倒地蜈蚣為台灣地區民間常使用之草藥，作為解熱和消炎劑，其學名為錫蘭七指蕨，其乾燥根莖已收錄在107年出版之「臺灣中藥典」第三版中。ugonin C與ugonin F在錫蘭七指蕨中分離得到的量非常 少，目前也沒有相關的全合成報導，本論文完成一有效之合成方法進行ugonin C與ugonin F的合成，同時探討抗氧化活性。
以phloroglucinol為起始物，經過6個步驟合成得到關鍵中間產物1-(6-(benzyloxy)-4-hydroxy-2,3,3-trimethyl-2,3-dihydrobenzofuran-5-yl)-2-methoxyethanone (18)，接著18再經過3個步驟生成ugonin C (1)，最後使用三溴化硼試劑，經去甲基化反應得到ugonin F (2)，抗氧化清除自由基活性分析，結果顯示ugonin F具有抗氧化活性，其活性程度相當於維生素E，而ugonin C則顯示沒有抗氧化活性，此結果表示在化合物2結構上C-3的羥基是對抗氧化活性是重要的部分。
Daodi-Ugon is a herbal medicine commonly used in Taiwan as an antipyretic and antiphlogistic agent. Its scientific name is Helminthostachys zeylanica. Its dry rhizoma has been included in the third edition of the Taiwan Herbal Pharmacopeia published in 2018. Ugonin C and Ugonin F were isolated as two minor components and there is currently no relevant synthetic report. In this thesis, an efficient synthetic method was accomplished to synthesize Ugonin C and Ugonin F. Antioxidant activity was also evaluated.
The key intermediate 1-(6-hydroxy-4-methoxy-2,3,3-trimethyl-2,3-dihydrobenzofuran-5-yl)ethanone (18) was prepared from starting phloroglucinol in six steps. Ugonin C (1) was obtained from 18 in three steps. Demethylation of ugonin C (1) with BBr3 yielded ugonin F (2). The antioxidative activity of synthesized compounds 1 and 2 using DPPH method was evaluated. Ugonin F (2) showed similar DPPH radical scavenging activity as those of -tocopherol (a positive control). However, ugonin C (1) showed no activity. The results indicated with the hydroxyl group in C-3 position of compound 2 is important for good antioxidative activity.
