SYNTHESIS AND CONFORMATIONAL ANALYSIS OF PSEUDOSUGAR ANALOGUES OF CHITOTRIOSE ^*

Abstract

EDC mediated coupling of the 4-O-succinoyl glycosyl azide 2 with glycosylamine 3 gave the protected glycosylazide 4. Hydrogenation of 4 afforded the glycosylamine 5. Chemoselective hydrolysis of the reducing end glycosylamine, followed by hydrogenation afforded N,N″-diacetylpseudochitotriose 7. Coupling of 5 with heterocyclic or with Cbz protected aliphatic amino acids yielded glycosyl amides 8–12. Deprotection of 11 and 12 afforded the N,N″-diacetylpseudochitotriosyl amides of β-alanine, 13, and l-arginine, 14. Molecular modelling calculations revealed that the pseudotrisaccharides exist in low energy extended conformations which show similar space filling as N,N′,N″-triacetylchitotriose.

^*Dedicated to Professor Dr. Joachim Thiem on the occasion of his 60th birthday.

Keywords:

• Chitotriose
• Glycosyl amides
• Molecular modelling
• Pseudooligosaccharides
• Sugar mimics
• Spacers
• Succinoyl amides

ACKNOWLEDGMENTS

This work was supported by EU grant no. BIO4-CT-960670. MGP acknowledges partial support by the Fonds der Chemischen Industrie. AG thanks the “Studienstiftung des Deutschen Volkes” for a PhD scholarship.

Notes

^*Dedicated to Professor Dr. Joachim Thiem on the occasion of his 60th birthday.