Skip to main content
U.S. Department of Energy
Office of Scientific and Technical Information

Synthesis and characterization of iodobenzamide analogues: Potential D-2 dopamine receptor imaging agents

Journal Article · · Journal of Medicinal Chemistry; (USA)
DOI:https://doi.org/10.1021/jm00163a029· OSTI ID:7105468
; ; ;  [1]
  1. Univ. of Pennsylvania, Philadelphia (USA)

(S)-N-((1-Ethyl-2-pyrrolidinyl)methyl)-2-hydroxy-3-iodo-6- methoxybenzamide (({sup 123}I)IBZM) is a central nervous system (CNS) D-2 dopamine receptor imaging agent. In order to investigate the versatility of this parent structure in specific dopamine receptor localization and the potential for developing new dopamine receptor imaging agents, a series of new iodinated benzamides with fused ring systems, naphthalene (INAP) and benzofuran (IBF), was synthesized and radiolabeled, and the in vivo and in vitro biological properties were characterized. The best analogue of IBZM is IBF (21). The specific binding of ({sup 125}I)IBF (21) with rat striatal tissue preparation was found to be saturable and displayed a Kd of 0.106 {plus minus} 0.015 nM. Competition data of various receptor ligands for ({sup 125}I)IBF (21) binding show the following rank order of potency: spiperone greater than IBF (21) greater than IBZM greater than (+)-butaclamol greater than ({plus minus})-ADTN,6,7 greater than ketanserin greater than SCH-23390 much greater than propranolol. The in vivo biodistribution results confirm that ({sup 125}I)IBF (21) concentrated in the striatal area after iv injection into rats. The study demonstrates that ({sup 123}I)IBF (21) is a potential agent for imaging CNS D-2 dopamine receptors.

OSTI ID:
7105468
Journal Information:
Journal of Medicinal Chemistry; (USA), Journal Name: Journal of Medicinal Chemistry; (USA) Vol. 33:1; ISSN JMCMA; ISSN 0022-2623
Country of Publication:
United States
Language:
English