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A concise synthesis of molnupiravir in a one-pot two-step approach starting from uridine is described. Formally, herein, two sets of one-pot two-reaction steps introducing simplicity for purifications and using chemically available reagents are presented. In this context, molnupiravir was obtained in up to 68% overall yield and multigram-scale. In addition, HPLC analysis showed the molnupiravir purity above 99%.

Lamivudine (3TC) is a drug in the antiretroviral class used to treat AIDS / HIV. Featuring two chiral centers, 3TC has two pairs of diastereomers, of which cis - (−) is the first option, as it has biological activity and is not cytotoxic. Due to the great demand for this compound, several synthetic routes were developed for its production. Among them, the enantioselective synthesis of lamivudine from L-menthyl-glyoxylate, which uses L-menthol as a chiral auxiliary, stands out. L-menthyl-glyoxylate is obtained by reacting menthol with some carboxyl derivatives, such as glyoxyl acid, maleic anhydride and fumaric acid. The present work aims to produce this basic component (L-menthyl glyoxylate) using alternative batch and continuous flow methodologies. The synthesis was carried out in two ways: a) from the esterification of menthol with maleic anhydride followed by ozonolysis of dimenthyl maleate and hydration; and b) starting from the esterification of menthol with fumaric acid to synthesize dimenthyl fumarate, followed by ozone and hydration. For all stages, conversions and selectivity above 90% were observed. The ozonolysis of dimenthyl maleate was transposed to continuous flow conditions resulting in conversion and selectivity above 99%. Thus, the work allowed the development of an alternative process to synthesize L-menthyl-glyoxylate, from the use of domestic ozone generator for the reaction of ozonolysis.

The current state of evidence and recommendations for cannabidiol (CBD) and its health effects change the legal landscape and aim to destigmatize its phytotherapeutic research. Recently, some countries have included CBD as an antiepileptic product for compassionate use in children with refractory epilepsy. The growing demand for CBD has led to the need for high-purity cannabinoids on the emerging market. The discovery and development of approaches toward CBD synthesis have arisen from the successful extraction of Cannabis plants for cannabinoid fermentation in brewer's yeast. To understand different contributions to the design and enhancement of the synthesis of CBD and its key intermediates, a detailed analysis of the history behind cannabinoid compounds and their optimization is provided herein.

International audience; This work investigates batch and continuous-flow heterogeneous catalytic hydrogenation of a mixture of cafestol and kahweol (C&K) to obtain pure cafestol. These diterpenes were extracted from green coffee beans, and hydrogenation was performed using well-established palladium catalysts (Pd/C, Pd/CaCO3, Pd/BaSO4, and Pd/Al2O3) and a carbon black-supported Pd catalyst coated by a covalently tethered SiO2 shell with mesoporous texture (Pd/CB@SiO2), all partially deactivated with quinoline. Pd/C 10% poisoned with 1 wt % quinoline gave the best result for batch reaction, producing cafestol from kahweol with high selectivity (>99%) after 10 min. Excellent selectivity was also obtained with the catalyst Pd/CB@SiO2 with only 1% Pd. In addition, Pd/C-quinoline adapted for continuous-flow experiments exhibited the best catalytic activity, also providing cafestol with excellent selectivity (>99%) after 9.8 s.

Benzocaine (ethyl p-aminobenzoate), ethyl ester of p-aminobenzoic acid, is an anesthetic acting as a blocker of the nerve impulses and reducing the permeability of neuronal membrane to sodium iodide, it has become widespread in the pharmaceutical industry having applications as an anesthetic prior to exams such as endoscopy or as a “retarding” agent when inserted in condom. Due to the wide insertion in the pharmaceutical market, the methodologies for obtaining this molecule have already been elucidated and published in the literature, however the application of traditional reactions in refined systems, such as continuous flow are a technological bottleneck that allow approaches aimed at the optimization of productivity. Thus, the present work aimed to apply the reduction and esterification of p-nitrobenzoic acid in one step continuous flow systems, optimizing the reaction time and sequences, in order to add relevance and technology to the process as a whole. The model applied in a continuous flow system generated extremely positive values ​​compared to the present literature, which include results with high conversion (> 99%) and selectivity (> 99%), in residence times that reach up to a minimum of 12 s.

We have investigated the synthesis of p-mentha-2,8-dien-1-ol (1) as a cannabidiol precursor by photochemical oxidation of (R)-limonene (2) with singlet oxygen (1O2) using meso-tetraphenylporphyrin ...

