Related Experiment Video
Updated: Aug 20, 2026

Synthesis of pH Dependent Pyrazole, Imidazole, and Isoindolone Dipyrrinone Fluorophores using a Claisen-Schmidt Condensation Approach
Published on: June 10, 2021
Synthesis and analgesic action of N-(substituted-ethyl)pyrrole-3,4-dicarboximides
W Malinka1, M Kaczmarz, A Redzicka
1Department of Chemistry of Drugs, Wrocław Medical University, ul. Tamka 1, 50-137 Wrocław, Poland. malinka@bf.uni.wroc.pl
Abstract:
We prepared a series of new N-[2-(4-substitutedpiperazin-1-yl)ethyl]-1-(n-butyl or phenyl)-2,5-dimethyl-3,4-pyrroledicarboximides 3 and the related products 4 and 5, nine representatives of which were evaluated as potential analgesic agents in an animal model (mice). The new pyrroledicarboximides were not toxic (LD50 > or = 1466 mg/kg) and eight of them displayed analgesic activity approximately 1.5-5 times superior to that of ASA in the writhing test. However, the compounds were found to be unstable in methanol solution and in dilute bases (methanol/NaOMe). The S-A relationship is discussed.
Related Concept Videos
Opioid Analgesics: Synthetic and Semisynthetic Opioids
Analgesia and Pain Management
Basicity of Heterocyclic Aromatic Amines
Preparation of Amides
The DCC-promoted synthesis of amides begins with the protonation of DCC by carboxylic acid. The protonation makes it a better acceptor. Next, the addition of carboxylate to the protonated carbodiimide gives a reactive acylating agent.
Subsequently, the amine acts as a nucleophile that attacks the acylating agent to form a tetrahedral intermediate. In the...
Adrenergic Agonists: Chemistry and Structure-Activity Relationship
Aromatic ring substitutions: Substituting the aromatic ring with –OH groups at positions 3 and 4 yields catecholamines (e.g., epinephrine), which have a high affinity for adrenoceptors. Hydrogen bonding between –OH groups and receptors enhances adrenergic activity.
Separation of the aromatic...
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.

