Figure 3.

Analysis of the efficiency of macrocyclization of 64 PICCO scaffolds created by parallel solid-phase synthesis. A) Structures of the building blocks employed (box) and the protocol employed for macrocylization. Diamine K was always employed following acid B, while amine L was always used following all of the other acids. This is because acylation of N-alkylated alanines is difficult.^[19] Cy5-azide dye was attached to alkyne handle of the linker, the thiol protection was removed and the beads were stained with mBBr eight hours later. Bead fluorescence was then analyzed using a flow cytometer. B) Summary of ring-closure status of 64 scaffolds from FACS & LCMS analysis. Cells in yellow indicate scaffolds that had between 5–40% linear material after 8 hours while red indicates scaffolds that had more than 40% linear material present. The rest of the scaffolds did not show any detectable linear material. C) FACS plots for the control molecules 2 and 3 (see Figure 1). D) FACS plots for selected scaffolds that showed a high degree of cyclization after eight hours. E) Selected scaffolds that showed incomplete cyclization after eight hours (top row of FACS plots) but completed macrocyclization by 16 h (bottom row of FACS plots).