Crystal structure analyses of 1-(α-hydroximinobenzyl)-5-amino-1H-pyrazoles

The crystal structures of three 1-(α-hydroximinobenzyl)-5-amino-1H-pyrazoles were determined. The oxime groups of all molecules show Z configuration. Surprisingly only one molecular structure shows an intramolecular hydrogen bond. The packings of the molecules are determined by intermolecular hydrogen bonds. The two molecules of the asymmetric unit of (1) build up parallel helical chains with opposite helicities. These chains are connected. In this way is built up a three-dimensional network. The other two structures are isostructural. The molecules form parallel chains which are not connected.