Protonation of Polymethylphenols
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چکیده
منابع مشابه
Asymmetric protonation of EmrE.
The small multidrug resistance transporter EmrE is a homodimer that uses energy provided by the proton motive force to drive the efflux of drug substrates. The pKa values of its "active-site" residues--glutamate 14 (Glu14) from each subunit--must be poised around physiological pH values to efficiently couple proton import to drug export in vivo. To assess the protonation of EmrE, pH titrations ...
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Enantioselective protonation is a common process in biosynthetic sequences. The decarboxylase and esterase enzymes that effect this valuable transformation are able to control both the steric environment around the proton acceptor (typically an enolate) and the proton donor (typically a thiol). Recently, several chemical methods to achieve enantioselective protonation have been developed by exp...
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The addition of nucleophiles to electron-deficient alkenes represents one of the more general and commonly used strategies for the convergent assembly of more complex structures from simple precursors. In this review the addition of diverse protic and organometallic nucleophiles to electron-deficient alkenes followed by enantioselective protonation is summarized. Reactions are first categorized...
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Light changes the structure of chloroplasts. This effect was investigated by high resolution electron microscopy, photometric methods, and chemical modification. (a) A reversible contraction of chloroplast membrane occurs upon illumination, dark titration with H(+), or increasing osmolarity. These gross structural changes arise from a flattening of the thylakoids, with a corresponding decrease ...
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ژورنال
عنوان ژورنال: Canadian Journal of Chemistry
سال: 1974
ISSN: 0008-4042,1480-3291
DOI: 10.1139/v74-489