Similarly to co-treatment with EDG, a 50% reduction in the cellular uptake of 1 was observed when a structurally and functionally different glucose transport inhibitor, phloretin, was used (Figure S14b). Moreover, given that D-glucose is the main substrate of GLUT1 and other glucose transporters, it should compete with and inhibit the protein-mediated uptake of the Glc-Pts. When probed, D-glucose, but not L-glucose, exhibited a weak but statistically significant (p < 0.01) inhibitory effect on the uptake of 1 (Figure 2b). The poor inhibitory effect (ca. 30% reduction in uptake) exerted by D-glucose can be attributed to the high binding affinity of 1 to glucose transporters, a phenomenon previously reported for other C6-glucose conjugates and GLUT1.[11b, 11c, 12] We also tested the effect of D-glucose on the cellular uptake of the aglycone 4 and found the uptake to be unaffected. Furthermore, in cytotoxicity assays carried out in the presence of EDG, the IC50 value of 1 increased 19-fold (Figure 2c). We note that EDG does not affect the ability of 1 to platinate DNA in vitro(Figure S16). In contrast to the results with 1, only a 6-fold increase in IC50 value was observed during cotreatment with the control aglycone 4 and EDG. The slight increase in IC50 value of 4 mirrors the observed decrease in cellular uptake of 4 in the presence of glucose transport inhibitors, which we attribute to energy depletion. In order probe Glc-Pt uptake through glucose transporters in an orthogonal manner, we capitalized on the fact that hypoxia causes stimulation of glucose transport and metabolism in cancer cells.[19] As shown in Figure S14a, cellular uptake of 1 increased by 50% when A549 cells were treated with the hypoxia-inducing agent cobalt(II) chloride.[20] No significant difference in the uptake of 4 was observed under similar conditions. In summary, the uptake assays support the hypothesis that glucose transporters, such as GLUT1, are at least partially involved in the cellular entry mechanism of 1.