International audience; Studies involving the transformation of lignocellulosic biomass into high value-added chemical products have been intensively conducted in recent years. Its matrix is mainly composed of cellulose, hemicellulose and lignin, being, therefore, an abundant and renewable source for obtaining several platform molecules, with levoglucosan (LG) standing out. This anhydrous carbohydrate can be acylated to obtain carbohydrate fatty acid esters (CFAEs). Here, these compounds were obtained via enzymatic acylation of LG, commercially obtained (Start BioScience®), with different acyl donors in continuous flow. Through the experimental design using a model reaction, it was possible to optimize the reaction conditions, temperature and residence time, obtaining a maximum conversion at 61 C and 77 min. In addition, there was a productivity gain of up to 100 times in all comparisons made with the batch system. Finally, CFAEs were applied in tests of interfacial tension and biological activity. For a mixture of 4-and 2-O-lauryl-1,6-anhydroglucopyranose (MONLAU), the minimum interfacial tension (IFT min) obtained was 96 mN m À1 and the critical micelle concentration (CMC) was 50 mM. Similar values were obtained for a mixture of 4-and 2-O-palmitoyl-1,6-anhydroglucopyranose (MONPAL), not yet reported in the literature, of 88 mN m À1 in 50 mM. For a mixture of 4-and 2-O-estearyl-1,6anhydroglucopyranose (MONEST) and 4-and 2-O-oleoyl-1,6-anhydroglucopyranose (MONOLE), CMC was higher than 60 mM and IFT min of 141 mN m À1 and 102 mN m À1 , respectively. Promising data were obtained for minimal inhibitory concentration (MIC) and minimal bactericidal concentration (MBC) of MONLAU against Staphylococcus aureus strains at 0.25 mM.

Made available in DSpace on 2022-04-28T19:49:23Z (GMT). No. of bitstreams: 0 Previous issue date: 2022-01-01 Universidade Federal do Rio de Janeiro Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Amine transaminases (ATAs) are pyridoxal-5′-phosphate (PLP)-dependent enzymes that catalyze the transfer of an amino group from an amino donor to an aldehyde and/or ketone. In the past decade, the enzymatic reductive amination of prochiral ketones catalyzed by ATAs has attracted the attention of researchers, and more traditional chemical routes were replaced by enzymatic ones in industrial manufacturing. In the present work, the influence of the presence of an α,β-unsaturated system in a methylketone model substrate was investigated, using a set of five wild-type ATAs, the (R)-selective from Aspergillus terreus (Atr-TA) and Mycobacterium vanbaalenii (Mva-TA), the (S)-selective from Chromobacterium violaceum (Cvi-TA), Ruegeria pomeroyi (Rpo-TA), V. fluvialis (Vfl-TA) and an engineered variant of V. fluvialis (ATA-256 from Codexis). The high conversion rate (80 to 99%) and optical purity (78 to 99% ee) of both (R)-and (S)-ATAs for the substrate 1-phenyl-3-butanone, using isopropylamine (IPA) as an amino donor, were observed. However, the double bond in the α,β-position of 4-phenylbut-3-en-2-one dramatically reduced wild-type ATA reactivity, leading to conversions of 99% ee. Computational docking simulations showed the differences in orientation and intermolecular interactions in the active sites, providing insights to rationalize the observed experimental results. Institute of Chemistry UNESP-São Paulo State University, SP Institute of Chemistry Federal University of Rio de Janeiro, RJ Department of Biotechnology & Enzyme Catalysis Institute of Biochemistry Greifswald University Institute of Chemistry UNESP-São Paulo State University, SP FAPESP: 2014/50249-8 FAPESP: 2014/50926-0 FAPESP: 2019/15230-8 CNPq: 465637/2014-0 CNPq: 490278/2013-2

International audience; During recent decades, the use of enzymes or chemoenzymatic cascades for organic chemistry has gained much importance in fundamental and industrial research. Moreover, several enzymatic and chemoenzymatic reactions have also served in green and sustainable manufacturing processes especially in fine chemicals, pharmaceutical, and flavor/fragrance industries. Unfortu- nately, only a few processes have been applied at industrial scale because of the low stabilities of enzymes along with the problematic processes of their recovery and reuse. Immobilization and co-immobilization offer an ideal solution to these problems. This review gives an overview of all the pathways for enzyme immobilization and their use in integrated enzymatic and chemoenzymatic processes in cascade or in a one-pot concomitant execution. We place emphasis on the factors that must be considered to understand the process of immobilization. A better understanding of this fundamental process is an essential tool not only in the choice of the best route of immobilization but also in the understanding of their catalytic activity.

