Preface

This volume is dedicated to the memory of Prof. Dr. Gérard Descotes, a scientist, a gentleman, a friend, a colleague and a reference for carbohydrate chemists. He was a pioneer of the field and this book, with contributions of colleagues from all over the world, and of course, from many carbohydrate chemistry experts from France, clearly shows that we all wish to pay him a tribute not only for his many and innovative achievements, but also for his always remarkable behavior to colleagues and students, who have, indeed, become his friends!

Preceded by the Biography of Prof. Gérard Descotes, the first chapters of the book cover topics on carbohydrate chemistry, the major area of research of Gérard Descotes, starting with Chapter 1 by Peter Goekjian, and Descotes successor as leader of the Laboratoire Chimie Organique 2 at the Université Claude Bernard Lyon 1. This chapter is focused on applications of fluorous tag methodology assisting in solution-phase oligosaccharide synthesis, revealing fluorous tag-assisted synthesis as a very powerful tool for carbohydrate chemists. In chapter 2, authored by Zbigniew Pakulski, synthesis of natural and unnatural lupane conjugates and side reactions arising in these glycosylation reactions are discussed and the latest findings highlighted. The next chapter explores the chemical aspects and key challenges related to the syntheses of agrocinopines, which are bacterial carbohydrate phosphodiesters produced by pathogenic bacteria, authored by Yves Queneau and co-workers. In the present world seeking for sustainability, greener procedures are of course a pressing need. In Chapter 4 Srinivas Hotha and co-workers give a comprehensive overview of the greener methods in glycosylation, encouraging, indeed, further developments in this area of research. Chapter 5 is dedicated to Sonogashira reactions in carbohydrate chemistry, an area of research also developed witthin a Portuguese French cooperation between the Carbohydrate Chemistry Laboratory in Lisbon and the Institut de Chimie Organique et Analytique, Université d'Orléans, under leadership of Amélia Pilar Rauter and Patrick Rollin, respectively. In the next chapters, the latest findings on the development of chemical and biocatalysed strategies to transform unprotected glycosides are reviewed by Nadège Lubin-Germain and colleagues, and Sauthier and co-workers give an overview of anhydrohexitols, with diverse industrial applications as surfactants, plasticizers and solvents, focusing on strategies using both homogeneous and heterogeneous catalysis. In Chapter 8, Richard Daniellou and co-workers focus on another interesting topic covering the current procedures for the in situ generation of nucleotide-sugar substrates for glycosyltransferases to avoid the storage of activated glycosyl donors. Chapter 9 covers the enzymatic production of pentose-based molecules by Richard Plantier Royon and co-workers. The structures and properties of hexoses-, pentoses- and nucleosides-based organogelators are reviewed by Löic Lemiègre. Preparation of oligosaccharides on soluble support, the topic presented and discussed by Jean-Pierre Mallet and colleague in Chapter 11, is followed by the state of the art on glycomacrocycles built on disaccharides, which are chiral macrocyclic receptors with various applications, including in catalysis, authored by Slawomir Jarosz and co-worker. Glycomacrocycles are also the subject of the next chapter, where Juan Xie describes fluorescent and photocromic glycomacrocycles and their most recent synthetic strategies, properties and uses. Cyclopeptides are presented in Renaudet and colleague chapter, in which they revise their potency as inhibitors of surface binding receptors to prevent infection by virus and bacteria, opening the door of an anti-adhesive therapy in contrast to the treatment with antibiotics, as well as the approaches to fully synthetic vaccines derived from cyclopeptides. Chapter 15 covers the most recent findings on lectin FimH antagonists preventing biofilm formation on catheter surfaces, developed by Beat Ernst and his research group. This original article shows that p-cyanobiphenyl α-d-mannopyranoside is a potent preventive antagonist reducing type 1 pili-mediated biofilm mass by 50%, without affecting bacterial viability, and that co-administration of FimH antagonist and ciprofloxacin are very effective against biofilm-embedded bacteria. By potentiating antibiotics activity against uropathogenic Escherichia coli biofilm, these molecules are promising as prophylactic measures against catheter-associated urinary tract infections. The next chapter by Delannoy and collaborators is dedicated to O-acetylated gangliosides expression and biosynthesis, the most recent advances on the analytical methods and their importance as targets for cancer immunotherapy. The chapter, authored by Patrice Lerouge and co-workers, focuses on cell wall pectic rhamnogalacturonan II, resulting from plant adaptation to the land habitat from the marine ecosystem. It describes their distribution in plant kingdom, their structure, biosynthesis, localisation in the plant cell and biological functions. Francesco Nicotra and Laura Russo, together with their collaborators, have dedicated their chapter to diagnostic glycotools, where they first describe the specific glycans, known to date, in bacteria and virus pathological states, and in tumor and inflammation, and then the diagnostic tools functionalized with glycans, with antibodies and lectins covering lectin-based microarrays and lectin-based nanoparticles. The next chapter, by Xavier Coqueret and co-workers, is dedicated to the most recent advances in radiation chemistry on starch-based materials for the production of sustainable plastics. Etienne Fleury and collaborators focus their chapter on polyester thermosets from carbohydrates, covering cross-linking of polysaccharides by esterification of cotton cellulose, starch, and other natural materials as well as that of hydrogenated carbohydrates for production of biodegradable materials for biomedical devices. Finally, they report on eco-friendly, of simple preparation, biodegradable and biocompatible bio-sourced mixtures of sugar:carboxylic acid:water that are Brønsted Acidic Natural Low Transition Temperature Mixtures, and can be used to prepare polyester networks without catalysts at low temperature.

This volume, with its 20 chapters, really shows the uniqueness of carbohydrates for innovation in Chemistry and Biology. We sincerely hope that its content will stimulate researchers, particularly young researchers, for the carbohydrate area of research which holds, indeed, many secrets to be discovered towards a sustainable and healthier world.

We end this preface by thanking all the authors for their contributions dedicated to the memory of our dear friend Gérard Descotes, who is not among us in earth anymore, but is living in our heart and in our memory forever.

Amélia Pilar Rauter

Yves Queneau

Thisbe Lindhorst