Glycosylated Eumelanin Building Blocks by Thioglycosylation of 5,6‐Diacetoxyindole with an Expedient Selenium‐Based Dynamic‐Mixture Methodology

Abstract

AbstractA series of 3‐thioglycosylated 5,6‐diacetoxyindole derivatives, which are important tools for eumelanin research and application, were prepared through a practical and efficient approach exploiting a dynamic mixture of thioglycoside agents. The strategy is feasible for installing both mono‐ and disaccharide units and relies on the facile in situ conversion of glycosyl disulfides into the corresponding, more reactive, phenylselenenyl sulfides in the presence of diphenyl diselenide, N‐bromosuccinimide (NBS) and tetrabutylammonium bromide (TBAB).