The aromatic yohimboid indole alkaloid oxogambirtannine (9) was synthesized in high yield via the intramolecular [4 + 2] cycloaddition/dehydrogenation of the substituted β-carboline 13, which was readily accessed by the reaction of 10 with the acid chloride 11 in the presence of the diene 12. In a similar manner the prototypical protoberberine skeleton 20 was rapidly constructed upon cyclization of
通过取代的β-咔啉13的分子内[4 + 2]环加成/脱氢反应,高收率合成了芳香族
育亨宾吲哚生物碱oxambiambirtannine(9),在存在的情况下10与酰基
氯11的反应很容易获得。二烯12。以类似的方式,在取代
异喹啉17环化后,快速构建原型小ber碱骨架20。