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Years ago in a project I had to remove 4-hydrazinobenzoic acid (a known human carcinogen isolated from mushrooms) to a level of < 1ppb in a drug substance.We did it but not by the method I will show here. Clearing out my desk I found some of the other attempts to solve this problem. One was the reaction with glucose, to try and form a water soluble hydrazone we didn't get this product, the scheme is shown. alt text

My tame NMR spectroscopist suggested the data indicated structure 1 in the scheme, but I don't believe it. The elemental analysis shows C13H18N207 = Mwt 314. I am in the process of converting the NMR date to PDF files, when complete I shall post them here.

Here goes with the spectra, there are 13 of them! alt text alt text alt text alt text alt text alt text alt text alt text alt text alt text alt text alt text alt text

Now you know what I know! The files should be downloadable, I think.

Has anyone any idea of a reasonable product from this reaction?

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sorry, there some troubles with arrows representation in online marvin sketch

btw, here is related paper on sugar hydrazone tautomerism for unsubstituted hydrazine http://dx.doi.org/10.1016/0008-6215(83)88077-X

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Thanks, structure (far left) it is not, it does not have the required aminal proton in the NM and the 13C shift is wrong. As I said I'll post the spectra here as son as I can get them in the correct format. – quintus Jul 11 at 7:08
I don't see any contradictions with left structure. Also its formation seems more reasonable from mechanistic point of view than structure 1. There is much information on structure of sugar hydrazones in journals and books (e.g. bit.ly/cAsyoc ) – tlp Jul 14 at 19:52
I must admit I don't agree with the suggested structure (that by the NMR expert). I think it is structure 3 in your drawing (the pentose). – quintus Jul 15 at 17:39
But I guess that coupling pattern for C6 protons (d and dd) proves hexose structure. For pentose structure these signals would have been more equal because of less rotation barrier. – tlp Jul 17 at 15:46

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