- Chemo- and Enzyme-Catalyzed Reactions Revealing a Common Temperature-Dependent Dynamic Solvent Effect on Enantioselectivity
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The enantiomeric ratio E of enzyme-catalyzed (Candida antarctica lipase and lipase PS) and chemocatalyzed (L-proline-based diamines) acylation reactions of 1-(naphthalen-2-yl)ethanol, 2-phenylpropanol, and 2-benzylpropane-1,3-diol is dependent on solvent and temperature. Plots of In E vs. 1/T showed the presence of inversion temperatures (Tinv). The Tinv values for the bio-catalyzed and the chemo-catalyzed reactions are fairly in agreement, and correspond as well to the TNMR values obtained by variable-temperature 13C-NMR experiments on the substrates in the same solvent of the resolution. This result demonstrates that clustering effects in the substrate solvation manage the chemical and the enzymatic enantioselectivity, and, moreover, that the solute-solvent cluster is always the real reacting species in solution for chemical as well as for enzymatic reactions.
- Cainelli, Gianfranco,Galletti, Paola,Giacomini, Daria,Gualandi, Andrea,Quintavalla, Arianna
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Read Online
- Design, asymmetric synthesis, and evaluation of pseudosymmetric sulfoximine inhibitors against HIV-1 protease
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The HIV-1 protease is a validated drug target for the design of antiretroviral drugs to combat AIDS. We previously established the sulfoximine functionality as a valid transition state mimetic (TSM) in the HIV-1 protease inhibitors (PI) design and have id
- Lu, Ding,Sham, Yuk Yin,Vince, Robert
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experimental part
p. 2037 - 2048
(2010/06/12)
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- Optically active N- and C-terminal building blocks for the synthesis of peptidyl olefin peptidomimetics
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Peptidyl olefin peptidomimetics serve as biologically active compounds or as intermediates for other peptidyl isosteres. The N-terminal side of the C=C bond could be easily prepared in an optically pure form from α-amino acids. Synthesis of C-terminal building blocks in an optically pure form is more challenging. We developed a chemoenzymatic stereoselective approach to such optically active C-terminal building blocks to be assembled into peptidyl olefins by a variety of reactions. They include an electrophilic aldehyde and nucleophilic sulfone, phosphonium salt, phosphonate, and diselenide. Key enzymatic hydrolysis of prochiral diesters to the corresponding hydroxy esters introduces optical activity. The sequence of the subsequent chemical reactions, either protection- hydrolysis-functionalization or functionalization-hydrolysis- protection, determines the absolute stereochemistry of the final building blocks.
- Mirilashvili, Sima,Chasid-Rubinstein, Naama,Albeck, Amnon
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body text
p. 4671 - 4686
(2010/10/19)
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- Chemoenzymatic synthesis of enantiomerically enriched α-chiral 3-oxy-propionaldehydes by lipase-catalyzed kinetic resolution and desymmetrization
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Enantiomerically enriched phenylalanine- and leucine aldehyde analogues have been prepared by lipase catalyzed desymmetrization or kinetic resolution of 1,3-propanediol derivatives as key steps. Observations of unusual enantioselectivity were made, and mo
- Wiktelius, Daniel,Larsson, Emma K.,Luthman, Kristina
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p. 2088 - 2100
(2007/10/03)
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- Asymmetric synthesis of homoisoflavanone using lipase-catalyzed reaction
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The (R)- and (S)-enantiomers of 3-benzyl-4-chromanone (homoisoflavanone) were synthesized starting with the optically active 2-benzyl-1,3-propanediol monoacetates, which were obtained via the lipase-catalyzed enantioselective reaction.
- Kawasaki, Masashi,Toyooka, Naoki,Matsui, Yoshinori,Tanaka, Akira,Goto, Michimasa,Kakuda, Hiroko,Kawabata, Shigeki,Kometani, Tadashi
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p. 761 - 765
(2007/10/03)
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- Sulfonic acid ester derivatives, method for production thereof and use thereof
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Novel and useful optical active 2-aralkyl-3-sulfonyloxy-1-propanol and 2-aralkyl-3-sulfonyloxypropionic acid are provided by using an optical active 2-aralkyl-3-acyloxy-1-propanol as a starting material. Furthermore, an optical active 2-aralkyl-3-thiopropionic acid, which is an important intermediate of enkephalinase inhibitor, is provided. According to the present invention, industrially useful optical active sulfonic acid ester derivatives can be provided.
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Page column 13
(2010/02/05)
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- Expanding the utility of proteases in synthesis: Broadening the substrate acceptance in non-coded amide bond formation using chemically modified mutants of subtilisin
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The strategy of combined site directed mutagenesis and chemical modification creates chemically modified mutants (CMMs) with greatly broadened substrate specificities. We have previously reported that the CMMs of subtilisin Bacillus lentus (SBL) are efficient catalysts for the coupling of both L- and D-amino acids. We now report that these powerful catalysts also allow amide bond formation between a variety of non-coded carboxylic acids, including β-alanine and β-amino homologues of phenylalanine, with both L- and D-amino acid nucleophiles. As a guide to enzyme efficiency, a hydrolysis assay indicating pH change has been employed. CMMs selected by this screen furnished higher yields of coupling products compared to the wild-type enzyme (WT). Furthermore, both WT and CMM enzymes allow highly stereoselective aminolysis of a meso diester with an amino acid amine. These results highlight the utility of CMMs in the efficient formation of non-coded amides as potential peptide isosteres.
