Toluene dioxygenase (TDO)-catalysed benzylic hydroxylation of indene substrates (8, 16 and 17), using whole cell cultures of Pseudomonas putida UV4, was found to yield inden-1-ol (14 and 22) and indan-1-one bioproducts (15 and 23). The formation of these bioproducts is consistent with the involvement of carbon-centred radical intermediates. TDO-catalysed oxidation of indenes 8 and 16 also gave cis-diols 13 and 18 respectively. TDO and naphthalene dioxygenase (NDO), used as both whole-cell preparations and as purified enzymes, were found to catalyse the benzylic hydroxylation of chromane 30, deuteriated (+/-)-chromane 30(D) and enantiomers (4S)-30(D) and (4R)-30(D) to yield (4R)- and (4S)-chroman-4-ols 31/31(D) respectively. The mechanism of benzylic hydroxylation of chromane 30/30(D) involves the stereoselective abstraction of a pro-R (with TDO) or a pro-S (with NDO) hydrogen atom at C-4 and a marked preference for retention of configuration.
ASJC Scopus subject areas
- Biochemistry, Genetics and Molecular Biology(all)
Boyd, D., Sharma, N., Bowers, N. I., Boyle, R., Harrison, J. S., Lee, K., Bugg, T. D. H., & Gibson, D. T. (2003). Stereochemical and mechanistic aspects of dioxygenase-catalysed benzylic hydroxylation of indene and chromane substrates. Organic and Biomolecular Chemistry, 1(8), 1298-1307. https://doi.org/10.1039/b300898c