Abstract
This thesis describes the development of a regioselective and one-pot methodology for the regioselective protection of the individual hydroxyl group of a monosaccharide in a single reaction flask, and the so formed building blocks are assembled into biologically important linkage region of proteoglycan, and related pentasaccharide via a one-pot approach. Chapter 1 introduces the cell surface glycoconjugates and the biosynthetic pathway of glycosaminoglycans. Chapter 2 present the regioselective one-pot protection of D-glucopyranoside, and chapter 3 reviews the recent advance in one-pot sequential glycosydation. Chapter 4 provides a brief introduction, and reviews the literature on the synthesis of linkage region tetrasaccharide. The specific aims and the retro-synthetic plan of the new preparative approach are illustrated in chapter 5. The new principle, condition, and proposed mechanisms for the one-pot protection of monosaccharides are described in chapter 6. The useful building blocks could be efficiently synthesized starting from a simple sugar. Chapter 7 exhibits the application to the one-pot synthesis of linkage region tetrasaccharide 132 and related pentasaccharide 138. The brief conclusion of our synthetic work is summarized in Chapter 8. Finally, Chapter 9 provides the detailed experimental section and physical data of the compounds synthesized herein.