己醛醣酸鹽水解酵素為一種醣水解酵素，其主要的功能為水解葡萄糖胺聚醣中硫酸乙醯肝素或皮膚素硫酸鹽末端的艾杜醣醛酸。此酵素的缺陷將造成第一型黏多醣症。但對研究己醛醣酸鹽水解酵素之文獻仍不完備。如利用化學合成方式取得己醛醣酸鹽水解酵素螢光受質，步驟繁瑣與產率不佳。以及在酵素抑制劑設計上的不明確。本論文的目的為改善現有人工合成、合成方法之不足處與探討酵素抑制劑的設計。
在己醛醣酸鹽水解酵素受質的製備，我們參考現有文獻，以3,6-丁內酯-D-葡萄喃醣為起始物。經由甲氧基開環與乙醯基化，再經由溴化反應以自由基反應將五號位置的立體組態翻轉，取得上保護的L-艾杜醣關鍵中間體。透過一號位置選擇性水解與醣基化反應，來取得己醛醣酸鹽水解酵素受質。
另一方面在己醛醣酸鹽水解酵素抑制劑的設計，由酵素受質與抑制劑的結構差異，讓我們在抑制劑的設計上，由抑制劑的構型上的差異、一號位置的位向以及一號位置的衍生化設計，來比較其分子結構與活性的關係。
己醛醣酸鹽水解酵素受質的合成目前可合成百毫克的受質，且實際應實際應用於本文中之生物活性測試上。在抑制劑的探討，以1C4的構型的艾杜醣酸也可當作抑制劑設計的骨架。藉由[3 + 2] cycloaddition來將此骨架在一號位置衍生化。所得到最具抑制效果化合物在100µM下具50% 抑制活性。此初步成果可提供未來化學分子設計之基礎。

Currently, the fluorescent substrate and inhibitors study of α-L-iduronidase were rarely mentioned in literatures. The purpose of this work is to improve the methods of synthesis of α-L-iduronidase fluorescent substrate and to design α-L-iduronidase inhibitors. In this work, inspired by known inhibitors and α-L-iduronidase substrates, we also synthesized new inhibitors and elucidated the conformation, configuration and C1 diversity of inhibitors to investigate the structure and activity relationship.

We have successfully and efficiently developed a convenient method to prepare about α-L-iduronidase fluorescent substrate in hundred milligram scalp, with which to study the enzyme and cell based inhibition assay. In terms of inhibitors, the L-iduronic acid with 1C4 conformation can be a potential scaffolds. By employing [3+2] cycoaddition to modify C-1 substituent to give inhibitors which showed 50% enzyme inhibition at 100 µM. This preliminary study provides the basis on designing α-L-iduronidase inhibitors in the future.

