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Updated: Jul 10, 2026

11:42
Solid Phase Synthesis of a Functionalized Bis-Peptide Using "Safety Catch" Methodology
Published on: May 15, 2012
[Benzylpenicillin interaction with amines in the organic phase]
Summary
Benzylpenicillin interacts with amines in nonaqueous solutions, with interactions depending on amine form and pH. Researchers determined interaction and dissociation constants for various amines, aiding in understanding antibiotic behavior in different phases.
Area of Science:
- Pharmacology
- Physical Chemistry
- Organic Chemistry
Context:
- Investigates the behavior of benzylpenicillin, a key antibiotic, in nonaqueous environments.
- Focuses on the complex interactions between benzylpenicillin and various amines (aromatic and aliphatic).
- Utilizes a butyl acetate solvent system to simulate nonaqueous conditions.
Purpose:
- To elucidate the pH-dependent distribution of benzylpenicillin in a nonaqueous-amine-water system.
- To describe a model for benzylpenicillin-amine interactions, including amine dissociation equilibrium.
- To quantify the interaction and dissociation constants for different amines.
Summary:
- Benzylpenicillin's distribution coefficient was measured across a pH gradient in an amine-butyl acetate-water system.
- A model was developed to explain the interactions between benzylpenicillin and both molecular and cationic forms of amines.
- Experimental data allowed for the calculation of specific interaction and dissociation constants for a range of amines.
Impact:
- Provides crucial data for understanding benzylpenicillin's behavior and stability in nonaqueous formulations.
- Contributes to the rational design of drug delivery systems involving antibiotics and amines.
- Enhances knowledge of acid-base interactions in organic solutions relevant to pharmaceutical science.
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