THE REACTION OF D-GLUCOSE WITH AMINOGUANIDINE

The reaction of D-glucose with aminoguanidine was examined at pH 7.0 a nd 37 degrees C (phosphate buffer). Under these conditions, the reacti on requires ca. 42 days for 50% of the sugar to react, as measured by the disappearance of D-glucose, and at 60 degrees C al the aminoguanid ine had reacted within 72 h. The initial product, a beta-D-glucopyrano syl aminoguanidine (1) was obtained in the crystalline state as the tr ifluoroacetate salt. Data collected on this compound suggests that, in solution, it is largely a glycosylamine in the beta pyranose form. Ac etylation gave a crystalline heptaacetate (2), which, in solution (as evidenced by NMR spectroscopy) exists in two different conformational forms. The crystal structure of the heptaacetate also includes two con formers. Both crystallographically independent molecules are in the no rmal beta pyranose form, with the acetylated guanyl residue occupying different spatial positions relative to the ring.