Sustainability in chemistry heavily relies on heterogeneous catalysis. Enzymes, the main catalyst for biochemical reactions in nature, are an elegant choice to catalyze reactions due to their high activity and selectivity, although they usually suffer from lack of robustness. To overcome this drawback, enzyme-decorated nanoporous heterogeneous catalysts were developed. Three different approaches for Candida antarctica lipase B (CAL-B) immobilization on a covalent organic framework (PPF-2) were employed: physical adsorption on the surface, covalent attachment of the enzyme in functional groups on the surface and covalent attachment into a linker added post-synthesis. The influence of the immobilization strategy on the enzyme uptake, specific activity, thermal stability, and the possibility of its use through multiple cycles was explored. High specific activities were observed for PPF-2-supported CAL-B in the esterification of oleic acid with ethanol, ranging from 58 to 283 U mg-1 , which was 2.6 to 12.7 times greater than the observed for the commercial Novozyme 435.

Capecitabine is an important anticancer drug whose synthesis comprises late-stage carbamoylation and ester hydrolysis. Herein we report the use of the Schotten–Baumann reaction in order to perform ...

Here, we report a flow chemistry approach for kinetic resolution of (±)-1,2-propanediol protected by trityl group using the packed-bed reactor filled with different immobilized enzymes. It was investigated the performance of 16 immobilized lipases, including commercial Lipozyme TL, Novozym 51032, Novozym 435 (N435) and lipases immobilized by our group. Based on the values of conversion and enantioseletivity, batch experiments were then translated to the continuous-flow environment. Continuous flow (CF) reactors allowed reaction time reduction, from 6 h in batch to 7 min, keeping the values of conversion (up to 50%) and selectivity (E value >200) during the reaction procedure using the commercial enzyme Novozym 435. In addition, continuous flow conditions increased the productivity of kinetic resolution 3 times when compared to conventional batch reactor, after its optimization.

Among several value-added products from glycerol, glyceryl carbonate (GC) has gained prominence during the recent years because of its attractive physicochemical properties and the wide range of industrial applications. As a continuation of our efforts on GC production under environmentally benign conditions, in this work, we have applied a combination of two new biocatalysts containing lipases from porcine pancreas and Candida antarctica immobilized on epoxy resins for GC production via an integrated reaction between triacylglycerol and dimethyl carbonate under both batch and packed-bed reactors. Under continuous flow conditions, the 1:1 (w/w) combination of the home-made immobilized biocatalysts was able to lead to complete conversion of GC with >99% selectivity against 88% demonstrated by the commercial preparation Novozym 435. The new continuous flow biocatalytic system demonstrated a final productivity of 16 × 10–2 g of GC/h/U of the biocatalyst.

Continuous-flow production of chiral intermediates plays an important role in the development of building blocks for Active Pharmaceutical Ingredients (APIs), being α-amino acids and their derivatives widely applied as building blocks. In this work we developed two different strategies for the synthesis of intermediates used on the synthesis of levetiracetam/brivaracetam and ethambutol. The results obtained show that methionine methyl ester can be continuously converted to the desired ethambutol intermediate by RANEY® Nickel dessulfurization/reduction strategy whereas levetiracetam/brivaracetam intermediates could be synthesized by both RANEY® Nickel (without H2) and Pd/C-H2 approach or by photochemical desulfurization.

Lignocellulose-based bamboo powder was used as pristine support to immobilize two different biocatalysts: Candida Antarctica lipase B and Rhizomucor miehei lipase. Both, IB-CalB and IB-RM, physically absorbed on bamboo carrier presented considerable recycling efficiency, up to 10 consecutive cycles, in batch mode for the ethyl palmitate synthesis with conversion about 50 and 80 %, respectively. The kinetic resolution of racemic-1-phenylethanol mediated by IB-CalB showed a higher conversion against the IB-RM in batch mode. IB-CalB packed into a glass column reactor was used to carry on a kinetic resolution in flow mode regime with an intensification conversion up to 45 % with 99 % e.e. The easy and low-cost method of the lipase adsorption without pre-treatment of the carrier can be promising for industrial biocatalytic transformation and immobilization strategy.

