Novel features of the 1,3 rearrangement of S-(–)-N-(1-phenylethyl)diphenylvinylideneamine to S-(–)-2,2,3-triphenylbutyronitrile

Singer, Lawrence A.; Lee, Kyu Wang

doi:10.1039/c39740000962

Cited by 45 publications

(42 citation statements)

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“…The selectivity of affinity labeling is based on the binding specificity of the enzyme [38]. The use of enzyme-activated inhibitors takes advantage both of the binding and the kinetic specificity of the target enzyme [39,40].…”

Section: Comparison With Other Types Of Active-site-directed Chemicalmentioning

confidence: 99%

Specific Irreversible Inhibition of Enzymes Concomitant to the Oxidation of Carbanionic Enzyme · Substrate Intermediates by Hexacyanoferrate(III)

Christen

Cogoli-Greuter

Healy

et al. 1976

European Journal of Biochemistry

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Four different enzymes, class I fructose-l,6-bisphosphate aldolase from rabbit muscle, class I1 fructose-l,6-bisphosphate aldolase from yeast, transaldolase, and transketolase, are inactivated progressively in the presence of their specific substrates and hexacyanoferrate(II1). The inactivation is strictly linked to the oxidation of the carbanionic enzyme . substrate intermediates of these enzymes reported previously [Healy, M. J. and Christen, P. (1973) Biochemistry, 12, 351. However, the loss of activity is not due to the products of this oxidation, i.e. to hexacyanoferrate(II), or to the oxidation product of the substrate such as hydroxypyruvaldehyde phosphate in the case of aldolase The rate of inactivation is independent of the concentration of the enzyme, suggesting that the inactivation results from an intramolecular reaction, i.e. the inactivating agent produced by oxidation of the enzyme . substrate intermediate is not released from the active site but rather reacts in situ with the enzyme protein. Accordingly, addition of fructose 1,6-bisphosphate to a mixture of aldolase and transaldolase (or transketolase) with hexacyanoferrate(II1) initiates the exclusive inactivation of aldolase while the addition of fructose 6-phosphate induces the exclusive inactivation of transaldolase (or transketolase respectively).The combination of natural substrate with hexacyanoferrate(II1) thus constitutes a binary system for the chemical modification of enzymes that form oxidizable carbanionic intermediates. The modification by oxidative activation of enzyme . substrate intermediates is (a) highly specific for a given enzyme (the degree of specificity is determined by the binding and kinetic specificity of the enzyme for its natural substrate) and (b) results in a modification of groups at or near the enzyme's active site (reaction of the oxidatively activated substrate in situ).

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Section: Comparison With Other Types Of Active-site-directed Chemicalmentioning

confidence: 99%

Specific Irreversible Inhibition of Enzymes Concomitant to the Oxidation of Carbanionic Enzyme · Substrate Intermediates by Hexacyanoferrate(III)

Christen

Cogoli-Greuter

Healy

et al. 1976

European Journal of Biochemistry

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“…However, ketenimine 13 c is stable under the reaction conditions (55 8C, CuCl) in the absence of precursor 12 a; only at elevated temperatures (125 8C) 13 c does decompose into isobutene and diphenylacetonitrile. [26] A more likely source is an intermediate iminium ion as quaternary tert-butyl-ammonium ions release isobutene even at room temperature.…”

Section: Resultsmentioning

confidence: 99%

Methylene‐Azaphosphirane as a Reactive Intermediate

Slootweg

Vlaar

Vugts

et al. 2005

Chemistry A European J

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Reaction of the transient phosphinidene complexes R‐PW(CO)5 with N‐substituted‐diphenylketenimines leads unexpectedly to the novel 2‐aminophosphindoles, as confirmed by an X‐ray crystal structure determined for one of the derivatives. Experimental evidence for a methylene‐azaphosphirane intermediate was found by using the iron‐complexed phosphinidene iPr2N‐PFe(CO)4, which affords the 2‐aminophosphindole together with the novel methylene‐2,3‐dihydro‐1H‐benzo[1,3]azaphosphole. Analysis of the reaction pathways with DFT indicates that the initially formed methylene‐azaphosphirane yields both phosphorus heterocycles by way of a [1,5]‐ or [1,3]‐sigmatropic shift, respectively, followed by a H‐shift. Strain underlies both rearrangements, which causes these remarkably selective conversions that can be tuned by changing the substituents.

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Section: Resultsmentioning

confidence: 99%