Part 1.

Index

Part 1.

pneumococcal diseases

Preface... 3

1.1. Streptococcus Pneumoniae: a worldwide pathogenic problem 3

1.2. Vaccines against pneumococcal diseases 3

1.3. Biological action of polysaccharide and conjugate vaccines 4

1.4. Aim of this research 6

1.5. Dendrimers: an introduction 7

1.6. Glycodendrimers 8

1.7. The use of glycodendrimers in biology: the multivalence effect 9

1.8. Synthesis of sugar-coated PAMAM dendrimers 11

Section 1. Preparation of CRM197 conjugate glycodendrimers loaded with SP19F

repeating units

15 1. Introduction... 17

1.1. Streptococcus Pneumoniae 19F 17

1.2. Literature syntheses of SP19F capsular polysaccharide fragments 17

2. Results and discussion... 22

2.1. Preparation of trisaccharide 38 22 2.2. SP19F glycodendrimer preparation 27 2.3. Coupling with CRM197 44 3. Experimental... 46 3.1. Preparation of trisaccharide 38 47 3.2. SP19F glycodendrimer preparation 60 3.3. Coupling with CRM197 76 4. References... 78

Section 2. Preparation of SP14 repeating units to be loaded on PAMAM dendrons 81 1. Introduction... 83

1.1. Streptococcus Pneumoniae 14 83

1.2. Literature syntheses of SP14 capsular polysaccharide fragments 84

1.3. A new synthetic approach to SP14 tetrasaccharide 85

1.3.1. Azidonitration 86

1.3.2. Cycloadditions with formation of pyrano-oxadiazines 87

1.3.3. Phosphoramidation 88

1.3.4. Sulfonamidoglycosylation 88

1.3.5. Transition metal-mediated amidation 89

1.3.6. Acetamidoglycosylation 90

1.4. The Heyns rearrangement revisited 91

2. Results and discussion... 94

2.1. Gin’s acetamidoglycosylation: lactosamine from lactal 94

2.2. Heinz rearrangement of lactulose 98

intermediates 99

2.4. Future developments 111

3. Experimental... 112

3.1. The Gin’s approach to lactosamine glycosides: general procedure for oxazoline

preparation from glycals 112

3.2. Monosaccharide approach to SP14 tetrasaccharide 118

4. References... 136

Part 2.

1. Introduction... 141

1.1. Natural killer cells 141

1.2. Natural killer cell receptors for carbohydrates 142

1.2.1. Type of sugar unit 142

1.2.2. Type of sugar linkage 143

1.3. Preparation of β-D-MacAc-(1
4)-D-Glc and β-D-TalNAc-(1
4)-D-Glc

disaccharides as agonists of NKR-P1 and CD69 receptors 144

1.4. Aim of this research 146

1.5. Iminosugars: past and present 146

1.6. Biological activity of 1-deoxynojirimycin (DNJ) and its derivatives 148

1.6.1. α-glucosidases inhibition 149

1.6.3. Gaucher’s disease 150

1.7. Synthesis of β-(1
4) azadisaccharides in literature 150

2. Results and discussion... 153

2.1. Preparation of GalNAc-DNJ precursor 24 154

2.2. Preparation of GlcNAc-DNJ precursor 30 154

2.3. Preparation of ManNAc-DNJ precursor 9 157

2.4. Regioselective acid hydrolysis of N-acetylhexosaminyl-β-(1
4)-DNJ precursors 157

2.5. Regioselective C-5 oxidation reaction 159

2.6. Stereoselective double reductive amination 162

2.7. Conversion of azido iminosugars 61 and 62 to acetamido ones and final

deprotections 166

2.8. Preparation of dendrimers loaded with potential NK activators 168

2.9. Evaluation of compounds 81 and 82 as activators of NKR-P1 and CD-69 receptors 179

3. Experimental... 181

3.1. Elaboration of disaccharide non-reducing end 181

3.2. Preparation of azasugar serie 13 191

3.3. Preparation of glycodendrimer loaded with NK-cell agonists 207

3.4. Preparation of soluble rNKR-P1A and hCD69 222

3.5. Plate binding and inhibition assays 223