Abstract
Fructose-1, 2-cyclic phosphates(F-1, 2-Ps) and fructose-2-phosphates(F-2-Ps) were synthesized according to the method of Pontis and Fischer and their properties toward acid hydrolysis were examined in detail. Fructopyranose-2-phosphate(Ep-2-P) showed exactly the same properties as those reported by Pontis and Fischer. On the other hand, a part of fructofuranose-2-phosphate(Ff-2-P) was converted into the acid-stable form during acid treatment and this substance increased progressively when the sample was stored at -20°C for a longer time. This acid-stable form resembled in its properties to the fructose phosphate obtained from UDP(2)-fructose by the action of nucleotide pyrophosphatase.
When treated with acid at room temperature, fructopyranose-1, 2-cyclic phosphate(Fp-1, 2-P) was almost completely hydrolyzed into fructose and inorganic phosphate, whereas only about 50% of fructofuranose-1, 2-cyclic phosphate(Ff-1, 2-P) was hydrolyzed into fructose and inorganic phosphate and the remainder was hydrolyzed into fructose-1-phosphate(F-1-P). On the other hand, when treated with acid at 100°C, 90% of both cyclic phosphates were hydrolyzed into F-1-P, and fructose and inorganic phosphate were formed only slightly.
