近年來研究發現，七圓環之azasugars (或稱為azepanes)，在結構上較五或六圓環之azasugars更具可變性(flexibility)，且更容易進入DNA的較小凹槽(DNA minor grove)，達到抑制效果。不具C2對稱之azepanes之合成在文獻上少有探討，於是我們以D-(-)-quinic acid為起始物，經過10個合成步驟，得到兩個新的7-Hydroxymethyl-3,4,5-trihydroxyazepanes標的物。並探討其立體化學對其抑制性的影響。
除此之外，最近有文獻報導，五七圓環bicyclic系統的azasugars (或稱為azaazulenes)，可能成為有潛力之醣水解酵素抑制劑。我們以trans-4-hydroxy-L-proline作為起始物，經過9個合成步驟，得到兩個新的polyhydroxyperhydroazaazulenes，並探討其抑制活性。 Azasugars are considered as glycosidase inhibitors and possess potential in treatment of diabetes, cancers, and AIDS.
Seven-membered azasugars were reported to be more conformationally flexible than the corresponding six- and five-membered counterparts, but little attention has been paid. We describe herein a new approach to the synthesis of diastereomeric 7-hydroxymethyl-3,4,5-trihydroxyazepanes in ten steps from D-(-)-quinic acid. We also compare the biological activities with C2-symmetrical tetrahydroxy -azepanes.
In addition, 5,7-heterocyclic ring system of azasugars (called azaazulenes) are also considered to be potential glycosidase inhibitors. We have established an expeditious synthesis of newpolyhydroxyperhydroazaazulenes from trans-4-hydroxy-L-proline.
