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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 ?
Activity of compound 6 and 3,5-dibromo-4-hydroxyphenyl substituent sustained at a level of 9.
Current work obtained the optimal dose and the feasibility of salbutamol as a substituent of isoproterenol for inducing MI.
They cover new developments in the fundamental understanding of aromatic interactions such as substituent effects, electronic effects, and thermodynamics; the discovery and characterization of new kinds of aromatic interactions, among them anion-pi interactions, and aromatic interactions on surfaces; and emerging applications of aromatic interactions in biological sciences, catalysis, organic electronics, and materials science.
2-Methyl-and 2-phenylindole, containing a C-2 substituent, also reacts to form the corresponding alcohol (compounds 24 and 25) with a mixture of at-ropisomers, owing to the presence of the methyl and phenyl group limits free rotation about the C-C bond connecting the indole and hydroxyacetoacetate group, in good yield (see 1H and 13C NMR spectral data).
Particularly, the nature of the other substituent, site preference of the other substituent's such as Ni, Zn, Al and Mn in cobalt ferrites greatly affects the structural, electrical and magnetic properties.
Despite the increasing popularity of substituent products such as the lavendin, players operating in the market remain focused on introducing newer lavender oil products.
Nevertheless, present study showed that the cavity of bCD can bind the viologen substituent in non-aqueous medium and permits thermodynamic and kinetics study.
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.
55, 56) The introduction of the substituent R with an appropriate structure is required to attain a high chiral recognition.
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.
We consider that the orientations adopted by the substituent and the pyrogallol ring with respect to such bond is likely to determine the geometry of the final product.