The synthesis of (±)-crispine A in 9 steps and 24% overall yield was achieved using a nitrosoalkene hetero-Diels-Alder addition to ethyl vinyl ether as the key step. The synthesis starts from commercial 3,4-dimethoxyphenylacetic acid and uses simple methods, easily accessible materials and inexpensive reagents. An isochroman derivative was unexpectedly formed in an attempted reduction of a dihydro-4H-1
使用亚乙基烯烃杂-Diels-Alder加成乙基
乙烯基醚作为关键步骤,可分9个步骤合成(±)-crispine A,总产率为24%。合成从商业3,4-二
甲氧基苯基
乙酸开始,并使用简单的方法,易于获得的材料和廉价的试剂。试图还原二氢-4 H -1,2-恶嗪中间体时,出乎意料地形成了
异色满衍
生物。
生物碱-
天然产物-全合成-杂Diels-Alder反应-氢化