Reaction Steps
The precursors of the invention can be prepared by selectively hydrolysing the most reactive acyl-group of 1,2,3,4,6-pentaacetyl glucose (PAG), or 1,2,3,4-tetraacetylxylose (TAX), or 1,2,3,6-2',3',4',6'-octaacetyllactose (OAL) to produce 2,3,4,6-tetraacetylglucose, or 2,3,4-triacetylxylose, or 2,3,6-2',3',4',6'-heptaacetyllactose respectively, which may then be reacted with an acid chloride or anhydride of choice. In the same way other sugar deratives, such as 1,2,3,4,6-pentaacetylgalactose, 1,2,3,4-tetraacetyllyxose, 1,2,3,4-tetraacetylarabinose, and 1,2,3,6-2',3',4',6'-octa acetylmaltose, after hydrolysis of the most reactive anomeric acetyl group, will produce 2,3,4,6-tetraacetylglactose, 2,3,4-triacetyllyxose, 2,3,4-triacetylarabinose, and 2,3,6-2',3',4',6'-hepta acetylmaltose respectively, which can then be reacted with an acid chloride or anhydride of choice. Other examples of suitable precursors are those derived from acetylated cellibiose, mannose, fructose, melibiose and ribose.