International audience; Lignocellulosic biomass is the most abundant carbon source and it is a base of the whole biorefinery concept. Levoglucosan (1,6-anhydro-β-D-glucopyranose) (LG) is an anhydrous sugar formed as a major product during pyrolysis of cellulose. LG might be a promising chemical platform. It can be converted to different high added-value chemicals such as levoglucosenone, 5-hydroxymethylfurfural and styrene directly or through a glucose intermediate via chemical, catalytic and biochemical processes. In this critical review we focus not only on the pyrolytic methods for the synthesis of levoglucosan, but above all also on the recent scientific progress in the chemical and biochemical transformation of levoglucosan to highly valued compounds. The catalytic performances of the heterogeneous and enzymatic catalytic systems used for different reactions of LG conversion are reviewed. Specific properties of the active sites, roles of additives, and solvents and conditions are discussed in detail. We conclude on recommendations to further improve LG conversion to high added-value products.

Continuous-flow chemistry is an enabling technology which offers great advantages when combined with green chemistry principles toward the development of a more sustainable chemical process. Herein, we present some of the developments made so far on the continuous-flow process that can help researchers to have a different view on how this technology can collaborate with green chemistry.

Enantiomerically pure alcohols and amines are important building blocks for the pharmaceutical and agrochemical industries. Among the different approaches to reach these compounds, enzyme-catalyzed kinetic resolution (EKR) of racemates is one of the most widely studied and employed methodologies. In this kind of reaction, the acyl donor plays an important role, making the search for new acylating agents an attractive field. Herein, we report our results over the use of PEG600 carboxylates as acylating agent for separation of amines and alcohols enantiomers in continuous flow. For the EKR of 1-phenylethylamine, PEG600-diester show the best results, and (S)-1-phenylethylamine was obtained with high yield and enantiomeric purity (49% yield and >99% (S)) with a productivity of 211 mg h−1 genzyme−1. (R)-1-phenylethylamine was recovered after chemical hydrolysis of the amide formed with high yield and ee (35% yield and 95% ee). In addition, the immobilized enzyme remains active for at least 20 h operation. On the other hand, (R)- and (S)-1-phenylethanol was obtained after continuous lipase-catalyzed hydrolysis of the ester (formed after reaction with PEG) in good conversions to both enantiomers, with a productivity of 68 mg h−1 g enzyme−1 for the (S)- enantiomer and 64 mg h−1 genzyme−1 for the (R) enantiomer.

Made available in DSpace on 2018-11-26T16:01:02Z (GMT). No. of bitstreams: 0 Previous issue date: 2018-09-01 Fundação de Amparo à Pesquisa do Estado do Rio de Janeiro (FAPERJ) Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Embrapa Cafe Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Cafestol and kahweol (C&K), two coffee diterpene alcohols with structural similarity which exhibit anticarcinogenic effects, were isolated from green coffee Arabica beans, followed by their lipase-catalysed esterification and purification by preparative high-performance liquid chromatography (HPLC). The isolation and enzymatic synthesis parameters of C&K esters were studied, with the latter optimised by a Central Composite Design; both procedures were monitored by gas chromatography. Scale up and improved isolation conditions resulted in 1.29 g of C&K, with 98% purity from 300 g of green Arabica beans. The highest C&K ester yields were observed using an alcohol: fatty acid molar ratio of 1:5, 73.3 mg mL(-1) of CAL-B enzyme, 70 degrees C and 240 rpm for 3 days in toluene, leading to 85-88% conversion among a variety of tested C&K esters, including n-C-14:0-C-20:0, C-18:1, C-18:2 and C-18:3. Univ Fed Rio de Janeiro, Inst Quim, Lab Anal Aromas, Ave Athos da Silveira Ramos 149,Bloco A,Sala 626, BR-21941895 Rio De Janeiro, RJ, Brazil Univ Fed Rio de Janeiro, Inst Quim, LADETEC, Ave Horacio Macedo 1281, BR-21941598 Rio De Janeiro, RJ, Brazil Univ Fed Rio de Janeiro, Escola Quim, Dept Engn Bioquim, Ave Athos da Silveira Ramos,Bloco E,Sala E203, BR-21941909 Rio De Janeiro, RJ, Brazil Univ Estadual Paulista, Dept Engn Bioproc & Biotecnol, Campus Botucatu,Rua Jose Barbosa de Barros 1780, BR-18610307 Lageado, SP, Brazil Monash Univ, Sch Chem, Australian Ctr Res Separat Sci, Wellington Rd, Clayton, Vic 3800, Australia Embrapa Agroind Alimentos, Ave Amer 29501, BR-23020470 Rio De Janeiro, RJ, Brazil Univ Fed Rio de Janeiro, Inst Quim, Lab Biocatalise & Sintese Organ, Ave Athos da Silveira Ramos 149, BR-21941895 Rio De Janeiro, RJ, Brazil Univ Estadual Paulista, Dept Engn Bioproc & Biotecnol, Campus Botucatu,Rua Jose Barbosa de Barros 1780, BR-18610307 Lageado, SP, Brazil

