Synthesis and In Vitro Evaluation of Novel Nortropane Derivatives as Potential Radiotracers for Muscarinic M2 Receptors
Figure 2
Competition curves of 6β-acetoxynortropane (5a, for M2 in two separate experiments 88.1 nM and 71.6 nM, resp.) and the 6β-4′-iodobenzyl ether (5b, for M2 3.0 μM) and 6β-4′-iodobenzoate ester (5c, for M2 6.8 μM) of 6β-nortropinol, 3β-phenyl-6β-acetoxynortropane (10a, for M2 > 1 μM), and 3α-hydroxy-3β-phenyl-6β-acetoxynortropane(10b, for M2 > 1 μM) to the binding of [3H]NMS to the muscarinic receptor subtypes M1–M3. In the curves of (a, c, e) (derivatives 5a, 5b, 5c), data are expressed as means ± SEM from 3 samples in a range of M to M of competitor concentrations. In the curves of (b, d, f) (derivatives 5a, 10a, 10b), data are expressed as means ± SEM from 4 samples in a range of M to M of competitor concentrations. Atropine curves are also displayed as a reference.
