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Published on: August 19, 2012
Biocatalysed halogenation of nucleobase analogues
Rosario Médici1, Juan Ignacio Garaycoechea, Lucas Andrés Dettorre
1Biotransformation Laboratory, Universidad Nacional de Quilmes, R. S. Peña 352 Bernal, 1876 Buenos Aires, Argentina.
Abstract:
The synthesis of halogenated nucleosides and nucleobases is of interest due to their chemical and pharmacological applications. Herein, the enzymatic halogenation of nucleobases and analogues catalysed by microorganisms and by chloroperoxidase from Caldariomyces fumago has been studied. This latter enzyme catalysed the chlorination and bromination of indoline and uracil. Pseudomonas, Citrobacter, Aeromonas, Streptomyces, Xanthomonas, and Bacillus genera catalysed the chlorination and/or bromination of indole and indoline. Different products were obtained depending on the substrate, the biocatalyst and the halide used. In particular, 85% conversion from indole to 5-bromoindole was achieved using Streptomyces cetonii.
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