以五元環為基底的亞胺醣分子已經被我們實驗室廣泛的合成，但是經由五元環亞胺醣分子製備六元環多羥基的亞胺醣分子還沒有被廣泛的討論，因此我們找出一個有系統的開環方法，從五元環亞胺醣分子去製備六元環多羥基的亞胺醣分子，並且有系統的探討當中的影響因素，像是氮上取代基的影響，反應當中溫度跟溶劑的影響還有反應物上各種不同立體異構中心的影響。探討完有利的開環條件之後，我們將利用這個方法去製備更具有多樣性的六元環亞胺醣分子，並且去找出有潛力的艾杜糖醛酸脢抑制劑。

Iminosugars, particularly polyhydroxylated pyrrolidines and piperidines, are biologically interesting alkaloids and some alkaloids have shown therapeutic applications in the treatment of diabetes and lysosomal storage disease.
From the structural point of view, these molecules contain polyhydroxylated groups and multi-stereogenic centers, causing the difficulty in the preparation and modification. Comprehensive synthesis of pyrrolidine-based iminosugars has been reported in our lab. However, preparation of polyhydroxylated piperidines from pyrroldines via ring expansion has not been extensively explored. In this work, we would like to systematically investigate various factors during the aziridinium ring expansion from a polyhydroxylated pyrrolidine into a polyhydroxylated piperidine.
With these valuable ring expansion conditions in hand, we applied this approach to prepare diversely functionalized piperidines, and also used them for inhibition study toward alpha-L-iduronidase.

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