Aminopyridine oxides, tautomerism

This method is not applicable if the spectra of the potentially tautomeric compound and both alkylated derivatives are very similar, e.g., it is not suited to an investigation of the tautomerism of 4-aminopyridine 1-oxide (Fig. 3). A further limitation is that often only qualitative conclusions can be drawn because no contribution from the spectrum of the minor constituent can be found in the spectrum of the tautomeric compound. It should also be noted that, un-... 

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