Graduate School of Pharmaceutical Sciences, Kyoto University, Yoshida, Sakyo-ku, Kyoto 606-8501, Japan.
Chemistry. 2011 Jan 10;17(2):626-33. doi: 10.1002/chem.201002287. Epub 2010 Nov 16.
The formal synthesis of hemiterpene spirooxindole alkaloids elacomine (1) and isoelacomine (2) is described. Heck reaction of protected iodoanilines with 5,6-dihydro-2H-pyran-2-one or six-membered unsaturated lactams was investigated. The coupling product was readily converted to a carbamoyl chloride with an incorporated diene unit. The spiro(pyrrolidine-3,3'-oxindole) skeleton, which corresponds to the carbon skeleton of 1 and 2, was efficiently constructed from this intermediate by using a domino palladium-catalyzed Heck reaction and bismuth-catalyzed hydroamination. An isolated byproduct of the reaction could also be converted to the spirooxindole skeleton.
手性半萜螺环吲哚生物碱埃拉考明（1）和异埃拉考明（2）的全合成方法描述如下。用保护的碘苯胺与 5,6-二氢-2H-吡喃-2-酮或六元不饱和内酰胺进行 Heck 反应。该偶联产物很容易转化为带有内烯二炔单元的碳酰氯。该螺（吡咯烷-3,3'-吲哚）骨架与 1 和 2 的碳骨架相对应，可通过使用钯催化 Heck 反应和铋催化的氨化反应从该中间体有效地构建。反应的一种分离副产物也可转化为螺环吲哚骨架。
