Tetrel-Centered Exchange Cascades to Decouple Inhibition and Induction of Thiol-Mediated Uptake: Introducing Cell-Penetrating Thiolactones, Focus on Reversible Michael Acceptor Dimers

This study adds thiolactones to the collection of cascade exchangers (CAXs) and reports with dynamic covalent Michael acceptor dimers the first CAXs that rather inhibit than enable thiol-mediated uptake. The superior performance of dimers compared to monomeric Michael acceptors as inhibitors might suggest that top inhibitors move along thiol/ate arrays without losing covalent contact, while cell penetrators exchange along disulfide arrays. This decoupling of inhibition and induction of thiol-mediated uptake is important because the latter is promising for drug delivery, while the former possibly helps to reveal targets associated with antiviral, antithrombotic and antitumor activity, leading to drug discovery. These results are consistent with the working model of thiol-mediated uptake as a general complex network in charge of bringing matter into cells, and thus support its validity.