This title appears in the Scientific Report : 2015 

Synthesis and first evaluation of [18F]fluorocyano- and [18F]fluoronitro-quinoxalinedione as putative AMPA receptor antagonists
Olma, Sebastian (Corresponding author)
Ermert, Johannes / Sihver, Wiebke / Coenen, Heinrich Hubert
Nuklearchemie; INM-5
Medicinal chemistry, 11 (2015) 1, S. 13 - 20
Bussum [u.a.] Bentham Sc. Publ. 2015
10.2174/1573406410666140428151318
Journal Article
Neuroimaging
Neuroimaging
Please use the identifier: http://dx.doi.org/10.2174/1573406410666140428151318 in citations.
Abstract:Derivatives of quinoxalinedione (QX) were chosen as chemical lead for the development of new radioligands of the AMPA receptor, since there are several examples of QX-derivatives with high affinity. The radiosyntheses of the new compounds 6-[18F]fluoro-7-nitro-QX ([18F]FNQX) and 7-[18F]fluoro-6-cyano-QX ([18F]FCQX) with radiochemical yields of 8 ± 2 and 3 ± 2 %, respectively, as well as the evaluation of their binding properties to the AMPA-receptor were performed. A comparison of the Ki-values of the new QX-derivatives FCQX and FNQX with mono-substituted cyanoand nitro-QX shows negligibly small differences of affinity (within the range of 1.4 to 5 µM), but exhibits a tenfold lower affinity than derivatives with two electron withdrawing groups like the 7-cyano-6-nitro-compound CNQX and the 6,7- dinitro compound DNQX. Thus, with respect to the low affinity and a high non-specific binding with in vitro and ex vivo autoradiographic studies, the new compounds do not lend themselves for in vivo imaging.- See more at: http://www.eurekaselect.com/121871/article#sthash.JGpS3IVS.dpuf