isomer


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Related to isomer: Nuclear isomer, optical isomer, geometric isomer, Cis isomer

i·so·mer

 (ī′sə-mər)
n.
1. Chemistry Any of two or more substances that have the same molecular formula but differ in the way their atoms are connected to each other, in the spatial orientation of their atoms, or, in the case of large molecules such as DNA, in their molecular topology.
2. Physics Any of two or more nuclei with the same mass number and atomic number that have different radioactive properties and can exist in any of several energy states for a measurable period of time.

[Greek īsomerēs, having equal share : īso-, iso- + meros, part, share; see (s)mer- in Indo-European roots.]

i′so·mer′ic (-mĕr′ĭk) adj.
i′so·mer′i·cal·ly adv.

isomer

(ˈaɪsəmə)
n
1. (Elements & Compounds) chem a compound that exhibits isomerism with one or more other compounds
2. (General Physics) physics a nuclide that exhibits isomerism with one or more other nuclides
isomeric adj

i•so•mer

(ˈaɪ sə mər)

n.
a chemical compound or nuclide that displays isomerism.
[1865–70; < Swedish (1830) < Greek isomerḗs equally divided =iso- iso- + -merēs, adj. derivative of méos part, division]

i·so·mer

(ī′sə-mər)
One of two or more compounds composed of the same chemical elements in the same proportions but having a different arrangement of the atoms. Isomers differ from one another in at least one physical or chemical property. Lactose and sucrose are isomers.
ThesaurusAntonymsRelated WordsSynonymsLegend:
Noun1.isomer - a compound that exists in forms having different arrangements of atoms but the same molecular weight
chemical compound, compound - (chemistry) a substance formed by chemical union of two or more elements or ingredients in definite proportion by weight
Translations

isomer

[ˈaɪsəməʳ] Nisómero m

isomer

n (Chem) → Isomer(e) nt

isomer

[ˈaɪsəməʳ] nisomero
References in periodicals archive ?
Although the p,p' isomer of DDE is in human tissue at the highest concentration, technical DDT contains approximately 10% of the o,p isomer, and o,p-DDE can be detected if sought (4).
This isomer displays permeability comparable to native gramicidin, while the RR isomer, in which the ring normal lies almost perpendicular to this axis, is significantly less permeable than natural gramicidin.
The addition of C12 CD (cyclododecanediol isomer mixture) to polyester polyol formulations is said to improve hydrolytic stability, reduce crystallinity and improve flexibility.
However, the narcotic form of methamphetamine is an isomer compound, called D-methamphetamine, and care must be taken to differentiate between the two.
Pharmaceutical applications will lead growth as regulatory requirements and competitive advantages promote the development of new and reformulated drugs containing single isomer active ingredients.
In order to obtain a complete picture of isomer distributions in the injection molded industrial PET samples, spectroscopic measurements were correlated with DSC measurements.
5 billion), relating to (+) norcisapride, an isomer of the active metabolite of Propulsid (cisapride).
The title will cover new material including the use of enzymes for the synthesis and resolution of enantiomeric compounds as well, as their use in drug discovery; how stereochemistry impacts on decisions taken during the ADMET (absorption, distribution, metabolism, excretion, toxicity) stage of drug discovery; issues faced during the final stages of the drug development process; the impact of ICH (International Conference on Harmonisation) on the use of single isomer drugs; racemic switches; and legal perspectives looking at IP and patent issues surrounding chiral switches and marketing single enantiomer switches.
Sources of PFCs are not well characterized, but isomer patterns should enable differentiation of historical and contemporary manufacturing sources.
Dietary zeaxanthin, the 3R 3'R isomer, is the only one present in food and is the only one approved for use in dietary supplements.
The daily Xylenes (Asia Pacific) report will offer daily spot assessments of isomer grade xylene and paraxylene (PX) written by an experienced aromatics team from ICIS pricing.