Selective Modifications of Hydrophobic Vitamin B12 Derivatives at c-and d-Positions
journal contributionposted on 19.08.2011, 00:00 by Keith ó Proinsias, Maciej Giedyk, Rafał Loska, Mikołaj Chromiński, Dorota Gryko
The acid-sensitivity of vitamin B12 derived mono- and diamides was studied. It was found that the use of reductive ring-opening of the lactone moiety deactivated undesired decomposition of c-mono- and c,d-diamides under acidic conditions. As a result, reactions gave respectively c- or d-acids which were further functionalized via coupling with amino acids. Though mono- and diamides exhibited acid sensitivity, they were used for the preparation of several highly functionalized molecules showing their stability under various reaction conditions.