本篇論文是以D-ribose作為起始物合成目標天然物(+)-Pericosine A-C。主要的反應有Wittig 反應、Swern 氧化。以[-(Alkoxycarbonyl)-vinyl]aluminum 作具有非鏡像選擇性的羰基加成反應得到中間產物8a和 8b。雖然此非鏡像混合物可以管柱層析法分離，我們也發展出改變反應條件 ( 添加過氯酸鋰 ) 可以得到不同的主產物，並探討了此非鏡像立體選擇性的原因。化合物8a經由甲基化反應( methylation )、環合置換 ( Ring-Closing Metathesis ) 反應合環，可得到天然物 (+)-Pericosine B。化合物8b使用相同的策略可以合成天然物 (+)-Pericosine C。而天然物(+)-Pericosine A可在8a經由環合置換反應後，參考Stevenson教授的合成方法而得。 Successfully synthesizing natural product (+)-Pericosine A-C was the aim. The main reactions are Wittig reaction and Swern oxidation. Diastereomeric intermediates 8a and 8b were acquired through [-(Alkoxycarbonyl)-vinyl]aluminum doing stereoselective nucleophilic reaction. Though diastereomers 8a and 8b could be separated by column chromatography, changing reaction condition by adding LiClO4 was found to result in different major product simultaneously, we did some researches on the cause leading to different stereoselectivity. Natural product (+)-Pericosine B was synthesized by compound 8a subjected to methylation, Ring-Closing Metathesis. On the other hand, natural product (+)-Pericosine C was obtained by using the same way as (+)-Pericosine B on compound 8b. Last but not least, (+)-Pericosine A was obtained by using compound 8a through Ring-Closing Metathesis directly referring to Prof. Stevenson’s method.
