Chemoenzymatic resolution of β-azidophenylethanols by candida antarctica and their application for the synthesis of chiral benzotriazoles

The kinetic resolutions of (±)-β-azidophenylethanols were carried out using lipase from Candida antarctica, and enantiomerically enriched (R)-β-azidophenylethanols and their corresponding (S)-β-azidophenylethyl acetates were obtained in good enantiomeric excesses (up to > 99%). The enantiomerically enriched (R)-β-azidophenylethanols were subjected to cyclization reaction with 2-(trimethylsilyl)phenyl triflate and CsF producing chiral 1,2,3-benzotriazole compounds in good yields (75-86%) by a [3 + 2] cycloaddition, which involves the benzyne formation.As resoluções cinéticas de (±)-β-azidofeniletanóis foram realizadas usando a lipase de Candida antarctica fornecendo os compostos enantiomericamente enriquecidos, (R)-β-azidofeniletanóis e acetato de (S)-β-azidofeniletila em bons excessos enantioméricos (até > 99%). Os (R)-β-azidofeniletanóis enantiomericamente enriquecidos foram submetidos à reação de ciclização com o triflato de 2-(trimetilsilil)fenila e CsF resultando em 1,2,3-benzotriazóis em bons rendimentos (75-86%) pela reação de cicloadição [3 + 2], a qual envolve a formação in situ de benzino.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Universidade de São Paulo Instituto de Química de São CarlosUniversidade Federal de São Paulo (UNIFESP) Departamento de Ciências Exatas e da TerraUniversidade Estadual de Mato Grosso do Sul Coordenação de QuímicaUNIFESP, Depto. de Ciências Exatas e da TerraSciEL

Reduction of acetophenones derivatives and resolution phenylethanol by biocatalysis and immobilization of marine fungi

