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Dextro- and levo-methamphetamine?

Survival0200

Survival0200

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Joined
Dec 27, 2005
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When people usually have meth, meth that they've bought from the streets in crystal form, is it dextro-, levo- or racemic methamphetamine? People usually just talk about meth, crank and methamphetamine. No one ever says anything about dextro- or levo- forms of methamphetamine. The selegiline topic made me think about it (selegiline metabolizes into l-methamphetamine and l-amphetamine). So, how is it? I'd of course assume that the street meth would be d-meth, but you never know. Just wanted to make sure.
 
The legal definition of 'ice' is 80% or more d-methamphetamine. (USA)
 
Hahah what the fuck? There's a legal definition of 'ice'?
 
a lot of the meth i've seen around the streets (USA) I'd guess is racemic, feels a fair amount different (dirtier) and less potent as compared to the pharmaceutical pills.

But then again, hey, it's crystal, could be anything?
 
It was always my understanding that levo- amphetamines were non-psychoactive (although sometimes periphically active, i.e. I remember seeing something about levo-(meth?)amphetamine present in vicks inhalers at one time.

Interestingly, levo-methamphetamine is the primary metabolite of deprenyl (although does not exclusively account for deprenyl's effects [1])
 
Coolio said:
Hahah what the fuck? There's a legal definition of 'ice'?
Click to expand...
Indeed.

(C) "Ice," for the purposes of this guideline, means a mixture or substance containing d-methamphetamine hydrochloride of at least 80% purity.

Source

“Ice” methamphetamine is legally defined as high purity (> 80 percent) d-methamphetamine HCl.

Source
 
Street methamphetamine is usually not racemic but rather a mixture of d/l meth.
 
And MSM (methylsulfonylmethane) and MgSO4 (Epsom Salts) and whatever else they cut it with.
 
Helios. said:
Street methamphetamine is usually not racemic but rather a mixture of d/l meth.
Click to expand...

Why would the product be a mixture of d/l meth in any ratio other than 50:50 (racemic)??
- AFAIK the reactions that give rise to meth are either stereospecific or completely non-stereoselective. That is, if you start with one stereoisomer (as precursor), you either get a conservation of stereochemistry, or a complete loss of stereochemical memory that gives rise to a racemic mixture. If you start with a racemic precursor then you get the racemic product unless you take additional steps to resolve the mixture of stereoisomers.
 
Yes, ephedrine and pseudoephedrine are enantiomers, but they have two chiral centers: one chiral center at the -OH benzyl location (which gives rise to the pseudo or sans pseudo designation) and one chiral center at the
N,alpha-methyl location.

The latter chiral center is the determining factor as to whether
d-methamphetamine, l-methamphetamine or a mixture of the two results from the reduction of the starting (pseudo)ephedrine.
 
If meth is made from (pseudo)ephedrine it will always lead to d-meth. (No racemization of (pseudo)ephedrine happening in reaction? Although there are some patents about racemization by refluxing in sulfuric acid.)

If meth is made large scale (of P2P) that leads to 50%/50% racemic l/d-meth.
 
d-pseudoephedrine --> d-methamphetamine

l-pseudoephedrine --> l-methamphetamine

l-ephedrine --> d-methamphetamine

d-ephedrine --> l-methamphetamine


The easiest way to remember IMO is that the natural occurring alkaloids produce the active isomer. Ice is just ReX meth, which is normally done with IPA/acetone to give nice glass-like shards.
 
Also note that: S-meth = d-meth; and R-meth = l-meth.

It might sound like a basic observation but it does catch some people off-guard.
 
DadeMurphy said:
Why would the product be a mixture of d/l meth in any ratio other than 50:50 (racemic)??
- AFAIK the reactions that give rise to meth are either stereospecific or completely non-stereoselective. That is, if you start with one stereoisomer (as precursor), you either get a conservation of stereochemistry, or a complete loss of stereochemical memory that gives rise to a racemic mixture. If you start with a racemic precursor then you get the racemic product unless you take additional steps to resolve the mixture of stereoisomers.
Click to expand...

Exactly what I was thinking. To be anything other than a 50:50 mixture of d & l isomer would require it to be made up specifically using the optical isomerd (which don't make a lot of sense; if your reaction is conserving the stereochemisty you're only going to carry out the reaction to get the d isomer, if it's non stereoselective then you're going to get a 50:50 mixture because of simple probability
 
RxList says: "DESOXYN (methamphetamine hydrochloride tablets, USP), chemically known as (S)-N, a-dimethylbenzeneethanamine hydrochloride"

So, that means Desoxyn is actually dextro-methamphetamine? The fact they tell it's "methamphetamine hydrochloride" makes me think it would be racemic. 8)
 
If your enantioselective catalytic hydrogenation for example yields only an ee of 90% (not uncommon) you'll have 5% of the other enatiomer in it.
 
Survival0200 said:
RxList says: "DESOXYN (methamphetamine hydrochloride tablets, USP), chemically known as (S)-N, a-dimethylbenzeneethanamine hydrochloride"

So, that means Desoxyn is actually dextro-methamphetamine? The fact they tell it's "methamphetamine hydrochloride" makes me think it would be racemic. 8)
Click to expand...

There's nothing in there to indicate racemization. On the contrary, the (S) designates that it is d-meth.
 
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