cross-coupling of the resulting 1-iodoisoquinolines to methyl 2-(isoquinolin-1-yl)benzoates and intramolecular acylation of the corresponding carboxylic acids with Eaton's reagent afforded five alkaloids of the oxoisoaporphine type. The yield of the cyclization step strongly depends on the electrophilic properties of ring B. An alternative cyclization protocol via directed remote metalation of ester and amide
可通过在C-1处烷氧基取代的
异喹啉的直接环
金属化,然后与
碘反应,方便地制备氧代
异阿扑吗啡生物碱。随后,将所得的
1-碘异喹啉与2-(
异喹啉-1-基)
苯甲酸甲酯进行Suzuki交叉偶联,并用Eaton试剂将相应的
羧酸分子内酰化,得到五个氧代异
吗啡碱类型的
生物碱。环化步骤的收率在很大程度上取决于环B的亲电性能。对酯和酰胺中间体的定向远程
金属化进行的另一种环化方案进行了深入研究,但发现不可行。其中两种
生物碱对HL-60肿瘤
细胞系显示出强大的细胞毒性。