chemrox - 20-11-2007 at 22:02
I looked at creatine and creatinine to try and figure out the mechanisms involved as part of my ongoing education/review. The
nomenclature/classificaion of the two entities are bothering me. What are they? Creatine can't be an alpha amino acid.. I don't have a name for the
type of compound creatinine is.
http://www.orgsyn.org/orgsyn/default.asp?formgroup=basenpe_f...
[Edited on 20-11-2007 by chemrox]
not_important - 20-11-2007 at 22:50
Creatine is derived from glycine, and is a substituted alpha amino acid - amino type nitrogen on the alpha carbon. It's also a guanidine derivative.
The conversion to creatinine is just the formation of an amide linkage, creatinine at heart being an imidazol.
chemrox - 21-11-2007 at 19:46
Thanks,n_i, I see the derivation all right, but does it fall into one of the heterocycle classifications I didn't spot? I don't see alpha amino acid,
it looks to me like the first amine position is beta to the carboxylic acid group. However, if you consider orientations in space, as opposed to
bonding, the tail amino group can form a zwitterion with the acid proton. Is that how it works?
MagicJigPipe - 21-11-2007 at 20:15
I just looked it up on wikipedia and it does appear to work that way.
not_important - 21-11-2007 at 20:15
Look at the biosynth http://en.wikipedia.org/wiki/Creatine and see that glycine in there - alpha amino acid. True, that's not the nitrogen involved with the
zwitterion, but it's still attached to the carbon alpha to the carboxylic group.
Consider the more formal names - 2-(carbamimidoyl-methyl- amino)acetic acid and (α-methylguanido)acetic acid. You've got two simple
functionalities to start naming from, acetic acid wins in this case, and there's no base heterocycle to to use.
Creatinine is 2-amino-1-methyl-5H-imidazol-4-one, the imidazole ring being the heterocycle for the base name.