Electrochemical reduction of desmycosin, structure investigation and antibacterial evaluation of the resulting products

Electrochemical reduction of desmycosin at the mercury electrode in aqueous medium was investigated by cyclic voltammetry and preparative scale electrolysis was carried out for the isolation and identification of products. Structure analyses of the resulting products were accomplished by MS, 1D and 2D NMR spectroscopy. The results obtained show that dimerization and two electron reduction of desmycosin occur in parallel yielding a symmetric dimer at position C13 and 10,11-dihydrodesmycosin as the end products. 10,11-dihydrodesmycosin shows decreased antibacterial activity in vitro in comparison with desmycosin, while the dimer is inactive.