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Updated: May 27, 2026

Preparation and In Vivo Use of an Activity-based Probe for N-acylethanolamine Acid Amidase
Published on: November 23, 2016
2-(5-Cyclo-hexyl-3-methyl-sulfanyl-1-benzofuran-2-yl)acetic acid
Abstract:
In the title compound, C(17)H(20)O(3)S, the cyclo-hexyl ring adopts a chair conformation. In the crystal, the carboxyl groups are involved in inter-molecular O-H⋯O hydrogen bonds, which link the mol-ecules into centrosymmetric dimers. These dimers are further stabilized by weak inter-molecular C-H⋯O hydrogen bonds. In addition, the crystal structure also exhibits aromatic π-π inter-actions between the furan rings of adjacent mol-ecules [centroid-centroid distance = 3.505 (2) Å, inter-planar distance = 3.385 (2) Å and slippage = 0.909 (2) Å], and inter-molecular C-H⋯π inter-actions.
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Nomenclature of Carboxylic Acid Derivatives: Acid Halides, Esters, and Acid Anhydrides
The IUPAC and common names of acid halides are derived from the corresponding carboxylic acids, by changing “ic acid” to “yl halide.” For example, as shown below, the IUPAC name ethanoyl chloride is derived from ethanoic acid, and the common name, acetyl chloride, is obtained from acetic acid.
IUPAC Nomenclature of Carboxylic Acids
For acyclic saturated monocarboxylic acids, the longest hydrocarbon chain containing the –COOH carbon is identified as the parent chain. Then, the last -e of the parent hydrocarbon name is replaced with a suffix -oic acid.
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.
IUPAC Nomenclature of Aldehydes
Electrophilic Aromatic Substitution: Friedel–Crafts Acylation of Benzene
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...

