TAUTOMER

tôˈtəmər, one of two or more structural isomers that exist in equilibrium and are readily converted from one isomeric form to another. Of the various types of tautomerism that are possible, two are commonly observed. In keto-enol tautomerism a simultaneous shift of electrons and a hydrogen atom occurs; it was first observed by K. Meyer in the ethyl ester of 3-oxobutanoic acid (ethyl acetoacetate), which occurs naturally as a mixture of the two forms. Ring-chain tautomerism, first recognized by Emil Fischer, is exhibited by glucose. It arises as a result of the aldehyde group (-CHO) in a sugar chain molecule reacting with one of the hydroxy groups (-OH) in the same molecule to give it a cyclic (ring-shaped) form.

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The Columbia Encyclopedia, Sixth Edition Copyright© 2004, Columbia University Press. Licensed from Lernout & Hauspie Speech Products N.V. All rights reserved.

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Questia Books and Articles on: Tautomer
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books on: Tautomer  - 5 results

 
 
1.
Style Guide for Chemists
Book by Louis F. Fieser, Mary Fieser; Reinhold, 1960
Subjects: Chemistry--Terminology, Technical Writing
...The keto compound is the more stable tautomer and is the exclusive product of either...The keto compound is the more stable tautomer; hence either of the two preparative reactions results in the formation of this tautomer." 6.2. Undesirable emphasis. Repetition...
2.
Chambers's Technical Dictionary
Book by C. F. Tweney, L. E. C. Hughes; Macmillan, 1958
Subjects: Technology--Dictionaries
...marine types, but not necessarily closely related to them. pseudomerism Chem. . A form of tautomerism in which only one tautomer is known, although derivatives corresponding to both forms can be prepared. pseudometamerism Zool. . The condition of repetition...
3.
Agents of Bioterrorism: Pathogens and Their Weaponization
Book by Geoffrey Zubay; Columbia University Press, 2005
Subjects: Biological Weapons, Pathogenic Microorganisms
...protein has a unique molecular weight and isoelectric point. Tachycardia Unusually high heart rate. Tachypnea Rapid breathing. Tautomer Compound related to another molecule by the chemical process of tau- tomerization. T cells (lymphocytes) Immune cells de...
4.
Hydrogen Ion Concentration: Its Significance in the Biological Sciences and Methods for Its Determinations - Vol. 1
Book by Leonor Michaelis, William A. Perlzweig; Williams & Wilkins Company, 1926
Subjects: Biochemistry, Hydrogen-Ion Concentration
...constitution shown in I below. This form is tautomeric with the form shown in II. I II The form I is colorless, while the tautomer II because of its quinonoid double bond is colored, and because of its carboxyl group strongly acidic. The latter form cannot...
5.
The American Intellectual Tradition - Vol. 2
Book by David A. Hollinger, Charles Capper; Oxford University Press, 2006
Subjects: United States--Intellectual Life--Sources
...lecture gives this example ofwhat he means. Chemists have long wrangled over the inner constitution of certain bodies called tautomer- ous. Their properties seemed equally consistent with the notion that an instable hydrogen atom oscillates inside of them...


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journal articles on: Tautomer  - 2 results

 
 
1.
Stimulus Control and Drug Dependence
Journal article by R.J. Degrandpre, Warren K. Bickel; The Psychological Record, Vol. 43, 1993
Subjects: Conditioned response--Usage, Drug abuse--Care and treatment
...stimuli with D1 or D2 as comparison stimuli (B|tautomer~D). Comparison selections were made under extinction...relations between two exteroceptive stimuli (B|tautomer~C, B|tautomer~D) and also between interoceptive and exteroceptive...
2.
Learning in Sequential Auctions
Journal article by Thomas D. Jeitschko; Southern Economic Journal, Vol. 65, 1998
Subjects: Auctions--Economic aspects, Information theory in economics--Research
...strategy F.sub.2. Specifically, (1 - b)(1 - Rho.sub.L + Rho.sub.L)F.sub.2(b) = (1 - Rho.sub.L) tautomer F.sub.2(b) = b/(1 - b)(1 - Rho.sub.L)/Rho.sub.L. Clearly, a bidder cannot improve by placing a bid...


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encyclopedia articles on: Tautomer  - 2 results

 
 
1.
Tautomer
Encyclopedia article; The Columbia Encyclopedia, Sixth Edition, 2009
TAUTOMER to t m r, one of two or more structural isomers that exist in equilibrium and are readily converted from one isomeric form to...
2.
Fluxional Molecules
Encyclopedia article; The Columbia Encyclopedia, Sixth Edition, 2009
...rapid intramolecular rearrangements among their component atoms. As in structural isomerism and tautomerism (see isomer ; tautomer ), fluxional compounds maintain the same number of component atoms. At equilibrium, fluxional molecules may manifest many...


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