We next evaluated the cellular activities of CRBN/VHL-targeting FerroTACs. Using immunoblot analysis, we quantified VHL and CRBN protein levels in HEK293 cells following treatment with 0.1 µM and 1 µM of the compounds for 6 and 24 hours, with CM11, 14a and cisAS1, serving as positive and negative controls, respectively (Figure ). Interestingly, significant CRBN degradation was observed with AS4 and AS5 at 1 µM, while no substantial VHL degradation was detected, consistent with the reported profile of 14a. Consequently, AS4 and AS5 were selected for dose-dependent studies (Figure ), revealing DC50 values of approx. 158 nM for AS4 and 527 nM for AS5, compared to 14a's 50 of 200 nM . For BET proteins, the degradation data from AS6 and AS7 in the initial screening via Western blot (Figure ) was confirmed by lytic and live-cell kinetic degradation assays in HEK293 cell lines expressing HiBiT-tagged BRD2, BRD3, and BRD4. AS7 was found to be inactive in the initial screening at 6 hours and 24 hours (Figure ) and was excluded from further evaluation. We investigated AS6 in HiBiT-tagged cells with varying concentrations, alongside the positive control MZ1 and the negative control cisMZ1. AS6 induced the degradation of BRD2, BRD3, and BRD4 with DC50 values of approximately 181 nM, 59 nM and 44 nM, respectively, compared to MZ1, which showed DC50 values of 105 nM, 166 nM, and 46 nM (Figure ). Kinetic studies (Figure ) further demonstrated rapid and complete degradation of these targets with comparable t1/2 to the reference compound (Figure , table ).