Crystal structure and Hirshfeld surface analysis of 1-[2-(2-chloro-eth-oxy)eth-yl]-2-methyl-4-nitro-1-imidazole.

Imidazoles are a widely studied class of heterocyclic compounds with significant biological and pharmacological relevance, including applications as fungicides, herbicides, and therapeutic agents. The title compound, CHClNO (), is a structural analogue and impurity of the anti-protozoal drug metronidazole, making it valuable for mechanistic and drug development studies. Here, we report its crystal structure and Hirshfeld surface analysis. Crystals of are triclinic, space-group type 1, with two independent mol-ecules ( and ) in the asymmetric unit, each exhibiting chloro-eth-oxy-ethyl chain disorder over two conformations. Both mol-ecules have essentially planar methyl-nitro-1-imidazole cores, with conformational variation arising from the side chains. The structure lacks conventional hydrogen bonds but features several weak C-H⋯O, C-H⋯N, and C-H⋯Cl inter-actions, connecting mol-ecules into dimers and layers parallel to the -plane. Hirshfeld surface analysis reveals that the mol-ecular environments of and are similar and dominated by contacts involving hydrogen.