i'm just gonna throw out some knowledge and hope soembody can wrap it up into a good answer.
at least a few (hell, maybe even all) of the 2C-x (and DOx) compounds are pro-drugs (or pre-drugs), meaning they are inactive until metabolized.
this is the reason for the long onset of DOx; if you wish to prove to yourself that 2C-x are the same, take some harmala, or any other reversable MAOI, prior to ingesting your 2C-x and watch how long it takes to come on; the alpha methyl group makes the chemical harder to metabolize, and this is why DOx is so much more potent than 2C-x, and also why amphetamine is active, yet phenethylamine is not.
also, the positions on the benzene ring have something to do with the activity. 2,5 and 2,6 dimethoxy 4-substituted compounds are active and very potent, while 3,5-dimethoxy 4-substituted are much less so (count mescaline and TMA in this group, even tho its another methoxy group in the 4 position).
mdma is not a pre-drug. we'll assume this is because of the position of the md-ring on the benzene ring.
i dont know where to go from there... but you CANT predict how a drug will be simply looking at structure.
a phenethylamine version of
dmmda, but being methylenedimethoxy instead of methylenedioxy is what you're suggesting?
i dunno if you can do a methylenedimethoxy ring, but looking at
G-3 and
2C-G3, it really makes you wonder what it might be like.
