Here: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1375232/#__sec3title they write
"The ‘e’ was dropped when it [thiamine] was found that it was not an amine."
How is it so that thiamine is not an amine if it does have an amine group? Or is it meant that the amino group is not the main group (in the sense of importance for naming)? So because there is the thiazolium ring, it's not considered as amine? Or is it because the amine group is bound to the pyrimidine and thus it doesn't behave as aliphatic amine?
(but are aromatic amines not considered as "true" amines?)
I feel the authors are completely mistaken for this historical explanation. The spelling thiamin was proposed perhaps by German influence to drop the e in amines (e.g. Aniline is Anilin in German). It certainly has an amine group.
The multi-volume Oxford English Dictionary traces the origin (not the desk one)
1937 "Jrnl. Amer. Med. Assoc. 18 Sept. 952/1 Dr. Jansen has been very cooperative in discussing the matter of nomenclature for vitamin B1 and suggested..that Dr. R. R. Williams..propose a name based on the chemical structure. Dr. Williams..proposed the term Thiamin Chloride."
Although thiamin(e) does have an amino group, it is an aromatic amine (aryl amine) and therefore not as reactive with the sort of amine-modifying electrophiles used to prepare conjugates as an aliphatic primary amine, and not as basic.
Historical note: the word vitamin was originally coined (as vitamine) based on the idea that the nutrients essential to life that prevented nutritional deficiency diseases (such as beriberi, which is prevented by thiamin) would all contain amino groups, which was mistaken so the e was dropped.
You MUST know that the name 'vitamin' comes from the fact that were originally called 'vital amines'. Current literature drops the 'e' - so it's thiamin. Lots of vitamins do not incorporate an amino group - eg vitamin D, biotin. The amino group (on the pyrimidine ring of thiamin) does have a mechanistic function - as a positively charged group it probably stabilises the reactive ylid on the thiazolium ring. To test this we replaced the amino group with a hydroxy - and the compound was inactive. You could check this ( Thiamine Biosynthesis in Yeast - Evaluation of 4-Hydroxy-5-hydroxymethyl-2-methylpyrimidine as a Precursor; R.L. Baxter, A.B. Hanley and H.W.-S. Chan; J. Chem. Soc., Perkin Trans. I, 1990, 2963-2966.)
so you mean, that the e was dropped in thiamin because it was dropped in vitamin because not all vitamines are amines (but has nothing to do with thiamin not being amine)?
OK guys.... end this, let's not pedantic. Thiamin, thiamine, vitamin B1 - everyone in the field knows what the molecule is...OK. There is an aminopyridine in the structure. So there is an amino group (everyone agrees...good). So end this.
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