Synthesis and characterisation of N-glycosyl amines from the reaction between 4,6- O-benzylidene- d-glucopyranose and substituted aromatic amines and also between 2-( o-aminophenyl)benzimidazole and pentoses or hexoses

• Published in: Carbohydrate research Vol. 334; no. 4; pp. 261 - 269
• Main Authors: Das, T.Mohan, Rao, Chebrolu P, Kolehmainen, Erkki
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier Ltd 07.09.2001
• Subjects: 2-( o-Aminophenyl)benzimidazole; 4,6- O-Benzylidene- d-glucopyranose; 4,6- O-Butylidene- d-glucopyranose; Amines - chemical synthesis; Amines - chemistry; Benzimidazoles - chemistry; Carbohydrate Sequence; Glucose - analogs & derivatives; Glucose - chemical synthesis; Glucose - chemistry; Glycosylation; Hexoses - chemistry; Hydrogen Bonding; Hydrogen-bonding interaction; Molecular Sequence Data; N-Glycosyl amines; Nuclear Magnetic Resonance, Biomolecular; Optical rotation; Pentoses - chemistry; Polycyclic Aromatic Hydrocarbons - chemistry; α and β anomers; 4,6- O-Butylidene- d-glucopyranose; Hydrogen-bonding interaction; N-Glycosyl amines; α and β anomers; Optical rotation; 4,6- O-Benzylidene- d-glucopyranose; 2-( o-Aminophenyl)benzimidazole
• ISSN: 0008-6215; 1873-426X
• DOI: 10.1016/S0008-6215(01)00202-6

Twelve N-glycosyl amines were synthesised using 4,6- O-benzylidene- d-glucopyranose and different substituted aromatic amines, including some diamines that resulted in bis-glycosyl amines. Another set of six N-glycosyl amines was synthesised using different hexoses and pentoses and 2-( o-aminophenyl)benzimidazole. All compounds were isolated as solid products and purified, their elemental compositions were established, and these were characterised by NMR ( 1H and 13C), UV–Vis, and FTIR spectroscopy, by FAB mass spectrometry (molecular-ion peaks gave molecular weights), and by their optical rotations. While the protected saccharide, 4,6- O-benzylidene- d-glucopyranose, exists as a mixture of β and α anomers in solution, the corresponding N-glycosyl amines were of only the β anomeric form as determined by NMR and FTIR spectroscopy. On the other hand, N-glycosyl amines synthesised from 2-( o-aminophenyl)benzimidazole prefer the α anomeric form, and in two cases a mixture of both the β and the α anomers were observed. The trends observed in the chemical shifts were compared among different products. Graphic