Nitric oxide synthases activation and inhibition by metallacarborane-cluster-based isoform-specific affectors

Robert Kaplánek1, Pavel Martásek, Bohumír Grüner

  • 1Department of Analytical Chemistry, Institute of Chemical Technology in Prague, Technická 5, 166 28 Prague 6, Czech Republic.

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Isomerism in Complexes
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All meta-directing substituents are deactivating groups. These substituents withdraw electrons from the aromatic ring, making the ring less reactive toward electrophilic substitution. For example, the nitration of nitrobenzene is 100,000 times slower than that of benzene because of the deactivating effect of the nitro group. The first step in an electrophilic aromatic substitution is the addition of an electrophile to form a resonance-stabilized carbocation. The energy diagrams for the...
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