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guy
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Is MSG useful for anything?
I found bags of pure MSG at my grocery store. I wonder if it can be used for anything.
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Nerro
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What the hell is "MSG"?
#261501 +(11351)- [X]
the \"bishop\" came to our church today
he was a fucken impostor
never once moved diagonally
courtesy of bash
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guy
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Not familiar with chinese food eh? ![:)](./images/smilies/smile.gif)
MSG is monosodium glutamate.
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roamingnome
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a destructive distillation may libarate CO2 and NH3 ![:o](./images/smilies/shocked.gif)
although one would be basic and the other acidic conditions huh?
http://cameochemicals.noaa.gov/chemical/20715
hmmm toxic gases like what?
[Edited on 8-9-2007 by roamingnome]
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Destructive distillation of dry MSG will produce an impressive foul odor, though I don't recall smelling ammonia when I tried it.
PGP Key and corresponding e-mail address
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Sauron
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You should be asking yourself what you can do with glutamic acid. A peek at Merck for starters ought to be instructive.
Title: Glutamic Acid.
CAS Registry number: [56-86-
CAS name(s): L-Glutamic acid Additional name(s): Glu; E; glu ta min ic acid; ( S )-2-aminopentanedioic acid; alpha-aminoglutaric acid; 1
-aminopropane-1,3-dicarboxylic acid Trade name(s): Glutacid; Glu ta minol;
Molecular formula: C 5 H 9 NO 4
Molecular weight: Percent Composition: C 40.82%, H 6.17%, N 9.52%, O
Literature references: Non-essential amino acid for human development; referred to as an excitatory amino acid (EAA) due to its role in
neurotransmission. Isoln from wheat gluten: H. Ritthausen, J. Prakt. Chem. 99, 454 (1866). Early chem istry and biochemistry: Amino Acids and
Proteins, D. M. Greenberg, Ed. (Charles C. Thomas, Springfield, IL, 1951) 950 pp. , passim ; J. P. Greenstein, M. Winitz, Chemistry of the Amino Acids
vols 1-3 (John Wiley and Sons, Inc., New York, 1961) pp. 1929-1954, passim ; C. W. Huffman, W. G. Skelly, Chem. Rev. 63, 625 - 644 (1963).
Interconversion from L-proline: S. Yoshi fuji et al., Tetra hedron Letters 21, 2963 (1980). Determn in serum: C. D. Stalikas et al., Eur. J. Clin.
Chem. 32, 767 (1994); of natur ally occurring levels in food: D. H. Daniels et al., Food Addit. Contam. 12, 21 (1995). Identification as excitatory
neuro transmitter: D. R. Curtis et al., J. Physiol. 150, 656 (1960). Review of biosynthesis: A. Hamberger et al., Adv. Biochem. Psychopharmacol. 27,
115-126 (1981); of metabo lism and associated disorders: S. B. Prusiner, Ann. Rev. Med. 32, 521-542 (1981). Review of receptor binding: P. A. Briley
et al., Mol. Cell. Biochem. 39, 347 (1981). Review as neurotransmitter: B. Engelsen, Acta Neurol. Scand. 74, 337-355 (1986); E. Marmo , Med. Res. Rev.
8, 441-458 (1988). Review of role in learning and memory: W. J. McEntee, T. H. Crook, Psychopharmacology 111, 391-401 (1993); in Parkinson's disease:
M. S. Starr, Synapse 19, 264-293 (1995). Books: R. Powell, Monosodium Glutamate and Glutamic Acid (Noyes Dev. Corp., Park Ridge, N.J., 1968) 256 pp.;
Glutamic Acid: Advances in Biochemistry and Phys iology, L. J. Filer, Jr. et al., Eds. (Raven, New York, 1979).
Properties: Orthorhombic, bisphenoidal crystals from aq alc. d 4 20 vac 1.538 . Melts 160degrees with conversion to to L-pyrrolidonecarboxylic acid.
Sublimes at 200degrees. [alpha] D 22.4 +31.4degrees (6 N HCl) . pK prime 1 2.19; pK prime 2 4.25; pK prime 3 9.67. Soly in water (g/l); 8.64
(25degrees); 21.86 (50degrees); 55.32 (75degrees); 140.00 (100degrees). Insol in methanol, ethanol, ether, acetone, cold glacial acetic acid and
common neutral solvents. Density: d 4 20 vac Rotation: +31.4 Derivative: Hydro Molecular Formula: C 5 H 9 NO 4 CAS Registry: [138-15- Trade name(s):
Acidulin (Lilly) , Acidoride (Abbott) , Hypo chylin, Antalka, Aciglumin, Pepsdol, Glutamidin, Acidogen, Aclor, Gastuloric, Glutan-HCl (Lederle) ,
Glutasin (McNeil) , Hydrionic (Upjohn) , Muri amic. Properties: Orthorhombic bisphenoidal plates, dec 214degrees. [alpha] D 22 +24.4degrees (c = 6) .
