Carbohydrates (or glycans), one of the most complex and diversified components of all living organisms, were once thought to be more for structures than for function. Tremendous advances made during the last several decades have now made it clear that glycans play critical roles in virtually every aspect of biological processes. In addition, many glycans or glycoconjugates have proved to have promising diagnostic and therapeutic potential. Functional studies, practical applications, and even analysis of these extremely complex molecules rely on the access of structurally well-defined glycoforms.

The development of routine procedures for automated chemical synthesis of oligonucleotides and peptides has revolutionized modern biology. Unfortunately, no general methods are available for the preparation of complex carbohydrates. This is majorly due to the non-template driven biosynthesis, and the multiple connectivities and branching nature of glycans. Regardless of tremendous efforts and advances made over the past three decades in chemical synthesis, enzymatic assembly, and fermentations, synthetic glycans remain relegated to small quantities and specialized laboratories. Most problematically, the synthesis of even a single complex glycan can take a well-trained researcher months to years to accomplish. Transforming strategies and approaches that streamline the synthesis of complex glycans and are sufficiently robust to permit the preparation of large collections of various types of glycans (what we name “synthetic glycomes”) are in urgent demand for glycoscience to move ahead.

The book Synthetic Glycomes contains descriptions of the most recent advances in accessing complex glycans and glycoconjugates, including state-of-art approaches such as streamlined chemoenzymatic synthesis, reverse-synthesis (separation) and carbohydrate amplification. It also summarizes chemical methodologies for generating glycosidic bonds, useful synthetic enzymes, and commercial availabilities of glycans as well as glycan microarrays.

The book begins with an introduction to the glycomics and developed glyco-toolboxes (Chapter 1), as well as an overall summary of chemical methodologies for generating various glycosidic bonds (Chapter 2) and a summary of most synthetic-useful glycosyltransferases applied in the preparation of mammalian glycans (Chapter 3). The following eight chapters describe the most advanced strategies and technologies in streamlining the preparation of various mammalian glycans and glycoconjugates, including N-glycans (Chapters 4 and 5), O-mannosyl glycans (Chapter 6), glycopeptides and glycoproteins (Chapter 7), glycosaminoglycans (Chapters 8 and 9), glycosphingolipids (Chapter 10), and human milk oligosaccharides (Chapter 11). Chapter 12 describes the synthesis of marine polysaccharides/oligosaccharides and their derivatives. The next four chapters present some of the most advanced methodologies in preparing glycans other than traditional chemical and enzymatic synthesis, including bacterial fermentation (Chapter 13), solid-phase synthesis (Chapter 14), reverse synthesis (Chapter 15) and O-glycomics amplification (Chapter 16). The last section of the book contains chapters summarizing commercially available complex carbohydrates (Chapter 17) and glycan microarrays (Chapter 19), as well as the application of glycan microarrays in unmasking glycan functions (Chapter 18).

We would like to sincerely thank all authors who contributed to individual chapters. Without their significant efforts, the book would not have been possible. We also acknowledge all chapter reviewers, and all staff members of the Royal Society of Chemistry who helped us with the publication of this book.

Wanyi Guan

Lei Li

Peng George Wang