A ketene [2 + 2]-addition, an intramolecular aldol reaction, a Suzuki–Miyaura coupling, and a chemoselective lactam reduction were used to prepare a late-stage precursor of haouamine A. Exposure to acid led to a Grob-type fragmentation of the strained 3-aza[7]paracyclophane ring, followed by a tandem Pictet–Spengler reaction of the intermediate iminium ion and conversion to a novel 1,4a-propanocyclopenta[b]pyridine
烯酮[2 + 2]加成,分子内醛醇缩合反应,Suzuki-Miyaura偶联和
化学选择性内酰胺还原被用于制备花
甲胺A的后期前体。暴露于酸中会导致Grob型碎裂应变后的3-氮杂[7]对环环烷环,随后是中间
亚胺离子的串联Pictet-Spengler反应,并转化为新型的1,4a-丙环戊[ b ]
吡啶。该级联反应也可能与
天然产物的作用机理有关。