No drug can be more synthetic than another. It's either man made or it's not.
I am guessing by man-made you mean 'invented by man / not found in nature'. If that's the case, then it would be instructive to mention that even this distinction, while real, means basically nothing. By the way, just to be clear, I quoted you toastmann because you bring up a point I want to expound upon, but I'm not calling you out in a hostile manner. Just to make sure this post doesn't get misunderstood.
By this I mean that some compounds were invented by a chemist either just coming up with a brand new structure in their head, or much more likely by a chemist looking at an existing molecule and modifying the structure in their mind / on paper, and then using their synthetic abilities to make that altered molecule a reality. Other compounds are found in nature, and exist independently of mankind. But there is not any difference between things that were invented and things found in nature besides their source of discovery. They're all just chemicals, and they operate in the body and react to other chemicals based on the same set of physical laws.
There's another distinction that some people make, and that is whether a compound was made by a plant biosynthetically using enzymes or whether it was made in a lab. This relates to an actual sample of a drug, whereas the distinction between 'invented by man' and 'found in nature' is a more theoretical distinction. But this second distinction is just as equally meaningless as far as a drug's function or whether or not it is healthy to use as is the distinction based on invention versus discovery. Some people I have met would take mushrooms, but wouldn't take 4-HO-DMT because it was synthesized in a lab. This is just silly, and I will illustrate the silliness as follows, including both the distinction between invention versus discovery as well as between whether an actual physical sample was synthesized in a lab or in a plant cell, all rolled into one:
There is a compound called N,N-methylethyltryptamine, or MET. This compound was invented, not discovered, and doesn't exist in nature as far as we know. There's another compound called 4-hydroxy-N,N-methylethyltryptamine, abbreviated as 4-HO-MET. As with the unsubstituted MET, 4-HO-MET was also invented, not discovered, and that distinction has held for this compound as well because we have not subsequently discovered it in nature. Since both of these compounds were invented in the mind of Sasha Shulgin, by conceptually modifying the structures of DMT and 4-HO-DMT, they are only created in labs, not in plants, animals, or fungi. So by certain people's measures they're not healthy to use either because they are not found in nature, or because they can only be produced in a lab, or both.
But now things get complicated! It just so happens that if you enrich the substrate upon which psilocybin-containing mushrooms grow with MET, they will take it into their body (mycelium), and here is where it gets interesting. It turns out that the enzymes that take DMT and hydroxylate the 4-position to make 4-HO-DMT, also known as psilocin, are not selective. Those enzymes it turns out will take almost any N,N-disubstituted tryptamine (provided the alkyl substitutions aren't super-long) and stick the hydroxy on the four position, just as the enzymes do to the naturally-occurring, discovered-not-invented compound DMT, turning it into the also naturally-occurring, discovered-not-invented compound 4-HO-DMT.
So in summary, if you take MET and you put it into the stuff magic mushrooms grow on, they will take it and the enzymes that ordinarily take DMT and make 4-HO-DMT will turn the MET into 4-HO-MET.
So the question to the people who make silly distinctions about 'natural' or 'synthetic' things being healthy or not, is what category does the 4-HO-MET that is produced fall into? You have a compound that was invented, not discovered, and is only synthesized in a lab (or better to say 'not found in nature'), that is turned into another compound that was invented, not discovered, and is also not found in nature, by a fungus. So even though both compounds were invented, and neither is found in nature, you can 'hijack' magic mushrooms to take the first compound and make it into the second using a purely biosynthetic, 'natural' process, using enzymes.
So is 4-HO-MET then still 'synthetic'? Obviously the fact that it was invented, not discovered doesn't change, but if you can use a mushroom to perform the 4-substitution, is the resulting compound natural or synthetic?
The whole distinction is goofy. I get that it's based upon earnest beliefs that natural things are safe where man-made things are not, but it isn't that black and white. Surely strychnine, which exists in nature, is not safe. And there's the whole panoply of invented psychedelics that are 'synthetic' but are perfectly safe at ordinary doses. Unfortunately this false dichotomy is very strongly ingrained in the minds of its proponents, and often in my experience no amount of factual information will shift people's views on this matter.
So you wanted to list the various types of LSA containing seeds? Okay.
Btw I would call bromomescaline 3,5-dimethoxy 4-bromophenethylamine. Probably a good compound.
I don't know if there would be enough room there for the bromine. Look up 'steric bulk', as I could be wrong. I'm not an expert here (on steric bulk), chem major or not, but my gut and what training I do have says that either there's simply just not enough room so it couldn't exist, or that it could theoretically exist but that the synthesis would be just too absurdly difficult / that it would be too unfavorable of a product in the reaction, yielding garbage substitutions you don't want and little if any of what you do want.
Maybe there's enough room there for a chlorine? I mean, it would certainly be more likely than bromine, chlorine being smaller, but I still couldn't say for sure if even the 4-chloro version could exist.
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