Fluorine-18 labeled benzamides for studying the dopamine D2 receptor with positron emission tomography
摘要:
Two series of (N-benzylpiperidin-4-yl)- and (9-azabicyclo[3.3.1]nonan-3beta-yl)benzamides were prepared, and in vitro binding assays were used to measure the affinity of these compounds for dopamine D2, dopamine D3, serotonin 5-HT2, and alpha2-adrenergic receptors. The results of these studies indicated compounds 23, 26b, and 34 have the selectivity needed for in vivo studies of the D2 (and possibly D3) receptors. F-18-Labeled analogues of 23, 26b and 34 were prepared by N-alkylation of the corresponding desbenzyl precursors with [F-18]-4-fluorobenzyl iodide. Preliminary in vivo studies demonstrated that [F-18]-23 and [F-18]-26b are suitable candidates for further evaluation in positron emission tomography imaging studies. The slow rate of washout of [F-18]-34 from nondopaminergic regions and its comparatively high lipophilicity indicates that this compound may not be suitable for imaging studies because of a high level of nonspecific binding.
Compounds of formula (I): ##STR1## wherein X is methoxy or ethoxy, Y is amino or C.sub.1-6 alkanoylamino, Z is hydrogen, chloro or bromo and R.sub.1 is methyl, chloro or fluoro, have anti-psychotic activity, and are useful in the treatment of CNS disorders.
9-Azabicyclo(3.3.1) nonane intermediates for compounds useful in the
申请人:Beecham Group p.l.c.
公开号:US04560757A1
公开(公告)日:1985-12-24
Compounds of formula (I): ##STR1## wherein X is methoxy or ethoxy, Y is amino or C.sub.1-6 alkanoylamino, Z is hydrogen, chloro or bromo and R.sub.1 is methyl, chloro or fluoro, have anti-psychotic activity, and are useful in the treatment of CNS disorders. Intermediates for the above compounds are also disclosed.