Different drugs containing a basic nitrogen atom were crystallised with 2,4-dinitrophenol to study the mode of complexation in search of an antidote to 2,4-dinitrophenol poisoning. The protonated forms of quininium, quinidinium and trazodonium form N–H···O hydrogen bonds to the deprotonated O atom of the 2,4-dinitrophenolate anion, whereas haloperidolium forms a bifurcated N–H···(O,O) hydrogen bond to the deprotonated O atom of 2,4-dinitrophenol and an O atom of the adjacent nitro group. Hydrogen-bonded chains occur in the quininium, quinidinium and haloperidolium crystal structures, whereas the trazodonium structure consists of ion pairs. These results are discussed with a view to lowering the toxicity of 2,4-dinitrophenol in the body in the case of an overdose.
We thank the National Mass Spectrometry Service Centre (University of Swansea) for mass spectrometry data and the UK National Crystallographic Service (University of Southampton) for intensity data collections.
The author(s) received no financial support for the research, authorship and/or publication of this article.