Este trabalho envolveu reações de biocatálise com objetivo de obter compostos enantiomericamente puros. Assim foram realizadas reações de redução de derivados de acetofenonas, resolução enzimática de alcoóis e azido-alcoóis e imobilização de células fúngicas em suportes sólidos para aplicação em biocatálise. Foi realizada a redução enantiosseletiva da 1-(4-metoxifenil)etanona (1) através da triagem com nove fungos marinhos (Aspergillus sydowii CBMAI 935, A. sydowii CBMAI 934, A. sclerotiorum CBMAI 849, Bionectria sp. CBMAI 936, Beauveria felina CBMAI 738, Cladosporium cladosporioides CBMAI 857, Mucor racemosus CBMAI 847, Penicillium citrinum CBMAI 1186, P. miczynskii CBMAI 930). Os fungos A. sydowii CBMAI 935 e Bionectria sp. CBMAI 936 catalisaram a biorredução estereosseletiva da 1-(4-metoxifenil)etanona (1) para o correspondente (R)-1-(4-metoxifenil)etanol (1a) com excelentes excessos enantioméricos (>99%). Os fungos B. felina CBMAI 738 e P. citrinum CBMAI 1186 catalisaram a biorredução estereosseletiva da cetona 1 para o correspondente S-álcool 1a com 69% de excesso enantiomérico. Os fungos marinhos (A. sclerotiorum CBMAI 849, A. sydowii CBMAI 934, B. felina CBMAI 738, M. racemosus CBMAI 847, P. citrinum CBMAI 1186, P. miczynskii CBMAI 931, P. miczynskii CBMAI 830, P. oxalicum CBMAI 1185, Trichoderma sp. CBMAI 932) foram utilizados na bioconversão assimétrica das iodoacetofenonas 2-4 para os correspondentes iodofeniletanois 2a-4a. Todos os fungos marinhos produziram exclusivamente (S)-o-iodofeniletanol (2a) e (S)-m-iodofeniletanol (3a) com diferentes valores de excessos enantioméricos (62-99%). Os fungos B. felina CBMAI 738, P. miczynskii CBMAI 830, P. oxalicum CBMAI 1185 e Trichoderma sp. CBMAI 932 produziram o correspondente (R)-p-iodofeniletanol (4a) com excessos enantioméricos de 32-99%. A bioconversão da p-iodoacetofenona (4) com células microbianas do P. oxalicum CBMAI 1185 mostrou uma competição entre a reação de redução e oxidação. Também foram realizadas as reduções das ceto-azidas 13-16 com fungos marinhos fornecendo bons resultados de seletividade (28-99% ee). As células microbianas dos fungos A. sclerotiorum CBMAI 849 e P. citrinum CBMAI 1186 foram imobilizadas em suportes de sílica gel, xerogel de sílica e quitosana. As células do P. citrinum CBMAI 1186 imobilizadas em quitosana catalisaram a redução da 1-(4-metoxifenil)-etanona (1) para o correspondente (S)-1-(4-metoxifenil)-etanol (1a) com excelente excesso enantiomérico (>99%). O fungo P. citrinum CBMAI 1186 imobilizado em quitosana também catalisou a biorredução de 2-cloro-1-feniletanona (7) para o 2-cloro-1-feniletanol (7a), mas neste caso, sem seletividade. Neste trabalho também foram realizadas as resoluções quimio-enzimáticas dos (±)-o-iodofeniletanol (2a), (±)-m-iodofeniletanol (3a), (±)-p-iodofeniletanol (4a), (±)-2-azido-1-feniletanol (13a), (±)-2-azido-1-(4-metoxifenil)etanol (14a), (±)-2-azido-1-(4-bromofenil)etanol (15a), (±)-2-azido-1-(4-nitrofenil)etanol (16a) e (±)-2-azido-1-(4-clorofenil)etanol (17a) com a lipase CALB. Os (S)-m-iodofeniletanol (3a) e (S)-p-iodofeniletanol (4a) foram obtidos com excelentes excessos enantioméricos (>99%) e posteriormente foram utilizados na síntese de compostos bifenílcos quirais por reação de acoplamento Suzuki fornecendo bons rendimentos (63-65%). A resolução quimio-enzimática dos azido-alcoóis 13a-17a foram realizadas com lipase Candida atarctica e os (R)-2-azido-1-feniletanol (13a), (R)-2-azido-1-(4-metoxifenil)etanol (14a), (R)-2-azido-1-(4-bromofenil)etanol (15a), (R)-2-azido-1-(4-nitrofenil)etanol (16a) obtidos foram utilizados na síntese dos triazóis quirais (R)-2-(1H-benzo[d][1,2,3]triazol-1-il)-1-feniletanol (13), (R)-2-(1H-benzo[d][1,2,3]triazol-1-il)-1-(4-metoxifenil)etanol (14), (R)-2-(1H-benzo[d][1,2,3]triazol-1-il)-1-(4-bromofenil)etanol (15) e (R)-2-(1H-benzo[d][1,2,3]triazol-1-il)-1-(4-nitrofenil)etanol (16) e (R)-2-(1H-benzo[d][1,2,3]triazol-1-il)-1-(4-clorofenil)etanol (17), obtidos com ótimos