I guess I don't necessarily understand what's being asked. Are you just asking what analogs exist? What do you want to know about them? Are you looking for a new psychedelic, a new PTSD-type therapeutic similar to (but distinct from) MDMA?
It just seems kind of odd to ask what compounds exist.
Ive always been curious about (How do I put this). How far back "we" could go. For example starting with Benzene (Or its pre) and forming molecules. (Im no chemist obviously).
When you say Propyl Hexadrine though, I extract from Benzedrex with MA and any Non Polar solvent, Just a theory I would never do ANYTHING against the law but I feel like PHEX and Amphetamine (Just an example) are SO structurally similar couldn't there be a usefulness there? Also Meth is reduced industrially to Synth it.. Weird.
I just feel there's a use for it that hasn't been realized. It'd take a smarter man than me though. Sorry If that was irrelevant.
They're actually not that structurally similar. Other than having six carbon atoms, saturated vs. aromatic ring systems have about as different of chemistry as you can get. They don't participate in the same reactions, and their binding to a receptor is different as well. For a 6-member ring system, aromatic groups (like phenyl groups) tend to have a cloud of electron density above and below the ring, and are subject to something called "ring current". Because of these factors, they tend to have a larger partial positive charge on the aromatic hydrogens vs. a cyclohexane ring. This causes them to interact in a few notable ways in receptors; they can participate in pi-stacking, where the aromatic ring of the drug and a pi system in the receptor binding pocket stack on top of one another, you can also have cation-pi interactions, where a cation in the receptor pocket forms a partial bond with the cloud of electron density above and below the ring. They also have entirely different conformations, with an aromatic ring being flat and a cyclohexane ring being kinked into a "chair" confirmation, although it can adopt others.
So, yeah, the drugs look pretty similar, but that's actually a major modification to go from a fully saturated to a fully unsaturated ring system, and it makes their pharmacology distinct, though similar.
By the way, there's a lot of medicinal chemists who do exactly what you're talking about; they strip down drugs to find out which structural features are necessary, which can be removed without changing activity, etc. One of my favorite examples is the benzomorphan/morphinan/dxm structures.
Just look at these in order:
https://en.wikipedia.org/wiki/Pentazocine ,
https://en.wikipedia.org/wiki/Morphinan ,
https://en.wikipedia.org/wiki/Dextromethorphan