Aldoses are structurally composed of a reactive aldehyde group and multiple hydroxy groups. Each specific sugar exhibits a defined stereochemistry of these alcoholic moieties, so they constitute a class of complex chiral aldehydes. Being constitutional isomers, the differentiation between sugars, especially in mixtures, is challenging. Previously, we have described a photometric kinetic assay to determine the open-chain content of aldoses utilizing the selective reaction with 2-aminobenzamidoxime (ABAO) [1]. Herein, we have taken further advantage of this aldehyde-selective reaction, using it for a qualitative aldose assay based on 19F-NMR, a highly sensitive and fast method. The influence of the position of the F‑label on the adduct formation rates was determined to ensure a fast reaction. Furthermore, derivatives of selected aldoses were prepared and the deviation of chemical shifts in 19F-NMR of the products were compared. While all four tested F-ABAO derivatives showed differences in shifts between the tested aldoses, one derivative was especially promising for the application in a qualitative sugar assay and the scope was expanded to all aldopentoses and aldohexoses for this derivative. An impressive influence of the stereochemistry up to 9 bonds apart from the fluorine atom on its chemical shift was observed, underlining the potential of F-labelled aminobenzamidoximes as probes for other types of aldehyde-mixtures within and beyond the sugar realm.