Screening solid-supported reagent

A solid-supported reagent, 9.67, was used to activate the monomer set Mi (60 carboxylic acids, step a. Fig. 9.28) added to the solid support as 6 mixtures of 10 representatives. The activated ester pools 9.68 were reacted with the monomer set M2 (amines and primary alcohols, step b. Fig. 9.28) and the library L17 was recovered, after filtration, as a set of 10-member pools with yields varying from 60 to 90% (mass recovery). Screening and deconvolution produced 9.69, an active compound of interest (Fig. 9.28, bottom). Its structure made it suitable for further optimization via focused library efforts, while its similarity to known bleachers also pointed toward a specific mechanism of action (118). No further efforts were reported by the authors. 

The compatibility of all these PEG-based resins with aqueous buffers allows their use for biochemical applications such as on-resin screening of chemical libraries and in the development of affinity chromatography [58-61]. All these families of PEG-based resins, except POEPS, are free of aromatic rings. This feature makes these solid supports highly suitable for a broad range of applications where such rings can react with reagents or/and jeopardize the solid-phase NMR control of the reactions [62]. 

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