O,N,N'-trialkylisoureas as mild activating reagents for N-acylsulfonamide anchors.

[chemical reaction: see text]. Prior to detachment of compounds synthesized on sulfonamide based safety-catch linkers, the molecular anchor has to be activated. This is achieved by alkylation of the nitrogen atom of the N-acylsulfonamide using different established protocols. As an addition to the existing repertoire of activating reagents, we suggest the use of O,N,N'-trialkylisoureas. Besides the demonstration of the feasibility of these mild alkylating agents for this purpose, custom-tailored novel O,N,N'-trialkylisoureas prepared from electron-deficient alcohols are reported.