The decarboxylation of amino acids in presence of a carboxylic anhydride leading to the corresponding ketones, known as Dakin-West reaction, is about to complete almost one century of discovery. In this review, we firstly present the chronological progress in the mechanistic study of the reaction, with an overview about types of substrates, anhydrides and bases already used in the Dakin-West reaction. And ultimately, the application of the reaction in the synthesis of compounds of pharmaceutical or industrial interest is also discussed.

Crizotinib is an anti-cancer agent approved for treatment of non-small cell lung carcinoma. Retrosynthetic analysis revels 1-(2,6-dichloro-3-fluorophenyl)ethanol as an important intermediate, which can be made available by different biocatalytic approaches. Herein we report our results on the kinetic and dynamic resolution towards the desired chiral intermediate for Crizotinib synthesis. The results obtained show that very good conversions and high selectivity could be obtained for the kinetic resolution (45% conv. and E > 200) while dynamic kinetic resolution under continuous-flow conditions afforded the desired product in 57% conversion and 98% e.e.

Gliflozins are an important class of prescription drugs used to treat type II diabetes. They reduce blood sugar levels by targeting the sodium-glucose transport protein 2 (SGLT2) and consequently inhibit glucose reabsorption in the kidney. There are currently several FDA-approved gliflozins as well as others in the pipeline to be launched in the next few years. This review describes the synthetic strategies used for manufacturing SGLT2 inhibitors on both bench and industrial scales. Moreover, the drawbacks to the strategies and the improvements made to obtain selected gliflozins and their glucose derivatives over the years are highlighted.

In this work lipase CaLB was immobilized on functionalized Pd-SiO 2 nanoparticles in order to simplify the DKR of α-methylbenzylamine. Hybrid biocatalysts showed immobilization efficiencies of 82%, 80% and 76% when containing 1, 5 and 10% of Pd respectively. On DKR reaction values of ee > 99% and conversion of 82% were found with only 1% of Pd, generating a productivity of 2.21 mg of product h −1 mg of support −1 against 0.76 found by N435®. Compared to commercial N435®, the novel biocatalysts showed protein loads about 15-fold lower and higher activity, demonstrating competitive performances and high industrial applications.

In this perspective article, the use of continuous flow synthesis to prepare advanced pharmaceutical intermediates in developing economies is highlighted. Case studies are presented to suggest that cost effective local manufacture of life saving drugs, may potentially be implemented to facilitate better access to drugs to the underprivileged.

The asymmetric synthesis of serinol-derivatives was investigated employing different amine transaminases as biocatalysts. Under the optimized conditions conversions up to 92% and excellent enantiomeric excesses up to 99% ee were obtained providing access to both, the ( R )- and ( S )-configurations of the serinol-monoester (2-amino-3-hydroxypropyl hexanoate).

Herein we report a convenient, fast, and high-yielding method for the generation of the racemic amide anaesthetics mepivacaine, ropivacaine, and bupivacaine. Coupling of α-picolinic acid and 2,6-xylidine under sealed-vessel microwave conditions generates the intermediate amide after a reaction time of only 5 min at 150 °C. Subsequent reaction in a continuous-flow high-pressure hydrogenator (H-Cube ProTM) in the presence of the respective aldehyde directly converts the intermediate to the final amide anaesthetics in a continuous, integrated, multi-step ring-hydrogenation/reductive amination protocol. Merits and limitations of the protocol are discussed.

