93801-18-4Relevant articles and documents
Design of a True Bivalent Ligand with Picomolar Binding Affinity for a G Protein-Coupled Receptor Homodimer
Pulido, Daniel,Casadó-Anguera, Verònica,Pérez-Benito, Laura,Moreno, Estefanía,Cordomí, Arnau,López, Laura,Cortés, Antoni,Ferré, Sergi,Pardo, Leonardo,Casadó, Vicent,Royo, Miriam
, p. 9335 - 9346 (2018/10/24)
Bivalent ligands have emerged as chemical tools to study G protein-coupled receptor dimers. Using a combination of computational, chemical, and biochemical tools, here we describe the design of bivalent ligand 13 with high affinity (KDB1 = 21 pM) for the dopamine D2 receptor (D2R) homodimer. Bivalent ligand 13 enhances the binding affinity relative to monovalent compound 15 by 37-fold, indicating simultaneous binding at both protomers. Using synthetic peptides with amino acid sequences of transmembrane (TM) domains of D2R, we provide evidence that TM6 forms the interface of the homodimer. Notably, the disturber peptide TAT-TM6 decreased the binding of bivalent ligand 13 by 52-fold and had no effect on monovalent compound 15, confirming the D2R homodimer through TM6 ex vivo. In conclusion, by using a versatile multivalent chemical platform, we have developed a precise strategy to generate a true bivalent ligand that simultaneously targets both orthosteric sites of the D2R homodimer.
Fluorescent Probes for Dopamine Receptors: Synthesis and Characterization of Fluorescein and 7-Nitrobenz-2-oxa-1,3-diazol-4-yl Conjugates of D-1 and D-2 Receptor Ligands
Bakthavachalam, Venkatesalu,Baindur, Nandkishore,Madras, Bertha K.,Neumeyer, John L.
, p. 3235 - 3241 (2007/10/02)
Fluorescent probes have been designed and developed for dopamine D-1 and D-2 receptors.Fluorescein and/or NBD (7-nitrobenz-2-oxa-1,3-diazol-4-yl)derivatives of PPHT (D-2 agonist), spiperone (D-2 antagonist), SKF 38393 (D-1 agonist), and SKF 83566 (D-1 antagonist) were synthesized via their amino-functionalized analogues and all ligands were pharmacologically evaluated by measuring their ability to displace SCH 23390 and 3H)spiperone from D-1 and D-2 receptor sites in caudate putamen of monkeys (Macaca fascicularis).The fluorescein derivatives of PPHT andSKF 83566 and the NBD derivatives of spiperone and SKF 83566 retained the high affinity and selectivity of parent ligands.The NBD derivatives of PPHT showed higher D-2 receptor affinity and selectivity than their parent ligands.The enantiomers of the fluorescent derivatives of PPHT were also synthesized and were found to exhibit stereoselectivity in binding to the D-2 receptor, with the S enantiomers having a considerably higher affinity than their R analogues.In contrast to these results, the fluorescein derivative of SKF 38393 showed only a low affinity for the D-1 receptor.These fluorescein- and NBD-coupled D-1 and D-2 receptor ligands have considerable significance as potential probes in the study of distribution of the receptors at the cellular/subcellular level and of their mobility in membranes in normal/diseased states by use of fluorescence microscopic and fluorescence photobleaching recovery techniques, respectively.The development of these novel fluorescent probes should also provide new leads for the design and synthesis of additional fluorescent ligands with better fluorescent properties and/or higher affinity/selectivity for the DA receptors.
