A protocol of introducing an electrophilic C1 fragment to a pterocarpan nucleus, followed by anionic coupling of a C6âC2 benzofuranoid precursor and late introduction of the final C6 fragment, permitted the syntheses of daljanelins B 3 and D 5. The feasibility of introducing the same electrophilic C1 fragment to C-2 of the pterocarpan moiety to obtain a precursor to daljanelin A 2 was also demonstrated.
将亲电子 C1 片段引入到
紫檀核中,然后进行 C6-C2
苯并呋喃类前体的阴离子偶联,最后引入最终的 C6 片段的方案,允许合成 daljanelins B 3 和 D 5。还证明了与
紫檀素部分的 C-2 具有相同的亲电子 C1 片段以获得 daljanelin A 2 的前体。