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Published on: October 12, 2012
Catalytic Effects of Different Heparin Analogs on the Hydrolysis of Auramine O
Yunmian He1, Jianxin Li, Yijun Chen
1a Laboratory of Chemical Biology, China Pharmaceutical University, 24 Tongjia Street, Nanjing, Jiangsu 210009, P. R. China; Key Lab of Analytical Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, Jiangsu, 210093, P. R. China.
Abstract:
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.
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