Original post · Sun, February 3, 2013
Investigation into stereoselective pharmacological activity of phenotropil. (phenylpiracetam)
u/MisterYouAreSoDumb
http://www.ncbi.nlm.nih.gov/pubmed/21689376
the antidepressant and increased locomotor activity relies on both R- and S-phenotropils, but the memory-improving activity is only characteristic of R-phenotropil.
This makes sense, since the benzene ring off the phenylethylamine structure is the same in both enantiomers. I postulate that the norepinephrine and dopamine affinities come from the benzene side of the molecule, and the NMDA modulation comes from the piracetam side with the open amine group.
~~This is what I believe the R and S isomers look like.~~
This site says that C5 is the chiral center, so my picture should be accurate. (I am not certain my S and R labels are correct, though)
Since the stimulant/anti depressant effects are present in both isomers, but the memory enhancement is only present in the R, I think it's safe to postulate that the NE and DA effects are from the benzene side. This would also explain why the methylenedioxy ring on MDMA reduces the substances affinity for DA in comparison to methamphetamine. It also fits with 6-APB having a higher DA affinity than MDMA. The benzofuran ring has one less oxygen atom than the methylenedioxy ring, which causes the substance to have a higher DA affinity and less 5-HT affinity. The benzene is what has NE and DA affinities.
I am not a chemist, so these are just postulations at this point. Does anyone see any holes with my thinking?