pubmed:abstractText |
A new series of heteroaromatic GBR 12935 [1-[2-(diphenylmethoxy)ethyl]-4-(3-phenylpropyl)-piperazine] (I) and GBR 12909 [1-[2-[bis(4-fluorophenyl)methoxy]ethyl]-4-(3-phenylpropyl)piperazine] (2) analogs was synthesized and evaluated as dopamine transporter (DAT) ligands. Analogs 5-16, in which the benzene ring in the phenylpropyl side chain of the GBR molecule had been replaced with a thiophene, furan, or pyridine ring, exhibited high affinity and selectivity for the DAT vs serotonin transporter (SERT) and stimulated locomotor activity in rats in a manner similar to the parent compound 2. In cocaine and food self-administration studies in rhesus monkeys, both thiophene-containing (6 and 8) and pyridine-containing (14 and 16) derivatives displayed potency comparable to 2 in decreasing the cocaine-maintained responding at the doses tested (0.8, 1.7, and 3 mg/kg). However, these compounds did not produce the degree of separation between food- and cocaine-maintained responding that was seen with 2. Among the bicyclic fused-ring congeners 17-38, the indole-containing analog of 2, 22, showed the greatest affinity for binding to the DAT, with IC50 = 0.7 nM, whereas the corresponding indole-containing derivative of 1, 21, displayed the highest selectivity (over 600-fold) at this site vs the SERT site.
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pubmed:affiliation |
Laboratory of Medicinal Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland 20892, USA.
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