本論文敘述天然物valerenic acid之形式合成。我們以烯酮74為起始物，經過1,4-加成反應與碘化反應後，得到α-碘基環酮73，以自由基環化反應為關鍵步驟建立六,五-駢環的骨架部分。再以消去反應得到化合物71，先將化合物71還原成醇後做上TBS的保護得到化合物86。將化合物86進行氫化反應隨後去除TBS的保護得到醇85。最後利用官能基轉換得到已知的中間體43，完成了天然物valerenic acid的形式合成。

A formal synthesis of valerenic acid is described. The systhesis began with 1,4-addition of enone 74 followed by iodination to provide α-iodo ketone 73. The key step involved a radical cyclization of α-iodo ketone 73 to construct the [6,5]-bicyclic skeleton. Treatment of 82 with NaI and DBU resulted in elimination of tosylate followed by reduction of enone 71 and subsequent silyl protection of alcohol 84 gave 86. Hydrogenation of 86 followed by desilylation afforded alcohol 85. Conversion of 85 into the known intermedium ketone 43 completed the formal synthesis.

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