rendimentos (79-85%).This work involved reactions of biocatalysis in order to obtain enantiomerically pure compounds. Thus reactions were performed reduction of acetophenones derivatives, enzymatic resolution of azido-alcohols, secondary alcohols and immobilization of fungal cells on solid supports for use in biocatalysis. We performed the enantioselective reduction of 1-(4-methoxyphenyl)ethanone (1) by screening with nine marine fungi (Aspergillus sydowii CBMAI 935, A. sydowii CBMAI 934, A. sclerotiorum CBMAI 849, Bionectria sp. CBMAI 936, Beauveria felina CBMAI 738, Cladosporium cladosporioides CBMAI 857, Mucor racemosus CBMAI 847, Penicillium citrinum CBMAI 1186, P. miczynskii CBMAI 930). The fungi A. sydowii CBMAI 935 and Bionectria sp. 936 CBMAI catalyzed stereoselective bioreduction of 1-(4-methoxyphenyl)ethanone (1) to the corresponding (R)-1-(4-methoxyphenyl)ethanol (1a) with excellent enantiomeric excess (>99%). Fungi B. felina CBMAI 738 and P. citrinum 1186 CBMAI catalyzed stereoselective bioreduction of ketone 1 to the corresponding S-alcohol 1a with 69% enantiomeric excess. The marine fungi (A. sclerotiorum CBMAI 849, A. sydowii CBMAI 934, B. felina CBMAI 738, M. racemosus CBMAI 847, P. citrinum CBMAI 1186, P. miczynskii CBMAI 931, P. miczynskii CBMAI 830, P. oxalicum CBMAI 1185, Trichoderma sp. CBMAI 932) were used in the bioconversion of asymmetric iodoacetophenones 2-4 to the corresponding iodophenylethanols 2a-4a. All marine fungi produced exclusively (S)-o-iodophenylethanol (2a) and (S)-m-iodophenyletanol (3a) with different values of enantiomeric excess (62-99%). Fungi B. felina CBMAI 738, P. miczynskii CBMAI 830, P. oxalicum CBMAI 1185 and Trichoderma sp. CBMAI 932 produced the corresponding (R)-p-iodophenylethanol (4a) with enantiomeric excess of 32-99%. The bioconversion of p-iodoacetophenone (4) with microbial cells of P. oxalicum CBMAI 1185 showed a competition between oxidation and reduction reaction. Were also performed reductions of azido-ketones 13-16 with marine fungi providing good results of selectivity (28-99% ee). Microbial cells of fungi A. sclerotiorum CBMAI 849 and P. citrinum CBMAI 1186 were immobilized on supports of silica gel, silica xerogel and chitosan. Whole cells of P. citrinum 1186 CBMAI immobilized on chitosan catalyzed the reduction of 1-(4-methoxyphenyl)ethanone (1) to the corresponding (S)-1-(4-methoxyphenyl)ethanol (1a) with excellent enantiomeric excess (>99%). The fungus P. citrinum 1186 CBMAI immobilized on chitosan also catalyzed the bioreduction of 2-chloro-1-phenylethanone (7) to 2-chloro-1-phenylethanol (7a), but in this case without selectivity. In this work were also performed chemo-enzymatic resolutions of (±)-o-iodophenylethanol (2a), (±)-m-iodophenylethanol (3a), (±)-p-iodophenylethanol (4a), (±)-2-azido-1-phenylethanol (13a), (±)-2-azido-1-(4-methoxyphenyl)ethanol (14a), (±)-2-azido-1-(4-bromophenyl)ethanol (15a), (±)-2-azido-1-(4-nitrophenyl)ethanol (16a) and (±)-2-azido-1-(4-chlorophenyl)ethanol (17a) with the lipase Candida atarctica. The (S)-m-iodophenylethanol (3a) and (S)-p-iodophenylethanol (4a) were obtained with excellent enantiomeric excess (>99%) and were subsequently used in the synthesis of chiral biphenyl compounds by the Suzuki reaction with good yields (63-65%). Chemoenzymatic resolution of azido-alcohols 13a-17a were carried out using lipase CALB and (R)-2-azido-1-phenylethanol (13a), (R)-2-azido-1-(4-methoxyphenyl)ethanol (14a), (R)-2-azido-1-(4-bromophenyl)ethanol (15a), (R)-2-azido-1-(4-nitrophenyl)ethanol (16a) obtained were used in the synthesis of chiral triazoles (R)-2-(1H-benzo[d][1,2,3]triazol-1-yl)-1-phenylethanol (13), (R)-2-(1H-benzo[d][1,2,3]triazol-1-yl)-1-(4-methoxyphenyl)ethanol (14) (R)-2-(1H-benzo [d][1,2,3]triazol-1-yl)-1-(4-bromophenyl)ethanol (15) and (R)-2-(1H-benzo[d][1,2,3]triazol-1-yl)-1-(4-nitrophenyl)ethanol (16) and (R)-2-(1H-benzo[d] [1,2,3]triazol-1-yl)-1-(4-chlorophenyl)ethanol (17) obtained in good yields (79-85%)

