Synthesis directed towards putative advanced intermediates in sarubicin A biosynthesis
作者:Steven J. Gould、Rodney L. Eisenberg、Larry R. Hillis
DOI:10.1016/s0040-4020(01)89723-4
日期:1991.8
and formylated at C-5 to give 18. A hetero-Diels-Alder reaction with Danishefsky's diene and 18 was effected with the aid of sonication and ZnCl2, yielding a model, 20, for a putative C-glycoside intermediate in the biosynthesis of sarubicin A, 1. However, when 18 and the triethylsiloxydiene derived from 3-penten-2-one were treated under the same conditions no reaction occurred, while p-dimethylaminobenzaldehyde
合成了3,6-二羟基蒽酰胺5和其5-丙基衍生物15。发现前者非常不稳定,而后者则稳定并且可以可逆地氧化为类似的醌。3,6-二甲氧基蒽酰胺被保护为丙酮乙缩醛,并在C-5甲酰化,得到18。借助超声处理和ZnCl 2与Danishefsky's diene和18进行的杂Diels-Alder反应,产生了20的模型,用于建立沙比霉素A 1的生物合成中的C-糖苷中间体。但是,当18在相同条件下处理与3-戊烯-2-酮衍生的三乙基甲硅烷氧基二烯没有反应发生,而对-二甲基氨基苯甲醛仅产生醛醇产物23。