Related Experiment Video
Updated: Feb 10, 2026

Synthesis of pH Dependent Pyrazole, Imidazole, and Isoindolone Dipyrrinone Fluorophores using a Claisen-Schmidt Condensation Approach
Published on: June 10, 2021
An efficient biocatalytic synthesis of imidazole-4-acetic acid
Weirui Zhao1, Huanru Ding1,2, Sheng Hu1
1School of Biological and Chemical Engineering, Ningbo Institute of Technology, Zhejiang University, No. 1, Xue Fu Road, Yin Zhou District, Ningbo, Zhejiang, China.
Objective:
To develop a new and efficient biocatalytic synthesis method of imidazole-4-acetic acid (IAA) from L-histidine (L-His).
Results:
L-His was converted to imidazole-4-pyruvic acid (IPA) by an Escherichia coli whole-cell biocatalyst expressing membrane-bound L-amino acid deaminase (mL-AAD) from Proteus vulgaris firstly. The obtained IPA was subsequently decarboxylated to IAA under the action of H2O2. Under optimum conditions, 34.97 mM IAA can be produced from 50 mM L-His, with a yield of 69.9%.
Conclusions:
Compared to the traditional chemical synthesis, this biocatalytic method for IAA production is not only environmentally friendly, but also more cost effective, thus being promising for industrial IAA production.
Related Concept Videos
Acid Halides to Alcohols: LiAlH4 Reduction
The mechanism proceeds in three steps. First, the nucleophilic hydride ion attacks the carbonyl carbon of the acid halide to form a tetrahedral intermediate. Next, the carbonyl group is re-formed, and the halide ion departs as a leaving group, generating an aldehyde. A second nucleophilic attack by the hydride yields an alkoxide ion, which, upon protonation, gives a primary alcohol as...
Synthesis and Decomposition Reactions
Weak Acid Solutions
Ions as Acids and Bases
Salts are ionic compounds composed of cations and anions, either of which may be capable of undergoing an acid or base ionization reaction with water. Aqueous salt solutions, therefore, may be acidic, basic, or neutral, depending on the relative acid-base strengths of the salt’s constituent ions. For example, dissolving the ammonium chloride in water results in its dissociation, as described by the equation:
Acetals and Thioacetals as Protecting Groups for Aldehydes and Ketones
In the presence of multiple functional groups, when selective reduction of one group over the other is desired, groups like aldehydes and ketones that form acetals...
Amino acids

