0
$\begingroup$

enter image description here

What do the dots mean in HN.CO.CH3 connected to the second carbon of N- Acetylglucosamine? And what do the N and acetyl indicate?

$\endgroup$
  • 1
    $\begingroup$ What is glucosamine? What is an acetyl? The acetyl is connected to the amine at the nitrogen atom, hence N-acetyl. These "dots" (they look more like blobs to me) are just a simple covalent bond. Why they look like blobs I have no idea. $\endgroup$ – Karl Jan 5 at 12:46
  • 3
    $\begingroup$ These don't look like dots to me, more like en-dashes used for denoting chemical bonds (e.g. $\ce{HN-CO-CH3}$). Probably they were chosen short by the typography in order to fit an entire structure on the page. N- indicate the substituent on the nitrogen, and the task of finding what is acetyl is I leave to you:) $\endgroup$ – andselisk Jan 5 at 12:47
  • 3
    $\begingroup$ They look more like dashs to me, a dash is a common symbol for a single bond $\endgroup$ – Nuclear Chemist Jan 5 at 13:14
6
$\begingroup$

These are not dots. They actually are single bonds though I do not know why they are printed that way. As such, they should be represented by a half-long dash (called EN DASH in Unicode).

In the name N-acetylglucosamine, acetyl means that a hydrogen atom has been replaced an acetyl group (i.e. –CO–CH3) and that the replacement occurred on the nitrogen (aka "N") atom.

Overall, it means something like: "consider glucosamine but replace one hydrogen on the nitrogen atom by an acetyl group". This is the standard "substitutive naming" defined by the IUPAC.

$\endgroup$

Your Answer

By clicking "Post Your Answer", you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.