Sciencemadness Discussion Board

L-Arginine decarboxylation

kratomiter - 26-8-2017 at 14:52

I'm trying to find out a way to form agmatine from L-Arginine. I think that arginine decarboxylase is used at industrial scale, but I need a non-enzymatic pathway.

L-Argine is stable in acid solution, and hydrolizes in solutions over pH 12 (source). Should heating in a mild basic solution do the work? Or maybe just heating dry L-Arginine?

Thank you.

theAngryLittleBunny - 26-8-2017 at 15:37

A good way of decarboxylating amino acids is with carvon, it's a componenet of speamint oil. You just need a high boiling solvent, and a catalytic amount of carvon in it, and then you heat the amino acid to about 150 °C for a few hours. A more aggressive, but faster methode I used was to just cover the bottom of a beaker with carvon, put the amino acid on top and heat it up to about 200°C, it will foam for about a minute and you're done.

UC235 - 26-8-2017 at 19:42

If industry uses an enzyme, it's probably way more effective than the next best approach. generally enzymatic reactions are very inefficient since they are carried out in fairly high dilution and in buffers which requires a lot of concentration and purification.

I would just buy it. Just over $0.10/g for the sulfate isn't worth making yourself, IMO.

Melgar - 26-8-2017 at 20:37

Quote: Originally posted by theAngryLittleBunny  
A good way of decarboxylating amino acids is with carvon, it's a componenet of speamint oil. You just need a high boiling solvent, and a catalytic amount of carvon in it, and then you heat the amino acid to about 150 °C for a few hours. A more aggressive, but faster methode I used was to just cover the bottom of a beaker with carvon, put the amino acid on top and heat it up to about 200°C, it will foam for about a minute and you're done.

Just curious if we figured this out independently or if you read my thread on doing that at a smaller scale?

theAngryLittleBunny - 27-8-2017 at 03:56

Quote: Originally posted by Melgar  
Quote: Originally posted by theAngryLittleBunny  
A good way of decarboxylating amino acids is with carvon, it's a componenet of speamint oil. You just need a high boiling solvent, and a catalytic amount of carvon in it, and then you heat the amino acid to about 150 °C for a few hours. A more aggressive, but faster methode I used was to just cover the bottom of a beaker with carvon, put the amino acid on top and heat it up to about 200°C, it will foam for about a minute and you're done.

Just curious if we figured this out independently or if you read my thread on doing that at a smaller scale?


I first read about it on Erowid, where they found out that cyclohexenone really good decarboxylation catalysist, and carvon has kinda the same structure then cyclohexenone, just with some carbons added, and since this is much easier avaliable then cyclohexenone, most people use that instead.

Melgar - 27-8-2017 at 08:39

Quote: Originally posted by theAngryLittleBunny  
I first read about it on Erowid, where they found out that cyclohexenone really good decarboxylation catalysist, and carvon has kinda the same structure then cyclohexenone, just with some carbons added, and since this is much easier avaliable then cyclohexenone, most people use that instead.

Same here, but I'd only seen it done with turpentine and naphthalene, and didn't know how important the solvent was until I tried it myself with glycerin, propylene glycol, and DMSO. Also by putting a small amount at the bottom and then letting it become its own solvent as it decarboxylated. That was the part I wasn't sure if you'd read my thread on. Only issue is that some amino acids will oxidize at that temperature, so it'd probably be better to use a jar with a lid on loose or something.

kratomiter - 28-8-2017 at 07:33

Thank you for the answer, I'll try with carvone. Agmatine sulphate is no longer available as a supplement in the EU, so I'll gie it a try with bulk L-Arginine, glycerin and spearmint oil.

gatosgr - 23-9-2017 at 07:23

Arginine has very poor solubility in glycerol. What are you using this for ?