“…In addition, the 6 -N-amide type of AL has been used for detecting endopeptidases, such as, α-chymotrypsin (Compound 123) [83], caspase 3/7 (Compound 124) [84], furin (Compound 125) [85], and fibroblast activation protein-α (Compound 126) [86]. In addition to enzymes, other targeted biomolecules include reactive oxygen species, such as hydrogen peroxide (Compound 127, 128) [87,88], hypochlorite (Compound 129, 130) [89,90], and peroxynitrite (Compound 131) [91], active sulfur molecular species, such as hydrogen sulfide (Compound 132-134) [92,93] and polysulfide (Compound 135) [94], and biothiols (Compound 136-139) [95][96][97] (Figure 7). Further, bioluminescence probes for ions, such as copper (Compound 140, 141) [98,99], palladium (Compound 142, 143) [100], iron (Compound 144) [101], and fluorine (Compound 145, 146) [102], have also been reported (Figure 8).…”