1961 年 81 巻 7 号 p. 935-937
Lysine glucose ester, a kind of sugar ester of basic amino acid, was synthesized and its properties were examined. The synthesis started with 1, 2:3, 5-di-O-benzylidene-D-glucofuranose, N2, N6-bis(benzyloxycarbonyl)-L-lysine, and dicyclohexylcarbodiimide, which were reacted in molar ratio of 1:2:1 in pyridine, and the product, 6-O-[N2, N6-bis(benzyloxycarbonyl)-L-lysyl]-1, 2:3, 5-di-O-benzylidene-α-D-glucofuranose, was to be isolated and derived to the objective substance by hydrogenolysis. However, attempted liberation of the protective group from this product resulted in decomposition, and glucose and lysine alone were found in the reaction mixture. This seems to indicate that the objective lysine glucose ester is extremely labile in the aqueous solution and is rapidly hydrolysed into respective components after formation. A small amount of Ninhydrin-positive substance, other than lysine, was formed in this case and this was considered to be a peptide composed of lysine.
This behavior is similar to glycine glucose ester, the sugar esters of neutral amino acid described in the preceding paper, and it is therefore considered that the sugar esters of neutral and basic amino acids are such a labile substance that their isolation would be difficult.