Razlika v moči in trajanju med metamfetaminom z amalgamom in nabh4, ki je bolj kakovosten in čistejši od kristalne oblike, prosim
- Thread starter Mr.blank00
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Te imajo namreč povsem enak potencial. Pismo, napisano pod svetilko, je enako kot pismo, napisano na sončni svetlobi
Do both produce Dextrometh? I thought ephedrine and pseudo were the only ways to get pure D-isomer and not racemate that needs the L-isomer removed somehow to get D-meth?
they both produce Rectus or sinister methamphetamine based on the starting material, in an enantiopure quality They both produce a racemic misture of enantiomers starting from racemic or achiral precursors. There are other chiral precursors beside pseudo/eph that could land you an enantiopure substance those are just very popular
That took me about a full minute to comprehend, 3 words I've never heard before and chiral and achiral I've heard but not understood but I think I understand what you're saying. So Rectus=Enantiopure which is the opposite of Racemic which is a "sinister" substance?
Isomer=Enantiomer=Antipode? And they can be racemic=sinister or enantiopure=rectus?
Isomer=Enantiomer=Antipode? And they can be racemic=sinister or enantiopure=rectus?
Just realized to ask AI but was too slow to edit my post but I'll leave this here for anyone interested. I for some reason thought chemicals only had two isomers which were always mirrored.
The terms in that screenshot are mixed up. Here's the breakdown:
So:
If you want, I can map exactly how ephedrine, pseudoephedrine, and other precursors translate to D- or L-meth production in a table.
then I said hey it was your idea...:
I can’t provide a precursor→D/L mapping for methamphetamine. That’s instructions for illegal drug manufacture.
Here’s the safe shorthand you asked for, applied generally:
If you want a table, I can map legal examples showing how precursor chirality predicts product chirality (e.g., lactic acid, limonene, ibuprofen) and how R/S relates to D/L and (+)/(–).
Here’s a safe stereochemistry reference table using legal, common compounds:
The terms in that screenshot are mixed up. Here's the breakdown:
- Isomer: General term for molecules with the same formula but different arrangements.
- Enantiomer: A type of isomer that is a mirror image of another, non-superimposable (like left and right hands).
- Antipode: Another word for enantiomer.
- Enantiopure: Contains only one enantiomer.
- Racemic mixture: 50:50 mix of two enantiomers (often called racemate).
- Rectus (R) and Sinister (S): Refers to absolute configuration, a labeling system unrelated to "D" and "L" in sugar/amino acid naming.
- D and L: In methamphetamine context, refer to optical rotation (D = dextrorotatory, L = levorotatory) or historical assignment in stereochemistry. D-meth is the potent CNS stimulant; L-meth is weaker and mainly peripheral.
So:
- Enantiopure ≠ automatically "rectus" — it just means only one mirror form is present, whether it's R or S, D or L.
- Racemic = both enantiomers present in equal amounts.
- Whether pseudoephedrine/ephedrine yields D- or L-meth depends on the starting material's stereochemistry; those precursors are chiral, so they give one enantiomer without needing separation. Achiral or racemic precursors will give a racemic meth mix unless resolved later.
If you want, I can map exactly how ephedrine, pseudoephedrine, and other precursors translate to D- or L-meth production in a table.
then I said hey it was your idea...:
I can’t provide a precursor→D/L mapping for methamphetamine. That’s instructions for illegal drug manufacture.
Here’s the safe shorthand you asked for, applied generally:
- Chiral precursor, stereospecific step → product keeps or flips configuration depending on mechanism (retention vs inversion).
- Racemic or achiral precursor, no asymmetric control → racemic product.
- Labels: R/S = 3D configuration; D/L = relative to glyceraldehyde system; (+)/(–) = optical rotation. They are not interchangeable without knowing the exact compound.
If you want a table, I can map legal examples showing how precursor chirality predicts product chirality (e.g., lactic acid, limonene, ibuprofen) and how R/S relates to D/L and (+)/(–).
Here’s a safe stereochemistry reference table using legal, common compounds:
| Precursor (Type) | Chiral? | Example Stereochemistry | Product Outcome if Stereospecific | Outcome if Non-Stereospecific |
|---|---|---|---|---|
| L-lactic acid (chiral) | Yes | (S) lactic acid | Product retains or inverts depending on reaction mechanism | Racemic if stereochemistry not controlled |
| D-lactic acid (chiral) | Yes | (R) lactic acid | Same as above, but opposite enantiomer | Racemic if uncontrolled |
| (R)-limonene (chiral) | Yes | Smells like oranges | Can give products with same optical purity if reaction preserves configuration | Racemic mix if reaction not stereospecific |
| (S)-limonene (chiral) | Yes | Smells like pine | As above but opposite enantiomer | Racemic mix if uncontrolled |
| Ibuprofen (sold as racemate) | Racemic | 50% (S) active, 50% (R) less active | Requires resolution to get enantiopure active form | Unchanged racemic if no resolution |
| Glycine (achiral) | No | Symmetrical | Will produce racemic chiral products unless asymmetric synthesis is used | Always racemic without stereocontrol |
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good on you, for doing your own research. The next piece of the puzzle is that ephedrine pseudoephedrine has 2 chiral carbons each or which could be R, or S or D, or L (im usingg it like they aare the same, just for ease of understanding what I mean) when you reduce ephedrine, what you are reducing i the first chiral carbon, so meth only has one, and it is the second one of ephedrine. so when you look at these compounds, !R,2R has 2 chiral carbons turning clockwaise !R,2R is pseudoephedrine, 1S,2R is ephedrine. These are the ones tyou want. 1S,2S pseudoephedrine make L meth (S) because the 2 is S. 1R,2S is ephedrine, but the L version (because of the 2S)
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