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Recording Gamma Band Oscillations in Pedunculopontine Nucleus Neurons
Published on: September 14, 2016
2-Amino-4-methyl-pyridinium 6-carb-oxy-pyridine-2-carboxyl-ate sesquihydrate
Abstract:
In the title compound, C(6)H(9)N(2) (+)·C(7)H(4)NO(4) (-)·1.5H(2)O, extensive O-H⋯O, O-H⋯N, N-H⋯O and C-H⋯O hydrogen bonds, as well as ion pairing, π-π stacking inter-actions [centroid-centroid distances = 3.4690 (8) and 3.6932 (8) Å between aromatic rings] occur in the crystal. There are hydrogen-bonding inter-actions between water mol-ecules, which result in cyclic tetra-meric water clusters. One of the water O molecules has half occupancy. In the anion molecules, the -CO(2) and -CO(2)H groups make torsion angles of 1.73 (18) and -12.14 (18)° with respect to the ring.
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Nomenclature of Carboxylic Acid Derivatives: Amides and Nitriles
The IUPAC and common names of amides are derived from the parent carboxylic acid, by replacing the suffix “oic acid” and “ic acid,” respectively, with “amide.” In the following example, the IUPAC name ethanamide is derived from ethanoic acid, and the common name, acetamide, is obtained from acetic acid.
Structures of Carboxylic Acid Derivatives
Carboxylic acid derivatives contain an acyl group attached to a heteroatom such as chlorine, oxygen, or nitrogen. The carbonyl carbon and oxygen are both sp2-hybridized with an unhybridized p orbital.
The three sp2 orbitals of the carbonyl carbon form three σ bonds, one each with the carbonyl oxygen, the α carbon, and the heteroatom, whereas the other two sp2 orbitals of the carbonyl oxygen are occupied by the lone pairs. Further, the unhybridized p...
Structure of Amines

