- Novel and efficient chemoenzymatic synthesis of D-glucose 6-phosphate and molecular modeling studies on the selective biocatalysis
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A concise chemoenzymatic synthesis of glucose 6-phosphate is described. Candida rugosa lipase was found to be an efficient catalyst for both regio- and stereoselective deacetylation of the primary hydroxy group in the peracetylated D-glucose. In addition, we report an improved synthesis of 1,2,3,4,6-penta-O- acetyl-α-D-glucopyranose providing a large-scale procedure for the acetylation of α-D-glucose without isomerization at the anomeric center. The high overall yield and the easy scalability makes this chemoenzymatic strategy attractive for industrial application. Furthermore, molecular modeling of phosphonate transition-state analog for the enzymatic hydrolysis step supports the substrate selectivity observed with Candida rugosa lipase. Wiley-VCH Verlag GmbH & Co. KGaA, 2007.
- Rodriguez-Perez, Tatiana,Lavandera, Ivan,Fernandez, Susana,Sanghvi, Yogesh S.,Ferrero, Miguel,Gotor, Vicente
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p. 2769 - 2778
(2008/03/13)
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- Regio-selective deprotection of peracetylated sugars via lipase hydrolysis
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Purified lipases (via interfacial activation on hydrophobic supports) from different microbial extracts have been evaluated in the regio-selective hydrolysis of peracetylated sugars (peracetylated glucose, ribose and sucrose). Among the enzymes tested, lipases from Candida rugosa (CRL) and from Pseudomonas fluorescens (PFL) exhibited the best properties in these reactions. Then, we have prepared two different immobilized lipase preparations obtained by interfacial activation on hydrophobic supports or by covalent attachment on glutaraldehyde agarose. Interfacially activated lipases exhibited a higher activity than covalently attached enzymes (even by a 100-fold factor), giving the higher yields of mono deacetylated sugars (in some instances by more than a threefold factor) in short reaction times. In the hydrolysis of 1,2,3,5-tetra-O-acetyl-β-D-ribofuranose catalyzed by PFL adsorbed on octyl agarosa, hydrolyzed mainly the 3 position (30% of yield) while the CRL gave the hydrolysis only in position 5 (about 50% of yield). Depending on the enzyme immobilized preparation, we have been able also to obtain selective hydrolysis of 1,2,3,4,6-penta-O-acetyl-α/β-D-glucopyranose obtaining a free hydroxyl group in position 1, 4 or 6. Moreover, selective hydrolysis in the 4′ position of peracetylated sucrose was achieved when the hydrolysis is performed with CRL immobilized on octyl-agarose (yield was 77%).
- Fernandez-Lorente, Gloria,Palomo, Jose M.,Cocca, Jany,Mateo, Cesar,Moro, Paola,Terreni, Marco,Fernandez-Lafuente, Roberto,Guisan, Jose M.
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p. 5705 - 5711
(2007/10/03)
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- Regioselective hydrolysis of peracetylated α-D-glucopyranose catalyzed by immobilized lipases in aqueous medium. A facile preparation of useful intermediates for oligosaccharide synthesis
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Penta-O-acetyl-α-D-Glucopyranose was selectively deacetylated in aqueous media by lipases from Candida cilindracea (CCL) adsorbed on octyl- agarose support. Enzymatic hydrolyses was regioselective at the 4-position under neutral pH and towards the 6 position under acidic conditions. This enzymatic approach allows the one step synthesis of 1,2,3,6-tetra-O-acetyl- α-D-glucopyranoses 1, a useful intermediate in oligosaccharide synthesis.
- Bastida, Agatha,Fernandez-Lafuente, Roberto,Fernandez-Lorente, Gloria,Guisan, Jose M.,Pagani, Giuseppe,Terreni, Marco
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p. 633 - 636
(2007/10/03)
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- Syntheses and 1H- and 13C-Nuclear Magnetic Resonance Spectra of All Positional Isomers of Tetra-O-acetyl-D-glucopyranoses, and Their Monobenzyl and Monotrityl Derivatives
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All the isomers of the tetra-O-acetyl-D-glucopyranoses, and their monobenzyl and monotrityl derivatives were synthesized and systematic 1H- and 13C-nuclear magnetic resonance (1H- and 13C-NMR) studies were carried out.Complete assignments of the 1H- and 13C-NMR signals were achieved by 1H- and 13C-decoupling techniques and by the use of a shift reagent and changes of solvents.Moreover, when necessary, 1H- and 13C-shift-correlated 2D NMR spectroscopy at higher frequency (Bruker AM 400) was applied.The shifts on deacetylation, benzylation, and tritylation were estimated on the basis of the 1H- and 13C-chemical shifts of these compounds, and the effects of deacetylation and benzyl- or trityl-substitution are discussed.Keywords - tetra-O-acetyl-D-glucopyranose; monobenzyl tetra-O-acetyl-D-glucopyranose; monotrityl tetra-O-acetyl-D-glucopyranose; 1H-NMR; 13C-NMR; deacetylation shift; benzylation shift; tritylation shift
- Utamura, Toshiko,Kuromatsu, Keiko,Suwa, Kiyoko,Koizumi, Kyoko,Shingu, Tetsuro
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p. 2341 - 2353
(2007/10/02)
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