(–)-2β-Carbomethoxy-3β-(4-ethylphenyl)tropane (RTI-83) is a phenyltropane derivative which represents a rare example of an SDRI or serotonin-dopamine reuptake inhibitor, a drug which inhibits the reuptake of the neurotransmittersserotonin and dopamine, while having little or no effect on the reuptake of the related neurotransmitter noradrenaline. With a binding affinity (Ki) of 55 nM at DAT and 28.4 nM at SERT but only 4030 nM at NET, RTI-83 has reasonable selectivity for DAT/SERT over NET, but further research has shown that by extending the ethyl chain even better selectivity can be achieved, with the 4′-(cis-propenyl) analogue having Ki values of 15 nM at DAT and 7.1 nM at SERT, vs 28,000 nM at NET.
cis-propenyl analogue (RTI-11w)
Such drugs are speculated to be useful as potential antidepressants, but few examples have been reported in the literature as yet. However while RTI-83 has been used for binding studies to model the monoamine transporter proteins, its pharmacology in vivo has not been studied in detail.
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