Different weak interactions in the crystals of three isomeric (E)-N-methyl-N′-(nitrobenzylidene)-2-(thiophen-2-yl)acetohydrazides

The crystal structures of three isomeric (E)-N-methyl-N′-(nitrobenzylidene)-2-(thiophen-2-yl)acetohydrazides (formula C14H13N3O3S) are described, with the nitro group in ortho, meta and para positions in the benzene ring. In each crystal structure, molecules are linked by various weak interactions (C—H...O and C—H...π bonds, and π–π stacking), leading to three-dimensional networks in each case, but with little similarity between them.