Compounds having the nitro group,
–NO2 (free valence on nitrogen), which may be attached to carbon, nitrogen (as in nitramines), or oxygen (as in nitrates), among other elements (in the absence of specification,
C-nitro compounds are usually implied).
See also: dipolar compounds
Source:
PAC, 1995, 67, 1307. 'Glossary of class names of organic compounds and reactivity intermediates based on structure (IUPAC Recommendations 1995)' on page 1351 (https://doi.org/10.1351/pac199567081307)