Figure 2.

α,α-Diethyl glycine (DEG) amide probe design approach. (A) General construction scheme for CB₁R fluorescent probes based on DEG. (B) Selected drug-like CB₁R ligands⁴⁷⁻⁵² bearing amide bonds are useful as donors for CB₁R pharmacophoric units (blue) for the attachment to the DEG centerpiece. Amine fragments (black) were replaced with DEG. (C) Exemplified three-step probe exploration for CB₁R pyrrole-based fluorescent probes 28 and 29.