COORDINATION ABILITY OF SELECTED AMINO-SUGARS WITH CU2+ IONS IN SOLUTION

Complex formation between Cu(II) and the amino sugars methyl-beta-L-da unosaminide (MeDauN), 6-amino-6-deoxy-D-glucose (Glc6N), 3-dimethylami no-3,4,6-trideoxy-D-xyloheksose (desosamine DSA), and methyl-3-amino-3 -deoxy-alpha-D-mannopyranose (MeMan3N) was studied in aqueous solution by potentiometric and spectroscopic (EPR, electron absorption, and CD ) techniques. The results show that Glc6N and DSA ligands, lacking the cis-oriented couples of [NH2, OH] donors, give rise only to dimeric c omplexes. The other two ligands, although both forming mononuclear spe cies, exhibit different coordination abilities, depending on the assis tance of donors able to yield axial interaction with the metal ion.