BACKGROUND In this work, lipase B from Candida antarctica (CaLB) was immobilized on Purolite® ECR8205F, Purolite® ECR8214F and Immobead® IB150 P epoxy resins with no modification to their surfaces. Biocatalysts were evaluated for thermal stability and applied in reactions of hydrolysis, esterification and the synthesis of glyceryl carbonate by transesterification with dimethyl-carbonate both with glycerol and Macauba oil as well as dynamic kinetic resolution of α-methylbenzylamine, all of them compared with commercial Novozyme 435®. RESULTS Protein desorption of the biocatalysts with Triton X-100 showed that lipase was immobilized by covalent single-bond type binding. The immobilization efficiencies were 55.1% for the biocatalyst 8205, 57.1% for 8214, and 14.9 for the 150P, demonstrating the intense effect of surface and material composition on lipase immobilization. The biocatalysts also showed higher initial velocities of esterification and hydrolysis reactions as well as higher thermal stability than Novozyme 435®. On glycerol carbonate synthesis, conversion of 97% and selectivity higher than 99% was demonstrated by enzyme 8214, similar to Novozyme 435®. On kinetic dynamic resolution, conversions higher than 94% and and enantiomeric excesses greater than 90% were also depicted. CONCLUSION Compared with commercial preparation Novozyme 435®, the novel biocatalysts obtained by immobilization on new epoxy resins demonstrated protein loads about 10-fold lower and higher specific activity. In all reactions performed, competitive performances were found, demonstrating high potential for industrial applications. © 2017 Society of Chemical Industry

Herein, we report a method for the continuous flow DKR of rac-1-phenylethanol catalyzed by CAL-B and VOSO4, using a single packed-bed containing both catalysts. Taking advantage of continuous flow techniques to circumvent compatibility issues, the DKR of rac-1-phenylethanol could be performed continuously to give enantiopure (R)-esters with excellent conversions and high productivities.

Dimethyl fumarate (DMF) is a methyl ester of fumaric acid and has recently gained attention due to its use as a pro-drug in different pharmaceutical preparations, besides the low price of the final molecule and no active patents being available for the synthesis of DMF, the prices of multiple sclerosis treatment are still high. In our continuous effort for the development of process intensification strategies towards the synthesis of active pharmaceutical ingredients, here we present our work on a cascade methodology for dimethyl fumarate synthesis in short reaction times and quantitative yields.

Every year, a large amount of residual agroindustrial waste has been generated and only around 10% is in fact reused. The development of new strategies for biomass valorization is important to add value to these commodities, since biomass is an excellent alternative feedstock to obtain chemicals of interest from renewable resources. The major compound of pyrolytic treatment of lignocellulosic biomass is levoglucosan (1,6-anhydroglucopyranose), an anhydro-sugar that can be transformed into glucose and is greatly valued in the most diverse industrial sectors as a surfactant, emulsifier, or even a lubricant. In this work, levoglucosan was acylated by lipase-catalyzed transesterification in acetonitrile with great conversions and selectivities with different acyl donors such as ethyl esters of lauric, palmitic, stearic, and oleic acids prepared in situ in an integrated strategy mediated by commercial lipases Novozym435 (N435), PSIM, and the home-made biocatalyst CaLB_epoxy. As a result, all biocatalyst generated mostly monoesters, with N435 being more selective to produce lauric esters (99% at 50&deg, C) and PSIM to produce oleic esters (97% at 55 &deg, C) while CaLB_epoxy was more selective to produce oleic esters of levoglucosan (83% at 55&deg, C). This is the first report in the literature on the production of high selectivity levoglucosan esters.

Two commercially available and widely used enzymes, the parent Thermomyces lanuginosus lipase (TLL) and the shuffled phospholipase A1 Lecitase (Lecitase Ultra), were encapsulated in AOT/isooctane reverse micelles and evaluated regarding their structure and activity. Preparations were also tested as effective biocatalysts. Small-angle X-ray scattering (SAXS), electronic paramagnetic resonance (EPR), and fluorescence spectroscopy were the techniques applied to assess the effects of enzyme incorporation to a reverse micellar nanostructure. SAXS analysis showed that the radius of gyration (Rg) changed from 16 to 38 Å, as the water content (w0) increased. Elongated shapes were more commonly observed than spherical shapes after enzyme encapsulation. EPR studies indicated that enzymes do not participate in the interface, being located in the aqueous center. Fluorescence energy transfer showed that TLL is located in the water core, whereas Lecitase Ultra is closer to the interface. Enzymatic activity toward a standard esterification reaction endured after the enzyme was incorporated into the micelles. The activity of TLL for systems with w0 15 showed the highest conversion yield, 38% in 2 h, while the system with w0 10 showed the highest initial velocity, 0.43 μM/min. This last system had a Rg of 19.3 Å, similar to that of the TLL monomer. Lecitase Ultra showed the highest conversion yields in systems with w0 10, 55% in 2 h. However, the initial rate was much lower than that of TLL, suggesting less affinity for the substrates, which is expected since Lecitase Ultra is a phospholipase. In summary, we here used several spectroscopic and scattering techniques to reveal the shape and stability of TTL and Lecitase Ultra encapsulated systems, which allowed the selection of w0 values to provide optimized enzymatic activity.