Rotation: +24.4 Derivative: Sodium salt, see Monosodium Glutamate. Derivative: Magnesium salt hydrobromide Molecular Formula: C 10 H 17 Br MgN 2 O
8 .H 2 O Additional name(s): magnesium glutamate hydrobromide, magne sium bromoglutamate, Trade name(s): Psicosoma (Trommsdorf) , Psycho-Soma (Boots)
, Psychover lan (Verla) .
Derivative: DL- CAS Registry: [617-65-
Properties: Ortho rhombic crystals from water, 225-227degrees (dec). d D 20 1.4601 . Soly in water (g/l): 20.54 (25degrees); 49.34 (50degrees); 118.6
(75degrees); 284.9 (100degrees). Sparingly sol in alcohol, ether, petr ether. Density: d D 20
Derivative: D- CAS Registry: [6893-26- Properties: Shiny leaf lets from water. [alpha] D 20 minus30.5degrees (c = 1.00 in 6 N HCl) . Rotation:
minus30.5 THERAP CAT: Exptl antiepileptic; hydrochloride as gastric acidifier; magnesium salt hydrobromide as anxiolytic.
Sorry, Merck Index Copy Text function is for shit.
Now, as to a suggestion for a project:
1. Get rid of the amino group
2. Add a hydroxyl group to the 3-position then oxidize it to a carbonyl. You will then have b-ketoglutaric acid, aka acetonedicarboxylic acid.
For what you can do with acetonedicarboxylic acid see the threads on DINA
You will have avoided the usual route to acetonedicarboxylic acid, which is treatment of citric acid with oleum. Oleum being hard to come by, this is
in my opinion a Good Thing.
[Edited on 9-9-2007 by Sauron]
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guy
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How to get do you rid of the amino group? I would think maybe heating it in acid to pull it off. Then now I would have 3-pentenedioic acid? Now add
water to it using acid catalyst to get 3-hydroxypentanedioc acid, and then oxidize it.
I'll probably also get the alpha-ketoglutaric acid too.
Would that work?
edit:
Or perhaps nitrous acid may do a better job of removing the amino group.
[Edited on 9/9/2007 by guy]
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Sauron
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Sounds like a job for Comprehensive Organic Functional Group Ytansformations by Alan Katritzky et al.
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vulture
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Methylate with methyliodide and substitute with OH-.
Perhaps diazotization?
One shouldn't accept or resort to the mutilation of science to appease the mentally impaired.
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not_important
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MSG is a low cost OTC organic, I bought a 25 kg sack for about $US 15 .
Check out the reactions of amino acids. Unfortunately many of these are "messy" reactions, producing a number of products as a mixture.
MSG can be decarboxylated to gamma amino butyric acid, there are threads on amino acid decarboxylation.
Adding MSG to Bacillus thuringiensis formulations increases the effectiveness of BT as an insecticide.
MSG forms complexes with a number of metals; sometimes from the amino group, a few from the two CO2H groups, others use both the acid and amino.
Mixing solutions of CuSO4 an MSG gives a deeper blue solution, not as dark as with strong aqueous ammonia but still a definite change; the complex
can be crystallised.
Chlorine bleach will oxidise the NH2 to give the alpha keto acid, which readily decarboxylates to the aldehyde, succinate semialdehyde in this case.
This is an annoying compound that readily condenses and polymerises to gunk, but it can be oxidised to succinic acid or reduced to gamma hydroxy
butyric acid.
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Nicodem
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I think amino acids form hydantoins by heating them with urea. Since urea is also easily available you could try and maybe get
hydantoin-5-ylpropanamide (SMILE: O=C1NC(CCC(N)=O)C(=O)N1 ). Otherwise, the hydantoins form from amino acids when they are treated with cyanates in
acidic aq. solution (NaOCN or KOCN can easily be prepared in a home lab). This would however yield hydantoin-5-ylpropanoic acid instead. Guy, if you
are interested I can search the literature for a reference if such reactions exist on glutamic acid itself.
