Figure 12 shows the structures of PN10630, Bis-MAL-Lysine-dPEG®4-acid (a. top), and PN10631, Bis-MAL-Lysine-dPEG®4-TFP ester (b. bottom). These two compounds consist of lysine functionalized with maleimide groups on both amines and conjugated to an acid-terminated dPEG®4 linker on the carboxyl group of lysine.
