title: 4-Hydr-oxy-3-nitro-benzaldehyde.
abstract: The hydroxyl group in each of the two independent mol-ecules of the title compound, C(7)H(5)NO(4), participates in two O-H⋯O hydrogen bonds, viz. one intra-molecular bond to the nitro group and one inter-molecular bond to the aldehyde group of the same mol-ecule in the next unit, resulting in a linear chain structure. The dihedral angle between the aromatic ring and the nitro group is 10.9 (3)° in one mol-ecule and 9.9 (2)° in the other.
authors.affiliation: Department of Chemistry, University of Malaya, 50603 Kuala Lumpur, Malaysia.
authors.forename: Mohd Razali
authors.initials: MR
authors.lastname: Rizal
authors.forename: Isha
authors.initials: I
authors.lastname: Azizul
authors.forename: Seik Weng
authors.initials: SW
authors.lastname: Ng