醣化學為有機化學領域中重要的部分，不同的醣體會在生物表面上有不同的表現或是機制，深入了解醣在細胞表面扮演的角色有助於藥物發展以及疫苗開發。由於醣反應的特殊性以及結構的複雜性，這讓醣化學的發展受到阻礙。由於醣合成免不了繁雜的保護以及去保護過程因此本篇論文將討論具發展潛力的構建原件1,6-脫水-D-β-葡萄醣，1,6-脫水-D-β-葡萄醣上結構具有特殊的分子內自保護的鍵橋可以減少保護與去保護過程，加上不同於一般4C1醣體的1C4的構型，脫水醣上鍵橋對C3羥基造成立體結構使我們可以選擇性在C4上苄基和C2乙醯丙酸基保護。1,6-脫水-D-β-葡萄醣特殊的開環機制，提供了更多醣體在C1修飾的選擇，如接上疊氮後可以進行點擊化學反應等。最後修飾過後的1,6-脫水-D-β-葡萄醣能藉由立體構型選擇性與苷露醣予體進行 (1→3) 醣基化反應，而且C2、C4上不同的保護基也可以透過專一性去保護後得到的羥基進行 (1→2) 或 (1→4) 的選擇性醣基化反應，大幅增加醣基化反應路徑的多樣性。

Several glycans are prevalent at the surface of cells manifesting variety of functions making them to be targets of drug and vaccine development. To understand the mechanism of their functions, glycans of interest must be accessible in the required structural form and adequate quantity for biological assessments. To this end, chemical synthesis is one of the tools employed to access glycans. Due to structural complexity and diversity of glycans, their chemical synthesis needs a series of protection-deprotection procedures. Herein, we report the use of 1,6-anhydroglucose unit which consists of a special intramolecular self-protection bridge aimed at reducing the protectiondeprotection steps during glycan synthesis. Structurally, the 1,6-anhydro-D-β-glucoside has a 1C4 conformation which is different from the general 4C1 conformation of sugars. As the anhydro bridge creates a three-dimensional hindrance for the C3 OH group, the remaining two hydroxyl groups can be selectively modified with orthogonal protecting groups. In this case, while the C4 OH group was selectively benzylated, the C2 OH group was subjected to levulinoylaton. Then, the resulting 1,6-anhydro-D-β-glucoside can undergo (1→3) glycosylation reaction through the free C3 OH group with variety of glycoside donors to build disaccharides. Moreover, the orthogonal protecting groups at C2 and C4 can also be selectively removed to be used for (1→2) or (1→4) selective glycosylation which greatly increases the diversity of glycosylation reaction pathways.

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