Our first aim was to develop a system where the target transporter is dynamically synthesised in situ in the lipid membrane from building blocks via azine metathesis. Azine metathesis is a reac7on similar to imine metathesis in which the subs7tuents of different azines are exchanged, resul7ng in a dynamic mixture of asymmetric and symmetric products at thermodynamic equilibrium. To control anion transport via azine metathesis, it was crucial to design both ac7ve and inac7ve transporters with an azine group. Therefore, we have started with building block T, consis7ng of a benzaldehyde with a bis(trifluoromethyl)phenylurea as the anion receptor unit (Fig. ). The laYer is a well-studied mo7f for the efficient binding and transport of anions such as Cl -. The aldehyde func7on can be readily transformed into an azine upon reac7on with hydrazine and another aldehyde, which serves as modulator for the transport ac7vity.