Biotransformation of β-hydroxyphenyl selenides, diphenyldiselenide and benzeneseleninic acid by whole cells of Aspergillus terreus

Abstract

Aspergillus terreus CCT 3320 and A. terreus URM 3571 catalysed the biotransformations of organic β-hydroxyphenyl selenides through oxidation and methylation reactions. The kinetic resolution of ( RS)-1-(phenylseleno)-2-propanol ( 1) via enantioselective oxidation produced (+)-( S)- 1 in high enantiomeric excess (>99%) and in a yield of 50% as determined by product isolation. Oxidation of the R-enantiomer of 1, followed by elimination of the propyl moiety and subsequent methylation of the presumed intermediate, led to the formation of methylphenyl-selenide, which was isolated in a yield of 40%. Whole cells of A. terreus also biocatalysed transformations of diphenyldiselenide, benzeneseleninic acid, ( RS)-1-(phenylseleno)-2-pentanol and ( RS)-1-(phenylseleno)-3-methyl-2-butanol, but not of ( RS)-1-(phenylseleno)-2-phenyl-methanol. This is the first report of the biomethylation of organoselenium compounds by whole cells of A. terreus.