不論是由天然物中萃取或是以合成方式得到之thiosugars都相當 稀少。重要的是，對於少數的七圓環thiosugars (thiepanes)之合成及生物活性近來也逐漸被重視。其中較令人感興趣的thiosugars，包括了:thiophenes,thiopyranes及thiepanes，其生物活性相較於azasugars是為弱的glycosidase 抑制劑。然而，自從發現salacinol及kotalanol為兩性離子結構後，thiosugars之合成也已被注意。目前，tetrahydro-thiepanes之合成主要是以D-mannitol 或 D-gluctiol為起始物。直到最近，我們已合成一系列polyhydroxylated azepanes。基於相同合成概念，我們以D-(-)-quinic acid為起始物，有效合成一系列新穎的七圓環之(3,4,6)-trihydrothiepane。於研究過程中，我們另外得到由thiepanes經重排之六圓環化合物-trihydrothiopyrans。 Naturally occurring or synthetic thiosugars are scarce. Especially, Here are few examples of synthesis and corresponding biological activities of seven-membered-ring thiosugars (thiepanes). The existing thio-sugars,including thiophenes, thiopyranes and thiepanes, are less potent in comparison to the homologous azasugars in terms of glycosidase inhibitors. However, their syntheses have attracted attention due to the discovery of salacinol and kotalanol that possess unique zwitterionic structures. The present syntheses of tetrahydro-thiepane mainly utilized etheir D-mannitol or D-gluctiol as starting materials. Recently we have synthesized a series of polyhydroxylated azepanes as potential glycosidase inhibitors. Based on the similar strategy, we report herein an expeditious synthesis of new seven-membered-ring thiosugars, (3,4,6)-trihydrothiepane, from D-(-)-quinic acid. During the course of studies, we also obtained the six-membered-ring trihydrothiopyrans that was derived from the ring contraction of their corresponding precursors, thiepanes.