Reduction of derived from acetophenone with fungi of marine origin

Neste trabalho realizou-se o primeiro estudo biocatalítico envolvendo reações de redução de cetonas com fungos de origem marinha. Foram utilizadas 7 cetonas comerciais como substratos e 8 fungos derivados marinhos como biocatalisadores. Os fungos foram isolados das esponjas marinhas Geodia corticostylifera (Trichoderma sp Gc1, Penicillium miczynskii Gc5, Aspergillus sydowii Gc12) e Chelonaplysylla erecta (Bionectria sp Ce5, Aspergillus sydowii Ce15, Penicillium raistrickii Ce16 e Aspergillus sydowii Ce19). A redução α-cloroacetofenona (1) foi estudada sob várias condições de reação (mudanças de pH, adição ou ausência de glicose) e o melhor resultado foi com fungo P. miczynskii Gc5, pois se obteve um rendimento isolado de 60 % e excesso enantiomérico de 50 % para a (S)-2-cloro-1-feniletanol (1a). O interessante nestes estudos foi que todos os fungos utilizados na triagem com a α-cloroacetofenona (1) apresentaram seletividade anti-Prelog. Na literatura é comum obter redução enzimática com seletividade Prelog. A α-bromoacetofenona (2) foi biotransformada pelo fungo A. sydowii Ce19 nos correspondentes compostos: (S)-2-bromo-1-feniletanol (2a), (S)-2-cloro-1-feniletanol (1a), enquanto que a α-hidroxiacetofenona (2c), α-clorocetofenona (1) e o epóxido-estireno (2b) foram obtidos por reações não enzimáticas. A p-bromo-α-bromoacetofenona (3) e a p-nitro-α-bromoacetofenona (4) foram totalmente biodegradadas pelo fungo A. sydowii Ce19. A redução biocatalítica da orto-iodoacetofenona (5) e meta-iodoacetofenona (6) com o fungo Trichoderma sp Gc1 forneceu o orto-iodo-1-feniletanol (5a) e o meta-iodo-1-feniletanol (6a) com excelentes excessos enantioméricos (e.e. > 99 %). Ficou comprovado também neste trabalho que os fungos derivados marinhos para promover as reações de redução por biocatálise precisam ser cultivados em água do mar artificial. Enquanto a p-iodoacetofenona (7) produziu o p-iodo-1-feniletanol (7a) com e.e. 48 %.This work carried out the first biocatalytic study involving reactions of reduction of ketones with marine-derived fungi. In this study were utilized 7 commercial ketones as substrates and 8 marine-derived fungi as biocatalysts. The fungi were isolated from the marine sponges Geodia corticostylifera (Trichoderma sp Gc1, Penicillium miczynskii Gc5, Aspergillus sydowii Gc12) and Chelonaplysylla erecta (Bionectria sp Ce5, Aspergillus sydowii Ce15, Penicillium raistrickii Ce16 and Aspergillus sydowii Ce19). The reduction of 2-chloro-1-phenylethanone was studied under several conditions of reaction (changes of pH, addition or absence of glucose) and the best result was with fungus P. miczynskii Gc5, therefore it was isolated in modest yield of 60% and enantiomeric excess of 50% for the (S)-(+)-2-chloro-1-phenylethanol. The interesting in these studies was that all the fungi utilized in the screening with the 2-chloro-1- phenylethanone presented selectivity anti-Prelog. In the literature is common to obtain enzymatic reduction with Prelog selectivity. The 2-bromo-1-phenylethanone was biotransformated by the fungus A. sydowii Ce19 in the (S)-2-bromo-1-phenylethanol, (S)-2-cloro-1-phenylethanol, whereas the α-hydroxy-acetophenone, 2-chloro-1- phenylethanone and the 2-phenyloxirane were obtained by no enzymatic reactions. The 2-bromo-1-(4-bromophenyl)ethanone and the 2-bromo-1-(4-nitrophenyl)ethanone were biodegraded by the fungus A. sydowii Ce19. The biocatalytic reduction of 1-(2- iodophenyl)ethanol and 1-(3-iodophenyl)ethanol with the fungus Trichoderma sp Gc1 afforded the 1-(2-iodophenyl)ethanol and the 1-(3-iodophenyl)ethanol in excellent enantiomeric excesses (e.e. >99 %). It was verified that the marine-derived fungi must grow in artificial sea water to catalyze the reduction reactions

