Hexose diphosphate hydrolysis

Hexose Diphosphate.— Fructofuranose-1 6-diphosphoric acid, (Harden-Young ester), CsHjo04(HgP04)2, is formed in the first stage of the fermentation of glucose, mannose or fructose by yeast. The phosphate on hydrolysis by boiling yields fructose, and its formation is an example of the interconvertibility of the three monosaccharides. It is also an early product in the conversion of glycogen into lactic acid, in muscle. 

This ester was first prepared 209) by partial hydrolysis of D-fructose diphosphate and later isolated by Robison 210) from the hexose monophosphate fraction obtained by yeast juice fermentation. 

Fructose Monophosphate.— This ester has been obtained by Neuberg from the 1 6-diphosphate by partial hydrolysis. Unlike the diphosphate, it is fermented by yeast. Neuberg s ester is one of the two hexose phosphates found in muscle. 

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