215523-34-5Relevant articles and documents
Controlling the Reactivity of a Metal-Hydroxo Adduct with a Hydrogen Bond
Day, Victor W.,Hessefort, Logan,Jackson, Timothy A.,Opalade, Adedamola A.
supporting information, p. 15159 - 15175 (2021/09/29)
The enzymes manganese lipoxygenase (MnLOX) and manganese superoxide dismutase (MnSOD) utilize mononuclear Mn centers to effect their catalytic reactions. In the oxidized MnIIIstate, the active site of each enzyme contains a hydroxo ligand, and X-ray crystal structures imply a hydrogen bond between this hydroxo ligand and aciscarboxylate ligand. While hydrogen bonding is a common feature of enzyme active sites, the importance of this particular hydroxo-carboxylate interaction is relatively unexplored. In this present study, we examined a pair of MnIII-hydroxo complexes that differ by a single functional group. One of these complexes, [MnIII(OH)(PaPy2N)]+, contains a naphthyridinyl moiety capable of forming an intramolecular hydrogen bond with the hydroxo ligand. The second complex, [MnIII(OH)(PaPy2Q)]+, contains a quinolinyl moiety that does not permit any intramolecular hydrogen bonding. Spectroscopic characterization of these complexes supports a common structure, but with perturbations to [MnIII(OH)(PaPy2N)]+, consistent with a hydrogen bond. Kinetic studies using a variety of substrates with activated O-H bonds, revealed that [MnIII(OH)(PaPy2N)]+is far more reactive than [MnIII(OH)(PaPy2Q)]+, with rate enhancements of 15-100-fold. A detailed analysis of the thermodynamic contributions to these reactions using DFT computations reveals that the former complex is significantly more basic. This increased basicity counteracts the more negative reduction potential of this complex, leading to a stronger O-H BDFE in the [MnII(OH2)(PaPy2N)]+product. Thus, the differences in reactivity between [MnIII(OH)(PaPy2Q)]+and [MnIII(OH)(PaPy2N)]+can be understood on the basis of thermodynamic considerations, which are strongly influenced by the ability of the latter complex to form an intramolecular hydrogen bond.
FUSED BICYCLIC HETEROCYCLE DERIVATIVES AS PESTICIDES
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Paragraph 0851-0853, (2018/11/21)
The invention relates to novel compounds of the formula (I) or (I′) in which R1, R2, R3, Aa, Ab, Ac, Ad, Ae, Q and n have the definitions given above, to the use thereof as acaricides and/or insecticides for controlling animal pests and to processes and intermediates for the preparation thereof.
A one-pot method for the synthesis of naphthyridines via modified friedl?nder reaction
Zhichkin, Pavel,Beer, Catherine M. Cillo,Rennells, W. Martin,Fairfax, David J.
, p. 379 - 382 (2007/10/03)
A one-pot method for the preparation of 1,8-naphthyridine derivatives is reported. The method involves the dimetalation of an appropriate N-2-pyridylpivalamide or tert-butylcarbamate followed by reaction with a β-dimethylamino or β-alkoxyacrolein derivative. This method is also applicable to 1,6-naphthyridines. Georg Thieme Verlag Stuttgart.