Armesocarb is the R-enantiomer of mesocarb. Mesocarb itself has been used as a recreational psychostimulant in post Soviet states and is therefore controlled in many countries. It's also banned by WADA suggesting it may have performance enhancing effects similar to those seen with more common stimulants. Most available sources suggest it is less reinforcing than amphetamine, but still produces stimulant effects to allow recreational use.
Its mechanism is not identical to methylphenidate, however. Mesocarb acts as a negative allosteric modulator and non-competitive inhibitor at the dopamine transporter (DAT). The dopamine transporter does not have a single binding site; instead, it has multiple binding and regulatory sites that can influence transporter activity in different ways.
Common monoamine reuptake inhibitors such as cocaine and methylphenidate are competitive inhibitors. This means they bind to the primary substrate site on DAT, competing for occupancy with dopamine, directly blocking dopamine reuptake. This effectively disables the transporter, leading to a rapid increase in synaptic dopamine and pronounced psychostimulant effects.
Mesocarb is non-competitive, meaning it binds to a different site on the transporter. Dopamine can still bind to DAT because mesocarb doesn't compete for occupancy, but transporter function is impaired. As a result, dopamine still accumulates in the synapse, but generally in a slower and less intense manner.
Mesocarb has also been found to act as a negative allosteric modulator, meaning it binds to a regulatory site on DAT and further reduces transporter efficiency without completely blocking it. This produces a milder and smoother dopaminergic effect compared with classical stimulants.
Would mesocarb be suitable for recreational use? Possibly, but based on its pharmacology it would likely be less euphoric and less reinforcing than methylphenidate or amphetamine, and therefore probably less desirable for that purpose.
