Ganglio-series gangliosides

A. Hasegawa, T. Nagahama, and M. Kiso, A facile, systematic synthesis of ganglio-series gangliosides Total synthesis of gangliosides GM, and GDla, Carbohydr. Res. 235 C 3 (1992). 

Synthesis of Polysialo Ganglio-Series Gangliosides 313 12.3.1 Retrosynthetic Analysis of GQlb... 

GD2 pentasaccharide acceptor 14 was selected as the key compound to achieve the systematic synthesis of polysialo ganglio-series gangliosides (Scheme 7). Glyco-sylation of GA2 acceptor 12 with a-sialyl-(2— 8)-sialic acid donor 13 in the presence of NIS-TfOH in acetonitrile at -25 °C, afforded the desired pentasaccharide in 50% and no P-isomer was isolated. De-O-isopropylidenation of the pentasaccharide with aqueous 80% acetic acid afforded the acceptor 14 in 91% yield. It is noteworthy that the key intermediate 14 was prepared by one step, de-O-isopropylidenation, after the construction of GD2 pentasaccharide, in contrast to the synthesis of GDI a. 

In this chapter, the methodology to synthesize a series of a-series as well as b-series ganglio-series gangliosides is described. By combining the two procedures, all of... 

Kotani, M., Ozawa, H., Kawashima, I., Ando, S., and Tai, T, 1992, Generation of one set of monoclonal antibodies specific for a-pathway ganglio-series gangliosides, Biochim. Biophys. Acta 1117 97-103. 

Because high levels of ganglio-series gangliosides are found in neural tissues, ganglioside research has traditionally been linked with neurochemistry. However, aside from their role as cell type-specific antigens, the real function of gangliosides remains obscure (see Chapter 6). In comparison with studies of functional proteins, enzymes, antibodies, adhesion molecules, receptors, etc.,... 

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