Enzyme-catalysed polyoxygenation of arenes and cis-diol derivatives

ORGN 135

Stuart T McGregor, stmg2000@hotmail.com, Derek R Boyd, dr.boyd@qub.ac.uk, Narain D Sharma, n.sharma@qub.ac.uk, Tayeb Belhocine, belhocinet@hotmail.com, and Christopher. C. R. Allen. School of Chemistry, Queen's University Belfast, David Keir Building, Stranmillis Road, Belfast BT9 5AG, United Kingdom
We, and collaborating laboratories, have shown that polycyclic aromatic hydrocarbons (PAHs), e.g. anthracene, phenanthrene, chrysene, are metabolised by dioxygenases to yield enantiopure mono-cis-dihydrodiols. A new class of metabolite (bis-cis-dihydrodiols) containing four chiral centres, due to tetrahydroxylation on one face, was isolated from chrysene. Our objective was to find further evidence of this enzyme-catalysed tetraoxygenation process to yield other PAH members of this new class e.g. anthracene and phenanthrene. Further objectives include improving the stability and yield of both bis-cis-diols by formation of cis-tetrahydrodiol and acetonide derivatives of the first generation cis-dihydrodiol metabolites as substrates for a mutant strain of Sphingomonas yanoikuyae containing biphenyl dioxygenase. The isolation of bis-cis-diols from anthracene and phenanthrene has been achieved using enantiopure cis-diol substrates. The yield and stability of the bis-cis-dihydrodiols has been improved upon by the use of tetrahydrodiol and acetonide substrates. The structure and absolute configurations of these new metabolites have been determined.