- Khumtaveeporn, Kanjai,Ullmann, Astrid,Matsumoto, Kazutsugu,Davis, Benjamin G.,Jones
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p. 249 - 261
(2007/10/03)
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- New asymmetric synthesis of dexecadotril and ecadotril starting from a single precursor
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We describe herein a method providing access to both enantiomers of 3-acetylthio-2-benzylpropionic acid via enzymatic desymmetrization of 2-benzyl-1,3-propanediol. These compounds are respectively the starting materials for the synthesis of ecadotril, and dexecadotril, which are powerful inhibitors of NEP (EC 3.4.24.11) and have been developed as therapeutic agents.
- Monteil,Danvy,Plaquevent,Duhamel,Duhamel,Gros,Schwartz,Lecomte
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p. 211 - 218
(2007/10/03)
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- Lipase-based HPLC stationary phase: Enantioselective synthesis of 2- substituted 1,3-propanediol monoacetates
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Pseudomonas cepacia lipase (PCL) has been immobilized by coating the enzyme on an epoxysilica HPLC column. The biocatalyst has been successfully used for the preparation of both the enantiomers of 3-acetoxy-2-benzyl- propan-1-ol and of 3-acetoxy-2-methylpropan-1-ol. The immobilized enzyme is active after months of use either in aqueous or in organic media. (C) 1999 Elsevier Science Ltd.
- Bertucci, Carlo,Petri, Antonella,Felix, Guy,Perini, Benedetta,Salvadori, Piero
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p. 4455 - 4462
(2007/10/03)
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- Synthesis of asymmetrized 2-benzyl-1,3-diaminopropane by a chemoenzymatic route: A tool for combinatorially developing peptidomimetics
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Both enantiomers of monoacetamide 5, together with 'dipeptides' 30a,b and monocarbamates 24, (R)-43 and (S)-43, all derived from 2-benzyl-1,3- diaminopropane 4, were synthesized by a chemoenzymatic route starting from the known monoacetate 12. The behaviour of 4 and of the bis(acylated) derivatives 8-11 with respect to hydrolytic enzymes is also presented, together with an extensive study on the configurational stability of monoacylated derivatives of 4.
- Banfi, Luca,Guanti, Giuseppe,Riva, Renata
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p. 3571 - 3592
(2007/10/03)
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- Prediction of the solvent dependence of enzymatic prochiral selectivity by means of structure-based thermodynamic calculations
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A new, quantitative model is elaborated to rationalize the solvent dependence of enzymatic selectivity solely on the basis of the thermodynamics of substrate solvation. The model predicts that any type of the selectivity (defined as the ratio of k(cat)/K(
- Ke,Wescott,Klibanov
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p. 3366 - 3374
(2007/10/03)
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- N-substituted acylamino acid compounds, process for their production and their use
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The present invention provides an N-substituted acylamino acid compound of the formula: STR1 a process for their production and pharmaceutical uses, and intermediates useful for their production.
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- An efficient enantioselective preparation of 2-substituted-3-hydroxypropionic acids via chemo-enzymatic reaction
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The key intermediates, 2-substituted-3-hydroxypropionic acids 1, of the potent renin inhibitors were synthesized enantioselectively starting from 2-substituted-1,3-propanediols via chemo-enzymatic reaction.
- Atsuumi, Shugo,Nakano, Masato,Koike, Yutaka,Tanaka, Seiichi,Ohkubo, Mitsuru,Yonezawa, Toshiko,Funabashi, Hiroshi,Hashimoto, Junko,Morishima, Hajime
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p. 1601 - 1604
(2007/10/02)
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- LIPASE-CATALYZED ASYMMETRIC SYNTHESIS OF CHIRAL 1,3-PROPANEDIOLS AND ITS APPLICATION TO THE PREPARATION OF OPTICALLY PURE BUILDING BLOCK FOR RENIN INHIBITORS
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Asymmetric synthesis of chiral 2-substituted-1,3-propanediols was realized the lipase-catalyzed transesterification in vinyl acetate and it was applied to the synthesis of an optically active sulfone derivate.
- Tsuji, Keiichiro,Terao, Yoshiyashu,Achiwa, Kazuo
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p. 6189 - 6192
(2007/10/02)
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- Preparative Bioorganic Chemistry, XI. - Preparation of the Enantiomers of Paraconic Acid Employing Lipase-Mediated Asymmetric Hydrolysis of Prochiral Diacetates as the Key Step
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(S)-(-)-Paraconic acid (1) was prepared from 2-(acetoxymethyl)-3-phenylpropyl acetate (4) by its asymmetric hydrolysis with pig pancreatic lipase as the key step.Similarly, (R)-(+)-1 was prepared from 2-(acetoxymethyl)-4-pentenyl acetate (2) by its asymme
- Mori, Kenji,Chiba, Naoki
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p. 957 - 962
(2007/10/02)
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- SYNTHESIS OF BOTH ENANTIOMERIC FORMS OF 2-SUBSTITUTED 1,3-PROPANEDIOL MONOACETATES STARTING FROM A COMMON PROCHIRAL PRECURSOR, USING ENZYMATIC TRANSFORMATIONS IN AQUEOUS AND IN ORGANIC MEDIA
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A direct entry to both enantiomeric forms c and ent-c based on enzyme catalyzed transformations of prochiral compounds of type a and b is described.The catalysts used are carboxyl esterase preparations obtained from crude porcine pancreas lipase.
- Tombo, G. M. Ramos,Schaer, H.-P.,Busquets Fernandez I,Ghisalba, O.
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p. 5707 - 5710
(2007/10/02)
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