[fotia]

Hi,
I was wondering how NMR works.
Recently, i got a research compound from a chinese company who purportedly sold "ritanserin" and "eplivanserin". The price was way too good to be true, but I bit the bullet and bought the compounds. So i had a friend of a friend anaylse the compound.

supposedly it's not ritanserin/ eplivanserin. I have a hard time actually getting a hold of the chemist who did the NMR test so that she could explain the result to me.

Essentially her friend who is the one im kind of talking to her through, said that the result indicated a 97% purity but that it was not the chemical in question. He said they also did a search of related compounds in the -anserin category and did not get a hit.

I was just wondering, how exactly can a person find out what the chemical is from NMR result alone? is that possible at all??

I yet again had a contact thru another chemist, again only through another friend and not directly, and their relationship is not that great, his short answer was that if it's not the chemical in question then that is that. But I really want to find out what exactly this company sent me. It's just really getting under my nerves..

Btw.. I am sorry if im posting in the wrong area or being really ignorant. I don't have a really good background in chemistry and am not a professional (obviously). If you want to school me on how it works i'd be glad to hear recommendations.

[discodermolide]

Usually you have other data, for example, a mass spectrum. But, yes by doing the appropriate NMR experiments it is possible to elucidate the structure. Of course the best method is to obtain a single crystal and get an x-ray diffraction to give you the structure.

[fotia]

Thanks so much for the reply discodermolide. I will take this into consideration.

I was wondering if anyone could take a look at the actual NMR results and let me know if they have any ideas.
They are attached to this post.
Thanks a lot. Could really use the extra opinions.

[kriggy]

Maybe you can ask your friend to run IR? Might be helpful or at least add additional information. Maybe if you could deliver the spectra someone here might be able to help you. But the the more information you gave, the better answer you get( ie C-NMR, H-NMR, IR, MS...)

Well how exactly does it work..
you might read this http://en.wikipedia.org/wiki/Nuclear_magnetic_resonance_spectroscopy

Anyway, determining the exact structure of compound solely by NMR is possible but it takes time and experience. I´ve never done it but I dont think its easy just from my experience of interpreting spectra of one of compounds I made in a lab - about 13 different carbon atoms, took me and my advisor about 2 hours and 5 different NMR experiments ¹H-NMR, ¹³C-NMR, HMQC, COSY, HMBC and we knew the structure we just wanted to asign the peaks to their coreresponding atoms)
Saying if the compound analyzed is the one you want or not is sometimes not that difficult - maybe more/less peaks in spectrum than expected is the easienst way to answer this YES/NO question.

EDIT: I think the eplivanserin spectra is missing one peak in aromatic region and I also think that the NMR is missing some peaks entirely (I think there should b e 12) and the other one has one more.