The Diels–Alder adduct (6), prepared from 4a,9a-epoxy-4a,9a-dihydroanthracene-1,4,9,10-tetraone (3) and 1-methoxy-3-trimethylsilyloxybuta-1,3-diene, can be efficiently converted into the title compound (2b), a precursor of 4-demethoxydaunomycin (1d), by a five-step sequence.
由4a,9a-环氧-4a,9a-二氢
蒽-1,4,9,10-四酮(3)和1-甲氧基-3-三甲基甲
硅烷基氧基丁1,3-二烯制得的Diels–Alder加合物(6),通过五步序列,可以将其有效地转化为标题化合物(2b),其为4-脱甲氧基
道诺霉素(1d)的前体。