We have worked out a very short approach to 1-oxoisoquinoline alkaloids starting from readily available 2-bromobenzamides utilizing 2-ethoxyvinylboronate as a C₂ building block for introduction of the C-3,C-4 unit of the isoquinoline core. TFA-mediated cyclization of crude ortho-ethoxyvinyl benzamides gave 1-oxoisoquinolines in one single operation. Further modifications of these compounds opened an access to the other chemotypes. In total, 14 alkaloids from four chemotypes (five 1-oxoisoquinolines, six 1-oxo-3,4-dihydroisoquinolines, one 1,3,4-trioxoisoquinoline, and two dimeric isoquinoline alkaloids) were obtained in this investigation. With this approach we improved the total syntheses of the monomeric oxoisoquinolines, and worked out the first total syntheses of the dimeric alkaloids berbanine and berbidine.

我们已经从使用2-乙氧基乙烯基硼酸酯作为C ₂构件引入异氰酸喹啉核心的C ₂结构单元的现成的2-溴苯甲酰胺开始，制定了一种非常短的1-氧异喹啉生物碱方法。TFA介导的原邻环化-乙氧基乙烯基苯甲酰胺在一次操作中得到1-氧代异喹啉。这些化合物的进一步修饰打开了进入其他化学型的途径。在这项研究中，总共获得了来自四种化学型的十四种生物碱（五种1-氧代异喹啉，六种1-氧代-3,4-二氢异喹啉，一种1,3,4-三氧代异喹啉和两种二聚异喹啉生物碱）。通过这种方法，我们改进了单体氧代异喹啉的总合成，并计算出了二聚生物碱小ban碱和苯达比定的第一批总合成。