Related Experiment Video
Updated: Aug 10, 2026

Expression, Purification, Crystallization, and Enzyme Assays of Fumarylacetoacetate Hydrolase Domain-Containing Proteins
Published on: June 20, 2019
Reactions of C-terminal omega-amino acid residues in liquid hydrogen fluoride
M A Bednarek1, J P Springer, B R Cunningham
1Merck Research Laboratories, Rahway, New Jersey.
Abstract:
The benzyl-ester bond linking the C-terminal delta-aminovaleric acid residue of a peptide to a polymeric support was cleaved with liquid hydrogen fluoride in the presence of anisole, added as scavenger. Instead of the expected peptide with a free carboxyl group at the C-terminus, a peptide terminating in a ketone derivative was obtained. The unusual extent of this known side-reaction was attributed to the effect of the distance between the amino group and the carboxyl group in the C-terminal residue. The results of model experiments corroborated this view.
More Related Videos
09:39Targeted Antibody Blocking by a Dual-Functional Conjugate of Antigenic Peptide and Fc-III Mimetics (DCAF)
Published on: September 17, 2019
05:57Synthesizing Amino Acids Modified with Reactive Carbonyls in Silico to Assess Structural Effects Using Molecular Dynamics Simulations
Published on: April 26, 2024
Related Concept Videos
Acid Halides to Carboxylic Acids: Hydrolysis
As shown below, the mechanism involves a nucleophilic attack by water at the carbonyl carbon to form a tetrahedral intermediate. This is followed by the reformation of the carbon–oxygen π bond along with the departure of a halide ion. A final proton transfer step yields carboxylic acid...
Acid-Catalyzed α-Halogenation of Aldehydes and Ketones
In the first step of the mechanism, the acid protonates the carbonyl oxygen resulting in a resonance-stabilized cation, which subsequently loses an α-hydrogen to form an enol tautomer. The C=C bond in an enol is highly nucleophilic because of the electron-donating nature of the –OH group. Consequently, the double bond attacks an electrophilic halogen to form a...
Radical Halogenation: Thermodynamics
Radical Substitution: Hydrogenolysis of Alkyl Halides with Tributyltin Hydride
The bonds formed in this reaction are stronger than the bonds broken, making it energetically favorable. The reaction follows a radical chain mechanism similar to radical halogenation reactions,...
Carboxylic Acids to Esters: Acid-Catalyzed (Fischer) Esterification Mechanism
Hydrogen Bonds