Bioorganic syntheses

Epoxyfarnesol was first prepared by van Tamelen, Stomi, Hessler, and Schwartz 4 using essentially this procedure. It is based on the findings of van Tamelen and Curphey5 that N-bromosuccinimide in a polar solvent was a considerably more selective oxidant than others they tried. This method has been applied to produce terminally epoxidized mono-, sesqui-, di-, and triterpene systems for biosynthetic studies and bioorganic synthesis.6 It has also been applied successfully in a simple synthesis of tritium-labeled squalene [2,6,10,14,18,22-Tetracosahexaene, 2,6,10,15,19,23-hexamethyl-, (all-E)-] and squalene-2,3-oxide [Oxirane, 2,2-dimethyl-3-(3,7,12,16,20-pentamethyl-3,7,ll,-15,19-heneicosapentaenyl)-, (all-E)-],7 and in the synthesis of Cecropia juvenile hormone.8... 

New insights into the analysis of hydrophobically post-translational modified proteins could be achieved by the construction of lipidated proteins in a combination of bioorganic synthesis of activated lipopeptides and bacterial expression of the protein backbone (Fig. 19). The physico-chemical properties of such artificial lipoproteins differ substantially from those of the corresponding lipopeptides. The pronounced dominance of the hydrophilic protein moiety (e.g., for the Ras protein 181 amino acids) over a short lipopeptide with one or two hydrophobic modifications provides solubility up to 10 4 mol/1, while the biotinylated or fluorescence labeled lipopeptides exhibit low solubility in aqueous solutions and can be applied in the biophysical experiments only in vesicle integrated form or dissolved in organic solvent. 

Bioorganic Synthesis of Ras Proteins for the Study of Signal Transduction, B. Bader, K. Kuhn, D. J. Owen, H. Waldmann, A. Wittinghofer, J. Kuhlmann, Nature 2000, 403, 223-226. 

Enantioselective C-C bond formation is gaining more and more importance in bioorganic synthesis. This reaction is efficiently catalyzed by 2-ketoacid decarboxylases (E.C. 4.1.l.X) as well as by hydroxynitrile lyases (E.C. 4.1.2.X). 

The project encompassed the comparative characterization of pyruvate decarboxylase from Z. mohilis (PDC) and benzoylformate decarboxylase from P. putida (BED) as well as their optimization for bioorganic synthesis. Both enzymes require thiamine diphosphate (ThDP) and magnesium ions as cofactors. Apart from the decarboxylation of 2-ketoacids, which is the main physiological reaction of these 2-ketoacid decarboxylases, both enzymes show a carboligase site reaction leading to chiral 2-hydroxy ketones (Scheme 2.2.3.1). A well-known example is... 

An asset of the Aachen/Jiilich bioorganic synthesis approach is technology transfer, which is testified by no less than five start-up companies. Scale-up requires stable and highly efficient enzymes as well as appropriate reaction technology. The development of membrane reactors has been a key to success. Reaction technology is outlined by C. Wandrey and co-workers in the final article. 

N. L. Klyachko, A. V. Levashov, (Bioorganic synthesis in reverse micelles and related systems) Curr. Opin. Colloid Interface Sci. 2003, 8,179-186. 

Brussee J, Roos EC, Van der Gen A (1988) Bioorganic synthesis of optically active cyanohydrins and acyloins. Tetrahedron Lett 29 4485 1488... 

Bader B, Kuhn K, Owen DJ, Waldmann H, Wittinghofer A, Kuhlmann J. Bioorganic synthesis of lipid-modified proteins for the study of signal transduction. Nature 2000 403 223-226. 

Sears, R. and Wong, C. H., Engineering enzymes for bioorganic synthesis peptide bond formation, Biotechnol Prog., 12, 423 33, 1996. 

Stasinska B, Danielsson B and Mosbach K 1989 The use of biosensors in bioorganic synthesis peptide synthesis by immobilized a-chymotrypsin assessed with an enzyme thermistor Biotechnol. Tech. 3 281-8 Danielsson B and Larsson P-0 1990 Specific monitoring of chromatographic procedures Trends Anal. Chem. 9 223-7... 

This book is particularly useful to those without a strong background in chemical engineering and gives a very clear exposition (with easily understandable mathematics) of biokinetics, dynamic differential balances, and modeling of a number of reactions and reactor types normally encountered in bioorganic synthesis. 

Bioorganic Synthesis Engineering 655 Table 20.4 Linearized forms of the Michaelis-Menten equation... 

Turner APF, Aston WJ, Higgins IJ, Davis G, Hill HAO. Applied aspects of bioelectrochemistry fuel cell, sensors, and bioorganic synthesis Biotechnol Bioeng Symp 1982 12 401 12. 

Reidel, A. Waldmann, H. Enzymatic Protecting Group Techniques in Bioorganic Synthesis. J. Prakt. Chem. 1993, 335, 109-127. 

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