Alternatively you might prepare pyroglutamic acid from it.
Quote: | Originally posted by not_important
Chlorine bleach will oxidise the NH2 to give the alpha keto acid, which readily decarboxylates to the aldehyde, succinate semialdehyde in this case.
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As far as I know alpha-keto carboxylic acids loose carbon monoxide by heating: R-CO-COOH => R-COOH + CO
Are you sure you can decarboxylate alpha-keto acids into aldehydes? Do you have any such example or reference?
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not_important
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Well, me best reference is a couple of books that are A) packed away in storage, and B) I'd don't have a functional scanner right now. So I can't give
you the ones that lead me to play around with it.
But the following and attached are related. Note that it's not a high yield reaction, nor particularly clean, but given the low cost of the raw
materials that can be tolerated and it can be interesting to play around with.
K. Langheld Ber. 42, 2360 (1909).
http://www.cazv.cz/attachments/3-Adamiec.pdf
http://www.erowid.org/archive/rhodium/chemistry/p2p.strecker...
using fenton oxidation, which tends to oxidise the aldehyde to carboxylic acid
http://www.jbc.org/cgi/reprint/266/26/17201.pdf
There are a lot of related reactions, using various oxidation reagents including copper salts, poly-ketones, and sugars. The reactions are classified
as Strecker degradations, oxidative decarboxylation. deamination decarboxylation, and other terms; there are enzyme based variants as well.
Attachment: 1-Rossner.pdf (104kB) This file has been downloaded 1612 times
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guy
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I am interested in making succinic acid. How would the decarboxylation of alpha-ketoglutamic acid be done?
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guy
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I think I have made keto-glutaric acid. I oxidized glutmaic acid with NaOCl. There was gas evolution.
I tested a few milligrams of the substance in about 400mL water and a few drops of FeCl3 soln and obtained a pale yellow color.
I tried the test with a few milligrams of glutamic acid and did not get any colors.
So is this a good test to show that I have had keto-glutaric acid. And if it is, is the color of the complex due to the enol complex with iron?
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not_important
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From reports such as http://www.biochemj.org/bj/030/0484/0300484.pdf hypochlorite tends to give the one carbon shorter aldehyde or nitrile, via decarboxylation. I
suspect that the succinic semialdehyde can form a complex with FeCl3 through its hydrate form.
Pale yellow doesn't sound like much complex formation, though. You could do some tests for aldehydes, including the simple addition of dilute KMnO4.
You could also run the reaction on a larger scale and test the gases given off for CO2.
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guy
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Oh it is a complex formation. Its only pale because it was very very dilute. FeCl3 is colorless when dilute, and when I put a few drops of the
'compound' in a yellow color forms.
I will test for aldehydes.
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guy
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I used Fehling's test and got no results. I think this may be 3-cyanopropanoic acid. I think the cyano group forms a complex with the iron.
Is there a good test for nitriles?
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Ozone
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This looks interesting:
http://en.wikibooks.org/wiki/Applied_Science_BTEC_Nationals/...
"Neutral" Iron (III) Chloride
To 1 g or 1 cm3 of the test substance add "neutral" iron III chloride dropwise until no further colour change - if any - occurs. If in doubt perform a
control or blank test using water in place of the test sample.
Observation Inference
Violet or blue colour. Phenol or phenol derivative
Red/violet colour 4-nitrophenol
Yellow colour Salt of aliphatic hydroxycarboxylic acid
Buff ppt. Salt of aromatic carboxylic acid
You will also get nice purple and red with enols such as 2,4-pentanedione. The yellow color would be consistent with hydroxycarboxylic acids
(glutaric, for example).
Glyceric acids will not reduce Fehling's reagent.
For nitriles, try boiling the sample (small) in a test tube with ~10% NaOH and check for alkali with moistened litmus (amides and nitriles). Then
check out the vapor with CuSO4 saturated papers to detect NH3. This test should also be positive for 1° amines and quats.
Cheers,
O3
[Edited on 17-10-2007 by Ozone]
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guy
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I mixed it with NaOH soln and I definitely got an ammonia smell.
I guess this is pretty consistent with the paper not_important gave about nitriles forming.
I just haven't found any sources that say Fe3+ can complex with a nitrile, but I think it is a good possiblity given that thiocyanide and cyanide can
complex with iron.
[Edited on 10/17/2007 by guy]
[Edited on 10/17/2007 by guy]
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Quantum_Dom
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1-Acidification of MSG to glutamic acid.
