Synthesis of amylose acetates and amylose sulfates with high structural uniformity

Amylose triacetate (ATA) dissolved in DMSO was partially deacetylated by 1,6-hexamethylendiamine, 1,8-octamethylendiamine, 1,12-dodecylmethylendiamine and 1,2-cyclohexyldiamine (mixture of cis and trans isomers) at 80 degrees C. The reaction kinetics of the deacetylation were studied. Differences were found in the course of the reaction depending on the type of alkylene diamine (linear or cyclic). The isolated amylose acetates were dissolved in DMF and subsequently sulfated with sulfamic acid. In the course of the sulfation, the acetyl groups acted as protective groups and were completely cleaved after reaction. The amylose acetates and sulfates obtained were studied by 13C NMR spectroscopy and elemental analysis. It could be shown, that the deacetylation of ATA with the described alkylene diamines as well as the subsequent sulfation are highly regioselective. By proceeding this reaction scheme it is possible to synthesize 6-amyloseacetate, 2,6-di-amyloseacetate and 2-amylosesulfate with a high structural uniformity.