Catalytic Effects of Different Heparin Analogs on the Hydrolysis of Auramine O.

Glycosaminoglycans, such as heparin, are a class of biomaterials with a variety of important biological functions. They were found to catalyze the hydrolysis of 4,4'-(imidocarbonyl)-bis(N,N-dimethylaniline) monohydrochloride to 4,4'-bis(dimethy-lamino) benzophenone, but the catalytic mechanism of this interesting reaction is poorly understood, mainly due to the structural complexity of polysaccharides. In order to study such an unusual reaction, a pentasaccharide, fondaparinux, with defined chemical structure was chosen as a probe to investigate the hydrolytic characteristics, along with other heparin analogs. The hydrolytic reaction was catalyzed by fondaparinux, low-molecular-weight heparins, heparin and different desulfated heparins at various rates. The present results demonstrated that the length of polysaccharide chain, the N- or O-sulfo groups are critical to the hydrolysis of 4,4'-(imidocarbonyl)-bis(N,N-dimethy-laniline) monohydrochloride in addition to pH and ionic strength, which provides new insights into the catalytic phenomenon of polysaccharides.