Prostaglandins (PGs) are recognized as a member of bioactive lipids. It is important to develop synthetic methods for further investigation of their biological activities. Among a variety of PGs, we decided to synthesize 15d-PGJ₂ (1) by employing an SmI₂-promoted radical cyclization as a key reaction. It was conceived that 3 would be assembled from bromolactone 4 utilizing the radical cyclization, however, 3 could not be obtained under the reaction conditions. On the other hand, the similar coupling reaction of bromoalkyne (R,E)-7a, the desired product syn-8 was given, via 3 for separation of diastereomers. The intermediate syn-8 was then transformed to Suh's intermediate (2) by several steps.

前列腺素（PGs）被认为是生物活性脂质的成员。开发进一步研究其生物学活性的合成方法很重要。在各种PG中，我们决定通过使用SmI ₂促进的自由基环化作为关键反应来合成15d-PGJ ₂（1）。认为可以使用自由基环化作用从溴内酯4组装3，但是在反应条件下不能获得3。在另一方面，bromoalkyne的类似偶联反应（[R ，ë） -图7a，所希望的产物顺式- 8通过3给出非对映异构体的分离。然后通过几个步骤将中间体syn - 8转化为Suh的中间体（2）。