O-Debenzylation of a Pyrrolo[2,1-c][1,4]benzodiazepine in the Presence of a Carbinolamine Functionality: Synthesis of DC-81
17 September 2002 (online)
In contrast to other methods of reduction, catalytic transfer hydrogenation allows debenzylation of a phenolic hydroxyl in a carbinolamine-containing pyrrolo[2,1-c][1,4]benzodiazepine, while leaving the biologically-important carbinolamine moiety intact. This has been demonstrated by synthesis of the naturally occurring anti-tumour antibiotic DC-81 (10). An efficient synthesis of 4-benzyloxy-5-methoxy-2-nitrobenzoic acid (5), an important intermediate in the production of certain pyrrolobenzodiazepine antitumour agents, is also reported.