《Ring substituents on substituted benzamide ligands indirectly mediate interactions with position 7.39 of transmembrane helix 7 of the D4 dopamine receptor》 was written by Ericksen, Spencer S.; Cummings, David F.; Teer, Michael E.; Amdani, Shahnawaz; Schetz, John A.. Synthetic Route of C17H19N5 And the article was included in Journal of Pharmacology and Experimental Therapeutics on August 31 ,2012. The article conveys some information:
In an effort to delineate how specific mol. interactions of dopamine receptor ligand classes vary between D2-like dopamine receptor subtypes, a conserved threonine in transmembrane (TM) helix 7 (Thr7.39), implicated as a key ligand interaction site with biogenic amine G protein-coupled receptors, was substituted with alanine in D2 and D4 receptors. Interrogation of different ligand chemotypes for sensitivity to this substitution revealed enhanced affinity in the D4, but not the D2 receptor, specifically for substituted benzamides (SBAs) having polar 4- (para) and/or 5- (meta) benzamide ring substituents. D4-T7.39A was fully functional, and the mutation did not alter the sodium-mediated pos. and neg. allostery observed with SBAs and agonists, resp. With the exception of the non-SBA ligand (+)-butaclamol, which, in contrast to certain SBAs, had decreased affinity for the D4-T7.39A mutant, the interactions of numerous other ligands were unaffected by this mutation. SBAs were docked into D4 models in the same mode as observed for eticlopride in the D3 crystal structure. In this mode, interactions with TM5 and TM6 residues constrain the SBA ring position that produces distal steric crowding between pyrrolidinyl/diethylamine moieties and D4-Thr7.39. Ligand-residue interaction energy profiles suggest this crowding is mitigated by substitution with a smaller alanine. The profiles indicate sites that contribute to the SBA binding interaction and site-specific energy changes imparted by the D4-T7.39A mutation. Substantial interaction energy changes are observed at only a few positions, some of which are not conserved among the dopamine receptor subtypes and thus seem to account for this D4 subtype-specific structure-activity relationship. In the experiment, the researchers used many compounds, for example, Abt-724(cas: 70006-24-5Synthetic Route of C17H19N5)
Abt-724(cas: 70006-24-5) belongs to piperazines. Two common salts in the form of which piperazine is usually prepared for pharmaceutical or veterinary purposes are the citrate, 3C4H10N2.2C6H8O7 (i.e. containing 3 molecules of piperazine to 2 molecules of citric acid), and the adipate, C4H10N2.C6H10O4 (containing 1 molecule each of piperazine and adipic acid).Synthetic Route of C17H19N5
Referemce:
Piperazine – Wikipedia,
Piperazines – an overview | ScienceDirect Topics