This title appears in the Scientific Report : 2004 

First no-carrier-added radioselenation of an adenosine-A1 receptor ligand
Blum, T.
Ermert, J. / Wutz, W. / Bier, D. / Coenen, H. H.
Institut für Nuklearchemie; INC
Journal of Labelled Compounds and Radiopharmaceuticals Journal of labelled compounds and radiopharmaceuticals, 47 (2004) S. 415 - 427
New York, NY [u.a.] Wiley 2004
415 - 427
Journal Article
Journal of Labelled Compounds and Radiopharmaceuticals 47
Please use the identifier: in citations.
The precursor synthesis and the no-carrier-added (n.c.a.) radiosynthesis of the adenosine-A(1) receptor ligand 5'-(methyl[Se-75]seleno)-N-6-cyclopentyladenosine ([Se-75]1) are described in this report. A method was developed starting from elemental n.c.a. selenium-75, followed by a three-step polymer-supported radioselenation and deprotection which gave the radioligand with a radiochemical yield of 30%, a radiochemical purity of > 99% and a specific radioactivity of > 300 GBq/mmol (8 Ci/ mmol). Preparation time was 40 min. The nonradioactive compound 5'-(methylseleno)-N-6-cyclopentyladenosine (1) was, pharmacologically evaluated in vitro and showed high affinity and selectivity for the adenosine-A(1) receptor. These preliminary results suggest that this compound could be a useful radioligand for the noninvasive imaging of the brain adenosine-A(1) receptors using positron emission tomography (PET) when labelled with the positron emitter selenium-73 (half-life: 7.1 h). Copyright (C) 2004 John Wiley Sons, Ltd.