Aspergillus niger mediated a-hydroxylation of cyclic ketones

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2006

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Karabacak, Elife Özlem

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Chiral a -hydroxy ketones are important structural units in many natural products, biologically active compounds and the hydroxyl group has frequently been used as a reagent directing group, such as for the selective elaboration of aldol products. In this work, enzymatic synthesis of both enantiomers of the a -hydroxy ketones (2-hydroxy indanone, 2-hydroxy tetralone) using Aspergillus niger by selective α-oxidation of ketones (1-indanone, 1-tetralone) was studied. The α-oxidation of ketones was carried out by using whole cells of Aspergillus niger in different growth media. A. niger whole cell catalyzed reactions afforded (S)-configurated 2- hydroxy-1-tetralone with %87 e.e. in DMSO at pH 5.0. In addition to this,while (S)-configurated 2-hydroxy-1-indanone with %33 e.e. in pH 8.0 (in DMSO) was synthesized, (R)-configurated-2-hyroxy-1-indanone with %32 e.e. in pH 7.0 ( in DMSO) was synthesized.

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Biotechnology.

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http://etd.lib.metu.edu.tr/upload/3/12608088/index.pdf
https://hdl.handle.net/11511/16485

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Graduate School of Natural and Applied Sciences, Thesis

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Citation Formats

E. Ö. Karabacak, “Aspergillus niger mediated a-hydroxylation of cyclic ketones,” M.S. - Master of Science, Middle East Technical University, 2006.