Langmuir Monolayers

Pietraszkiewicz M., Prus P., Bilewicz R.

Polish Journal of Chemistry

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1999

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Vol. 73, nr 11

1845-1853

EN

The surface potential of these compounds is distinctly higher in the presence of substituents and its further increase upon decreasing the pH of the subphase is observed only for the derivatized calixarenes. This means that protonation on the amine centers is the factor determining the properties of the monolayer.