Line charts showing dose-dependent inhibition of SS cell sickling from experiments. Briefly, hematocrit-normalized SS RBCs were incubated with 0, 1, 2, or 5 mM test compounds under 4% oxygen gas at 37 °C for 2 h, after which aliquot samples were obtained, fixed, and analyzed for degrees of sickling. The superior effects of VZHE006 (a) and 5-PMFC (c) over 5-HMF (dotted lines) are clearly demonstrated at 2 mM concentrations. Improved properties of VZHE011 and VZHE015 are also shown (b). Sickling inhibition, reported as mean values from three replicates, was calculated by normalizing to untreated control samples, as detailed in Table 2.