The nitration of fructose by means of nitrogen pentoxide-sodium fluoride, yielded a mixture consisting of a crystalline product (I) and sirupy monomeric nitrated products. The isolation, characterization, and elucidation of the structure of I as l,4,6-tri-0-nitro-2,3-anhydrofructofuranose is described.Unlike the nitration of aldoses, which proved to undergo a smooth O-nitration (esterification) reaction by a variety of reagents,1 the nitration of ketoses attracted considerably less attention. Back in 1898, Will and Lenze2 studied the nitration of both fructose and sorbose by means of the powerful nitrating agent, nitric acid-sulfuric acid mixture. However, they could not obtain the expected fully nitrated products. In both cases they were able only to isolate products which according to analyses were formulated as the respective anhydroketosetrinitrates. This nitration of fructose has lately been reinvestigated by Schwager and Leibowitz3 who showed that the crude reaction product consisted exclusively of a mixture of dimeric fructose nitrates. Among the several products isolated, at least two were identified as hexanitrates of the known difructose-dianhydrides.