X-ray diffraction analysis of the structure of 3-nicotinehydroxamic acid and pyrazinecarbohydroxamic acid monohydrate

X-ray diffraction analysis of the crystal structure of 3-nicotine- and pyra zinecarbohydroxamic acids revealed that the molecules were present in keto tautomeric form and possessed Z-configuration. The system of the intermolec ular hydrogen bonds is the most affected by the character or the aromatic s ubstituent and the presence of crystallization water molecules in the struc ture.