2- Decarboxylation of glutamic acid with a high-boiling point solvent and cyclohexanone acting as a catalyst to obtain gamma-aminobutyric acid (GABA).
3-Conversion of GABA to GHB (gamma-hydroxybutyric acid) using the Sandmeyer reaction.
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jarynth
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An attempt was made at reacting food grade MSG with household bleach. The small white crystals dissolved readily, while the mixture warmed up
spontaneously with slow evolution of ammonia gas. After 10 min the clear solution was heated to below boiling point, and subsequently irradiated with
400W MW for 4 min. The solution turned yellow-brown, ammonia production increased with boiling, and an indistinct filled turkey smell was also
registered. Small needles formed in the slurry upon evaporation of the solvent.
If we really got the alpha-ketoglutarate, then poop germs can help us now:
"A cell-free enzyme preparation from E. coli decarboxylates a-ketoglutarate
to succinate and CO2 in the presence of malonic acid as an inhibitor
of succinate oxidation."
http://www.pnas.org/content/34/11/491.full.pdf
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ScienceSquirrel
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Here is an interesting attempt at the preparation of succinic acid from glutamic acid;
http://monocerosfour.livejournal.com/3545.html
I reckon with a bit of work it could be made to work
Interestingly succinic acid is very soluble in hot water but not very soluble in cold water.
http://www.jtbaker.com/msds/englishhtml/S7226.htm
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Baphomet
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You may be interested to know that glutamate acts as the ammonia source for reductive amination within organisms.
The reaction is carried out by an enzyme (the hard part!) and pyridoxal phosphate (easy - vitamin B6).
More info is available n:
"Principles of Biochemistry"
Nelson, D. L., et al.
IBSN 1-57259-153-6
It would be interesting to try this out one day and make some nitro from acetone.. But I have not had much success with enzymes thus far
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UnintentionalChaos
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Dredging up the dead here, but I have requested a paper over in references on the use of TCCA (trichloroisocyanuric acid, not CC ot TCT or whatever
the names are for the cyclic trimer of cyanogen chloride with the chlorine on the carbon, not the nitrogen) for oxidative decarboxylation of
alpha-amino acids to the one carbon less nitrile which in the case of glutamic acid here would hydrolyze to succinic acid...leading to a way for OTC
N-bromo succinimide!
I personally am interested in it as a way to reduce the length of an epoxidized ricinoleic acid (by intermediacy of the amide) by one unit followed by
hydration of the epoxide and oxidative cleavage of the vicinal diol thus formed into suberic acid and
beta-keto-nonanoic acid (which should readily decarboxylate to methyl hexyl ketone (and then possibly cleaved to heptanoic acid) yielding another chem
to put aside for another day). Destructive distillation of the magnesium or zinc suberate is supposed to yield up to 60% of the theoretical of
cycloheptanone.
Also, I hate to break it to you, quantum_dom, if you're still around, but 1: you can buy GABA in the health food store by the pound and 2: ever heard
of carbocation rearrangement? Aliphatic diazo compounds fall apart really fast in solution forming a primary carbocation. This will largely undergo a
1,2-hydride shift forming the more stable secondary carbocation which then undergoes nucleophilic attack by water forming beta-hydroxy butyric acid.
good luck isolating the 5% or so that does not undergo the hydride shift before nucleophilic attack.
[Edited on 11-10-08 by UnintentionalChaos]
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Nicodem
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Quote: | Originally posted by UnintentionalChaos
2: ever heard of carbocation rearrangement? Aliphatic diazo compounds fall apart really fast in solution forming a primary carbocation. This will
largely undergo a 1,2-hydride shift forming the more stable secondary carbocation which then undergoes nucleophilic attack by water forming
beta-hydroxy butyric acid. good luck isolating the 5% or so that does not undergo the hydride shift before nucleophilic attack.
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Alpha- to delta-aminoacids form lactones after nitrosation due to the intramolecular substitution (cyclisation) of the intermediate diazonium compound
thus forming 3 to 6 membered rings - a process which is much faster than carbocation formation (which is energetically less favoured) and consequent
rearrangement/fragmentation. The yields are generally high. See literature for examples and more info.
…there is a human touch of the cultist “believer” in every theorist that he must struggle against as being
unworthy of the scientist. Some of the greatest men of science have publicly repudiated a theory which earlier they hotly defended. In this lies their
scientific temper, not in the scientific defense of the theory. - Weston La Barre (Ghost Dance, 1972)
Read the The ScienceMadness Guidelines!
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