Several value-added products can be produced from glycerol and among these products glycerol carbonate (GC) has received much attention in recent years because of its physical properties and wide application in the chemical, pharmaceutical and food industries. As a continuation of our efforts to produce GC under environmentally acceptable conditions, we proposed a consecutive approach where lipase B from Candida antarctica was immobilized on Accurel MP1000 (CalBAcc) under continuous-flow conditions followed by glycerol carbonate production by a cascade process of triacylglycerol hydrolysis, biodiesel synthesis and esterification of the remaining glycerol with dimethyl carbonate towards GC production. Results of the immobilization of lipase B from Candida antarctica on a continuous-flow protocol demonstrated that a short residence time of 25 minutes could lead to 83% of protein loading. Screening of glycerol carbonate production in a packed bed reactor revealed that CalBAcc and N435 showed the best results of conversion and selectivity, with more selectivity by CalBAcc, that could lead to quantitative yields and excellent selectivities of the desired glycerol carbonate at residence times of 176 minutes when working with soybean and palm oil. Comparatively, the results obtained with CalBAcc were better than the ones with Novozym 435 since no full conversion was observed.

Biodiesel is a mixture of fatty acid alkyl esters with properties similar to petroleum-based diesel. Thus, biodiesel can be used as either a substitute for diesel fuel or, more commonly, in a fuel blend. Biodiesel production can be catalyzed with mineral acids or bases or enzymes. The use of real-time techniques for monitoring the reaction and evaluating the efficiency of the catalyst can be of great use for optimizing the reaction and monitoring the process. In the present work, an in-line real-time methodology was used to evaluate and compare the kinetics of a reaction catalyzed with homo (hydrochloric acid) and heterogeneous (the enzymes Novozym 435, Lipozyme RM, and Lipozyme TL) catalysts. The esterification of oleic acid with ethanol was used as the reaction model. The study used attenuated total reflexion/Fourier transform infrared (ATR/FT-IR) and a single partial least squares (PLS) regression model to evaluate the kinetics of the various catalysts, without multiple calibrations, with validation by GC–MS. Novozym 435, which showed complete conversion after 165 min, was the best catalyst for this reaction. Lipozyme RM and Lipozyme TL had inferior conversion after the same amount of time, in agreement with the literature. All enzymatic catalysts showed higher conversion than hydrochloric acid at the same reaction conditions.

Made available in DSpace on 2018-12-11T16:45:27Z (GMT). No. of bitstreams: 0 Previous issue date: 2016-01-01 Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Empresa Brasileira de Pesquisa Agropecuária Fundação de Amparo à Pesquisa do Estado do Rio de Janeiro (FAPERJ) The vegetal species Arachis repens, commonly known as peanut grass, was studied and, for the first time, we detected the presence of the bioactive compound trans-resveratrol (t -RSV). We compared the efficiency of three different methodologies (conventional maceration [CM], ultrasound-assisted extractions [UAE], and microwave-assisted extractions [MAE]) concerning total phenolics (TP) and resveratrol (t -RSV) content, followed by antioxidant activity (AA) evaluation. By CM, at 1 h, the highest RSV content (1.024 ± 0.036 mg/L) and, correspondingly, the highest DPPH capture (23.90 ± 0.04 %) were found. The TP contents, at 1 h, presented the highest value (27.26 ± 0.26 mg/g GAE). By the UAE, the maximum yields of TP (357.18 mg/g GAE) and RSV (2.14 mg/L), as well as, the highest AA (70.95%), were obtained by 5 min after a maceration pretreatment, on the solid-solvent ratio 1: 40 w/v. For MAE, a central composite rotatable design (CCRD) was applied followed by the FFD design in order to evaluate the statistical effects of four independent variables on the extraction of RSV. The optimal conditions established for obtaining the highest recovery (2.516 mg/g) were 20 min; 90% MeOH aq.; 120 rpm; 60°C; and solid-solvent ratio: 1: 35 w/v. Relevant correlations were established considering the TP and RSV contents, as well as the AA, corroborating obvious advantages of such techniques in terms of high extraction efficiency in shorter times. Laboratório de Micropropagação e Transformação de Plantas Cellular Biology Department State University of Rio de Janeiro Departamento de Engenharia de Bioprocessos e Biotecnologia Universidade Estadual Paulista (UNESP) Campus Botucatu Biocatalysis and Organic Synthesis Group Chemistry Institute Federal University of Rio de Janeiro Laboratório de Produtos Naturais e Ensaios Biológicos (LaProNEB) Pharmacy Faculty Department of Natural Products and Food Federal University of Rio de Janeiro Departamento de Engenharia de Bioprocessos e Biotecnologia Universidade Estadual Paulista (UNESP) Campus Botucatu

