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An atom or group substituted for another in a chemical compound.
Of or relating to such an atom or group.

[Latin substituēns, substituent-, present participle of substituere, to substitute; see substitute.]


(Chemistry) chem an atom or group that replaces another atom or group in a molecule or can be regarded as replacing an atom in a parent compound
substituted or substitutable
[C19: from Latin substituere to substitute]


(sʌbˈstɪtʃ u ənt)

an atom or atomic group that takes the place of another atom or group present in the molecule of the original compound.
[1890–95; < Latin substituent-, s. of substituēns, present participle of substituere to substitute; see -ent]
References in periodicals archive ?
IMZ-O presents two main differences with respect to IMZ-B, including the counterion, bromide, in place of tetrafluoroborate, and the long alkyl chain substituent of the nitrogen atom in position 1 that could give easier solubility in the rubber matrix.
PMMA, PTFEMA, PPhMA, and PPFPhMA showed four types of birefringence properties, even though they were all methacrylates and their molecular structures only differed in terms of the substituent R in the side chains, as shown in Fig.
The Pentafluoroethyl group has been advanced as the "New Substituent of the Future" for bioactive compound development by Catylix.
Teknologian Tutkimuskeskus VTT has been granted a patent for particles of a polysaccharide derivative, having at least one substituent with conjugated unsaturated bonds and exhibiting an index of refraction in excess of 1.
Topics covered include ring synthesis, substituent installation and modification, reduction to partially hydrogenated pyridines, piperidines, and quinolines, alkaloid synthesis, fluorination, and the use of pyridines as reagents.
Les dispositions de l'article 39 de la loi de finances complementaire pour 2009 substituent l'extrait de role apure par l'attestation de situation fiscale.
They differ in the orientation of their fluorine substituent at C3 and whether they contain an amine or a guanidine functional group at C4.
82 while literature reported values for the compounds with a methyl or decyl substituent at the meso position are 0.
and methylene protons, respectively: and [DELTA][zeta] is the protonational chemical shift increase of the substituent groups.
His first, titled “Ortho Effect in Electron Ionization Mass Spectrometry of N-Acylanilines Bearing a Proximal Halo Substituent,” appeared in the Journal of the American Mass Spectrometry Society in 2008.