4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone or nicotine-derived nitrosamine ketone (NNK) is a tobacco-specific nitrosamine. NNK is considered to be a carcinogen. NNK induces deleterious mutations in oncogenes and tumor suppression genes by forming DNA adducts, which could be considered as tumor initiation. Meanwhile, the binding of NNK to the nicotinic acetylcholine receptor promotes tumor growth by enhancing and deregulating cell proliferation, survival, migration, and invasion, thereby creating a microenvironment for tumor growth.

m-Dinitrobenzene (1,3-DBN) is a synthetic compound used in manufacture of explosives. 1,3-DNB has been used as a camphor substitute in nitrocellulose, a compound used in explosives and propellants.1,3-DNB was manufactured during both world wars as a component in the explosive roburite. Commercially, 1,3-DNB has been used extensively as an organic intermediate for m-phenylenediamine, a chemical used in the synthesis of aramid fibers and spandex. 1,3-DNB is an industrial chemical used in organic synthesis and dyes. In medicine, 1,3-DNB was used for colorimetric determination of 17-ketosteroids.