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Acetylation of Loperamide and Methadone

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Paregoric Kid

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can an acetyl group be added to methadone and loperamide? with methadone would you get LAAM, or alpha-d-acetylmethadol or what would it create?
I've read that acetylating loperamide might create O-acetyl loperamide, any info on this?
thanks
 
You can acetylate any (barring things like steric hinderance) compound with a free hydroxy group. Generally something like acetic anhydride is enough to do the trick. Now methadone doesn't have a hydroxy group to acetylate* - LAAM is O-acetyl methadol, methadol being what you get when you reduce the keto group in methadone to a hydroxy group.

* It is technically possible to acetylate a keto group because of a thing called keto-enol tautomerism where a keto group is one of two resonant states; the other being an alcohol with a double bond attached to the carbon bearing the hydroxy group. This is the more unstable of the two states though - acetylation would require a much more complicated synthesis. The only case I can think of in a drug is acetyldihydrocodeinone, which is basically hydrocodone that has been acetylated as the enol form (probably to enhance passage across the BBB)
 
What F&B did not mention (but implied) is that Loperamide has a free OH group ;).

I would be interested in knowing what happens with acetylated loperamide...
 
sorry to add more questions but what is the difference between LAAM and acetylmethadol?
also would reacting acetic acid with hydrocodone create thebacon (acetylhydrocodone)?
 
I remember reading a post once where someone said they took vinegar and mixed loperamide in it, I forget the specifics of what else they did but they said it produced opioid effects. perhaps he had a bit of O-acetyl loperamide?
 
Is it known how the effects of acetylcodeine are? Since it is a pro-drug I expect it to be different from heroin for example, but how so?
 
Paregoric Kid said:
I remember reading a post once where someone said they took vinegar and mixed loperamide in it, I forget the specifics of what else they did but they said it produced opioid effects. perhaps he had a bit of O-acetyl loperamide?
Click to expand...

That would be interesting! Mixing vinegar and loperamide to get an opiate effect.... But it sounds too easy..
 
^

was it an opiate user , paregoric?

if he wasn't loperamide in itself could very wel give opiate effects in a high dose (although no euphoria) , just read the pamphlet that comes with it.
 
would vinegar allow the loperamide to pass the bbb? If so i have a box of immodium downstairs and a bunch of rice vinegar :)
 
Vinegar & loperamide isn't goint to produce O-acetyl loperamide, no matter how much you want it; there's too much water present, so the reaction equilibrium is going to favour them staying as loperamide & acetic acid. To O-acetylate it you're going to need something like glacial acetic acid or acetic anhydride...
 
Reflux of loperamide with some GAA or acetic anhydride ought to do the job, don't you think? you have me curious now.
 
Literature procedures nearly always use acetyl chloride/anhydride. Why would anybody go the extra mile if all they had to do was use glacial acetic acid? Discussion of synthese is a prerequisite for thread closure.
 
Well, results should be in soon, what sort of strength do you predict o-acetyl-loperamide to possess?

I have been quite curious about the potential of loperamide for a while now, I intend to start low, but how low is low, for this compound? 1-2mg?
 
I was talking about the o-acetylated version, not loperamide itself, I started with 2mg, give or take the traces that may or may not have been lost on the petri dish/test tube surface etc.

2mg loperamide was refluxed with 1ml of GAA, and then neutralised by adding Ca(OH)2 until CO2 evolution ceased, this was then diluted and administered rectally after dropping a turd.

T+ 30min, slight to moderate opiate effects are noticeable, no nausea, and breathing rate normal to very slightly reduced, pulse slightly slowed but npot by much.

Subjectively, relaxing, typical mild mu-opioid effects, higher doses will be trialed as and when the test monkey can be bothered=D
 
^ Very interesting. Let us know what happens. You need an opiate-naieve user.
 
I am not opiate naieve, I have done my fair share, I like opioids a lot, but I do not use at ALL regularly, and as of now, have zero tolerance.

Its a tough job, but somebody has to do it=D
 
:) this thread holds promise i hope some progress can be made before it gets locked:(
 
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