1. Beck, M., Therapy for lysosomal storage disorders. IUBMB Life. 2010, 62, 33-40.
2. Giugliani, R.; Federhen, A.; Silva, A.; Baldo, G.; Matte, U., Emerging treatment options for the mucopolysaccharidoses. Research and Reports in Endocrine Disorders. 2012, 53.
3. Bie, H.; Yin, J.; He, X.; Kermode, A. R.; Goddard-Borger, E. D.; Withers, S. G.; James, M. N., Insights into mucopolysaccharidosis I from the structure and action of alpha-L-iduronidase. Nat. Chem. Bio. 2013, 9, 739-745.
4. Terlato, N. J.; Cox, G. F.,Can mucopolysaccharidosis type I disease severity be
predicted based on a patient's genotype? A comprehensive review of the literature. Genetics in medicine : official journal of the American College of Medical Genetics. 2003, 5, 286-94.
5. Chandar, S. S.; Mahalingam, K., Mucopolysaccharidosis type I: Homology modeling and docking analysis of the lysosomal enzyme, human α-L-iduronidase. African Journal of Pharmacy and Pharmacology. 2012, 6, 2027-2038.
6. Valayannopoulos, V.; Wijburg, F. A., Therapy for the mucopolysaccharidoses. J.Rheumatol. 2011, 50, 49-59.
7. Gandhi, N. S.; Mancera, R. L., The structure of glycosaminoglycans and their interactions with proteins. Chem.Biol.Drug.Des. 2008, 72, 455-482.
8. Coutinho, M. F.; Lacerda, L.; Alves, S., Glycosaminoglycan storage disorders: a review. Biochem Res.Int. 2012, 2012, 1-16.
9. Nieman, C. E.; Wong, A. W.; He, S.; Hopwood, J. J.; Withers, S. G., Family 39 α-L-Iduronidases and β-D-Xylosidases React through Similar Glycosyl−Enzyme Intermediates:  Identification of the Human Iduronidase Nucleophile. Biochemistry 2003, 42, 8054-8065.
10. Clements, P. R.; Muller, V.; Hopwood, J. J., Human α-L-iduronidase. Eur. J. Biochem. 1985, 152, 29-34.
11. Baggett, N.; Samra, A. K.; Smithson, A., Synthesis of some aryl 2,3,4,6-tetra-O- acetyl-L-idopyranosides and of 4-methylcoumarin-7-yl α-l-idopyranosiduronic acid. Carbohydr. Res. 1983, 124, 63-74.
12. Lu, F. C.; Lico, L. S.; Hung, S. C., Synthesis of a fluorogenic substrate for α-L-iduronidase. ARKIVOC 2013, 2, 13-21.
13. Rempel, B. P., Synthesis and enzymatic evaluation of activated fluorosugars as inactivators of lysosomal enzymes. University of British Columbia. 2009.
14. Pabba, J.; Rempel, B. P.; Withers, S. G.; Vasella, A., Synthesis of Glycaro-,5-lactams and Tetrahydrotetrazolopyridine-5-carboxylates: Inhibitors of β-D-Glucuronidase and α-L-Iduronidase. Helv.Chim.Acta. 2006, 89, 635-666.
15. di Bello, I. C.; Dorling, P.; Fellows, L.; Winchester, B., Specific inhibition of human β-D-glucuronidase and α-L-iduronidase by a trihydroxy pipecolic acid of plant origin. FEBS Lett. 1984, 176, 61-64.
16. Fan, J.Q.; Ishii, S.; Asano, N.; Suzuki, Y., Accelerated transport and maturation of lysosomal α-galactosidase A in Fabry lymphoblasts by an enzyme inhibitor. Nat Med. 1999, 5, 112-115.
17. Hayes, J. A.; Eccles, K. S.; Lawrence, S. E.; Moynihan, H. A., Preparation and characterisation of solid state forms of paracetamol-O-glucuronide. Carbohydr. Res. 2012, 349, 108-112.
18. Yu, H. N.; Furukawa, J.-i.; Ikeda, T.; Wong, C.-H., Novel Efficient Routes to Heparin Monosaccharides and Disaccharides Achieved via Regio- and Stereoselective Glycosidation. Org. Lett. 2004, 6, 723-726.
19. Root, Y. Y.; Wagner, T. R.; Norris, P., Crystal structure of methyl 1,2,3,4-tetra -O-acetyl-β-D-glucopyranuronate. Carbohydr. Res. 2002, 337, 2343-2346.
20. Chiba, T.; Sinay, P., Application of a radical reaction to the synthesis of l-iduronic acid derivatives from D-glucuronic acid analogues. Carbohydr. Res. 1986, 151, 379-389.
21. Medaković, D., An efficient synthesis of methyl 1,2,3,4-tetra-O-acetyl -β-l- idopyranuronate. Carbohydr. Res. 1994, 253, 299-300.
22. Nudelman, A.; Herzig, J.; Gottlieb, H. E.; Keinan, E.; Sterling, J., Selective deacetylation of anomeric sugar acetates with tin alkoxides. Carbohydr. Res. 1987, 162, 145-152.
23. Györgydeák, Z.; Szilágyi, L.; Paulsen, H., Synthesis, Structure and Reactions of Glycosyl Azides. Journal of Carbohydrate Chemistry. 1993, 12, 139-163.
24. Czifrák, K.; Somsák, L., Radical-mediated bromination of carbohydrate derivatives: searching for alternative reaction conditions without carbon tetrachloride. Tetrahedron Lett. 2002, 43, 8849-8852.
25. Tsuzuki, Y.; Nguyen, T. K. N.; Garud, D. R.; Kuberan, B.; Koketsu, M., 4-Deoxy-4-fluoro-xyloside derivatives as inhibitors of glycosaminoglycan biosynthesis. Bioorg. Med. Chem. Lett. 2010, 20, 7269-7273.
26. Györgydeák, Z.; Thiem, J., Synthesis of methyl (D-glycopyranosyl azide) uronates. Carbohydr. Res. 1995, 268, 85-92.
27. Tosin, M.; Murphy, P. V., Synthesis of α-Glucuronic Acid and Amide Derivatives in the Presence of a Participating 2-Acyl Protecting Group. Org. Lett. 2002, 4, 3675-3678.
28. Wilkinson, B. L.; Bornaghi, L. F.; Poulsen, S.-A.; Houston, T. A., Synthetic utility of glycosyl triazoles in carbohydrate chemistry. Tetrahedron Lett.
2006, 62, 8115-8125.
29. Dedola, S.; Hughes, D. L.; Nepogodiev, S. A.; Rejzek, M.; Field, R. A., Synthesis of alpha- and beta-D-glucopyranosyl triazoles by CuAAC 'click chemistry': reactant tolerance, reaction rate, product structure and glucosidase inhibitory properties. Carbohydr. Res. 2010, 345, 1123-1134.