Mixed libraries, selectors

In contrast, there are fewer limitations from the chemical point of view. The preparation of large, well-defined, libraries that involve amino acid building blocks has been demonstrated many times. Carefully optimized reaction conditions for the preparation of other mixed libraries can also ensure that each desired compound is present in sufficient amount. However, the reaction rates of some individual selectors with the activated solid support may be lower than that of others. As a result, the more reactive selectors would occupy a majority of the sites within the beads. Since the most reactive selectors may not be the most selective, testing of a slightly larger number of specifically designed CSPs may be required to reduce the effect of falsenegative results. 

Fig. 3-16. Chromatograms of mixed libraries of 16 l (a) and 16 d (b) selectors using reciprocal stationary phase CSP 13. Conditions column 50 x 4.6 mm i.d. mobile phase gradient of 5-20 % 2-propanol in hexane flowrate, 1.2 mL min-1 UV detection at 254 nm. (Reprinted with permission from ref. [92]. Copyright 1999, American Chemical Society.)...

Modular Synthesis of a Mixed One-Bead - One-Selector Library... 

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