Laccase-­catalyzed Dimerization of Phenolic Glucosides

A bio-catalyzed synthetic entry to novel dimeric derivatives of phenolic glucosides by laccase-mediated oxidative couplings, has been investigated. A number of glucosides, subjected to the action of these blue-copper oxidases, gave diasteromeric dimeric products, which were successfully isolated and characterized. When required, the sugar moieties were removed via a facile and reliable deglucosilation protocol based on the action of suitable glucosidases, obtaining the dimers of the corresponding non-glucosilated phenols as enantiomerically enriched species. To further explore the possibility of using these biocatalytic couplings in intramolecular processes, some phenolic glycosides were linked via lipase-catalyzed transesterifications reactions with activated diester derivatives of dicarboxylic acids. The obtained 'homodimeric' substrates were submitted to laccase-mediated oxidative coupling and the products characterized.