A catalyst free decarboxylative trichloromethylation of imines to afford different trichloromethyl sulfonyl and sulfinyl amines has been presented. Only DMSO as a solvent at room temperature was necessary to provide the corresponding products in good to high isolated yields. A highly diastereoselective version was carried out, leading to the sulfinylimine with good yield and near perfect diastereoselectivity. Regarding the reaction profile, ATR-FTIR spectroscopy was employed to support the entire mechanism and also to provide details on the trichloroacetate salts behavior against electrophiles and in the presence of different solvents.

O Crizotinibe é um agente anticancerígeno aprovado para tratamento de carcinoma de pulmão de células grandes. Segundo a análise retrossintética (FRANÇA e col., in press), o 1-(2,6-dicloro-3-fluorofenil) etanol é um intermediário importante, que pode ser produzido por diferentes abordagens biocatalíticas (CUI e col., 2011). Logo, o objetivo foi preparar este intermediário na sua forma enantiomericamente pura desejada. A metodologia usada foi a mesma do 1-feniletanol, descrita por Koning e col. (2011), que apresenta a estratégia de produção do álcool racêmico por redução clássica com borohidreto de sódio, seguida de acetilação via resolução cinética. Uma vez que o 1- (2,6-dicloro-3-fluorofenil) etanol contém substituintes nas posições orto, são esperados longos tempos de reação para esta transformação. Deste modo, deu-se início por rastrear a influência de doadores de acila (acetato de etila, acetato de vinila e o acetato de isopropenila) sobre o resultado da reação quando se utiliza a lipase comercial Novozyme 435 a 60 °C e ciclohexano como solvente com tempo reacional de 10 dias. Dentre os doadores de acila avaliados, o acetato de isopropenila levou aos melhores resultados, em boas conversões e alta seletividade (conv. 44%, 99% e.e.).

Monoacylglycerols (MAGs) are amphiphilic compounds with wide range of applications such as emulsifiers, solubility agents, and chiral building blocks. These compounds are currently produced by chemical approaches involving alkaline glycerolysis or esterification under high temperatures and pressure, resulting in low yields and with by-products. Lipase-catalyzed processes have been alternative tools to provide more ecological approaches since MAGs can be obtained under milder reaction conditions and with higher selectivity. However, just a few papers have been explored the potential of endophytic fungi as lipase sources. In this work we summarized the screening of lipolytic activity of endophytic fungus S. lycopersici and Sordaria spp isolated from vegetal species collected in Jurubatiba Sandbank National Park, RJ, Brazil, as well as its applications as biocatalysts on the lipase-catalyzed synthesis of solketal 1-MAG derivatives. As a result, the crude enzymatic extract of S. lycopersici showed 98 U/mL and 110 U/mL of hydrolytic activity after 72 h and 96 h, respectively, against 74 U/mL (96 h) and, 86 U/mL (120 h) expressed by enzymatic extract of Sordaria spp.. Concerning the esterification activity, both crude enzymatic extracts and lyophilized fungi showed about 80 % conversion into ethyl oleate, in 100 min. On solketal derived 1-MAG synthesis, S. lycopersici both lyophilized and immobilized in polyurethane (PU) forms showed more than 75 % of conversion in the presence and absence of organic solvents. On MAG recycle assays, the PU biocatalyst could be reused after five reaction cycles while for the ethyl oleate synthesis, PU biocatalyst could be reused after six reaction cycles. Both microorganisms, immobilized in polyurethane, were successfully applied as biocatalysts in esterification reactions for solketal 1-MAG derivative production, in a solvent-free media.