Synthesis of 3''-Dehydro-4-O-methylbarminomycin II Having an Eight-membered Acetal-azomethine Ring
Barminomycin I and II, an extremely potent antitumor anthracyclines, have a unique eight-membered azomethine or carbinolamine structure. (1''R,5''R)-3''-Dehydro-4-O-methylbarminomycin II was first synthesized through the hypothetical biogenetic intermedia