Synthesis and Cerebral Uptake of 1-(1-[ 11 C]Methyl-1 H -pyrrol-2-yl)-2-phenyl-2-(1-pyrrolidinyl)ethanone, a Novel Tracer for Positron Emission Tomography Studies of Monoamine Oxidase Type A

PET Centre, Aarhus University Hospital, Nørrebrogade 44, Arhus C, Denmark.
Journal of Medicinal Chemistry (Impact Factor: 5.48). 04/2008; 51(6):1617-22. DOI: 10.1021/jm701378e
Source: PubMed

ABSTRACT ( R)-(-)- and ( S)-(+)-1-(1-[ (11)C]methyl-1 H-pyrrol-2-yl)-2-phenyl-2-(1-pyrrolidinyl)ethanone 4 and 5 were synthesized, and their properties as tracers for positron emission tomography (PET) studies of monoamine oxidase type A (MAO-A) in the brain of living pigs were tested. Parametric maps of the distribution volume ( V d) 4 in pig brain were qualitatively similar to those obtained with [ (11)C]harmine, with prominent binding in the ventral forebrain and mesencephalon. Its binding was highly vulnerable to MAO blockade, suggesting a binding potential as high as 2 for MAO-A sites. The slow plasma metabolism of 4 and 5 may present advantages over [ (11)C]harmine for routine PET studies of MAO-A.

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Available from: Roberto Di Santo, Apr 18, 2014
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    • "[ 11 C]-harmine showed favorable kinetics and showed sensitivity to pretreatment with selective MAO-A inhibitors. (R-(À) and (S)-( + )- 1-1[11C]methyl-1H-pyrrol-2-yl)-2-phenyl-2-(1-pyrro- lidinyl)ethanone were also synthetized and characterized in vivo (Jensen et al, 2008). They presented two obvious advantages over harmine: a simple radiosynthesis with high yield and a slower plasma metabolism. "
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