Immobilization of marine fungi on silica gel, silica xerogel and chitosan for biocatalytic reduction of ketones

The scanning electron microscopy (SEM) analysis showed that whole living hyphal of marine fungi Aspergillus sclerotiorum CBMAI 849 and Penicillium citrinum CBMAI 1186 were immobilized on support matrices of silica gel, silica xerogel and/or chitosan. P. citrinum immobilized on chitosan catalyzed the quantitative reduction of 1-(4-methoxyphenyl)-ethanone (1) to the enantiomer (S)-1-(4-methoxyphenyl)-ethanol (3b), with excellent enantioselectivity (ee > 99%, yield = 95%). Interestingly, ketone 1 was reduced with moderate selectivity and conversion to alcohol 3b (ee = 69%, c 40%) by the free mycelium of P. citrinum. This free mycelium of P. citrinum catalyzed the production of the (R)-alcohol 3a, the antipode of the alcohol produced by the immobilized cells. P. citrinum immobilized on chitosan also catalyzed the bioreduction of 2-chloro-1-phenylethanone (2) to 2-chloro-1-phenylethanol (4a,b), but in this case without optical selectivity. These results showed that biocatalytic reduction of ketones by immobilization hyphal of marine fungi depends on the xenobiotic substrate and the support matrix used84160165CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO - CNPQCOORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL DE NÍVEL SUPERIOR - CAPESFUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESPnão temnão temnão te

Immobilization of marine fungi on silica gel, silica xerogel and chitosan for biocatalytic reduction of ketones

The scanning electron microscopy (SEM) analysis showed that whole living hyphal of marine fungi Aspergillus sclerotiorum CBMAI 849 and Penicillium citrinum CBMAI 1186 were immobilized on support matrices of silica gel, silica xerogel and/or chitosan. P. citrinum immobilized on chitosan catalyzed the quantitative reduction of 1-(4-methoxyphenyl)-ethanone (1) to the enantiomer (S)-1-(4-methoxyphenyl)-ethanol (3b), with excellent enantioselectivity (ee > 99%, yield = 95%). Interestingly, ketone 1 was reduced with moderate selectivity and conversion to alcohol 3b (ee = 69%, c 40%) by the free mycelium of P. citrinum. This free mycelium of P. citrinum catalyzed the production of the (R)-alcohol 3a, the antipode of the alcohol produced by the immobilized cells. P. citrinum immobilized on chitosan also catalyzed the bioreduction of 2-chloro-1-phenylethanone (2) to 2-chloro-1-phenylethanol (4a,b), but in this case without optical selectivity. These results showed that biocatalytic reduction of ketones by immobilization hyphal of marine fungi depends on the xenobiotic substrate and the support matrix used. (c) 2012 Elsevier B.V. All rights reserved.10th International Symposium on Biocatalysis and Biotransformations (BIOTRANS)8416016

Biotransformation of α-bromoacetophenones by the marine fungus aspergillus sydowii

The biotransformation reactions of α-bromoacetophenone (1), p-bromo-α-bromoacetophenone (2), and p-nitro-α-bromoacetophenone (3) by whole cells of the marine fungus Aspergillus sydowii Ce19 have been investigated. Fungal cells that had been grown in artificial sea water medium containing a high concentration of chloride ions (1.20 M) catalysed the biotransformation of 1 to 2-bromo-1-phenylethanol 4 (56%), together with the α-chlorohydrin 7 (9%), 1-phenylethan-1,2-diol 9 (26%), acetophenone 10 (4%) and phenylethanol 11 (5%) identified by GC-MS analysis. In addition, it was observed that the enzymatic reaction was accompanied by the spontaneous debromination of 1 to yield α-chloroacetophenone 5 (9%) and α-hydroxyacetophenone 6 (18%) identified by GC-FID analysis. When 2 and 3 were employed as substrates, various biotransformation products were detected but the formation of halohydrins was not observed. It is concluded that marine fungus A. sydowii Ce19 presents potential for the biotransformations of bromoacetophenone derivatives12552557CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO - CNPQCOORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL DE NÍVEL SUPERIOR - CAPESFUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESP307830/2006-3Sem informação2006/54401-