Abstract
Abnormal activity of various N-methyl-d-aspartate receptor (NMDAR) subtypes has been implicated in a wide variety of neurological disorders such as Alzheimer's disease, schizophrenia, and epilepsy. Imaging agents for PET and SPECT that target NMDARs in a subtype-selective fashion may enable better characterization of those disorders and enhance drug development. On the basis of a pyrazoline derivative that demonstrated neuroprotective effects in vivo, we synthesized a series of para-substituted analogues and measured their affinities to various NMDAR subtypes. Compounds 4a-c and 4e showed greater, nanomolar affinity for the GluN1/2A subtype versus GluN1/2B. Dicarbomethoxy (pro-drug) analogues of [124/125I]4d and [11C]4e (i.e., [124/125I]11d and [11C]11e) were generated and tested for NMDAR binding specificity in ex vivo autoradiography and brain biodistribution studies. Although NMDAR-specific binding could be demonstrated for [125I]11d and [11C]11e through autoradiography and biodistribution studies, imaging of neither [124I]11d nor [11C]11e could demonstrate brain penetration sufficient for detection by PET.
Original language | English |
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Pages (from-to) | 11110-11119 |
Number of pages | 10 |
Journal | Journal of Medicinal Chemistry |
Volume | 59 |
Issue number | 24 |
DOIs | |
State | Published - Dec 22 2016 |