Jove
Visualize
Contact Us
JoVE
x logofacebook logolinkedin logoyoutube logo
ABOUT JoVE
OverviewLeadershipBlogJoVE Help Center
AUTHORS
Publishing ProcessEditorial BoardScope & PoliciesPeer ReviewFAQSubmit
LIBRARIANS
TestimonialsSubscriptionsAccessResourcesLibrary Advisory BoardFAQ
RESEARCH
JoVE JournalMethods CollectionsJoVE Encyclopedia of ExperimentsArchive
EDUCATION
JoVE CoreJoVE BusinessJoVE Science EducationJoVE Lab ManualFaculty Resource CenterFaculty Site
Terms & Conditions of Use
Privacy Policy
Policies

Related Concept Videos

Extraction: Advanced Methods00:56

Extraction: Advanced Methods

402
Metal ions can be separated from one another by complexation with organic ligands–the chelating agent– to form uncharged chelates. Here, the chelating agent must contain hydrophobic groups and behave as a weak acid, losing a proton to bind with the metal. Since most organic ligands used in this process are insoluble or undergo oxidation in the aqueous phase, the chelating agent is initially added to the organic phase and extracted into the aqueous phase. The metal-ligand complex is...
402
Preparation of Alcohols via Substitution Reactions01:38

Preparation of Alcohols via Substitution Reactions

5.7K
Overview
Alcohols can be synthesized from alkyl halides via nucleophilic substitution reactions. The highly polar carbon-halogen bond in the substrate makes halide a good leaving group.  The hydroxide ion or water can act as a nucleophile to take the place of halide and form an alcohol. The substitution reactions occur via two different reaction pathways, SN1 or SN2,  depending on the nature of carbon attached to the halide.
Primary alcohols are synthesized from primary alkyl halides, and the...
5.7K
Phase II Reactions: Miscellaneous Conjugation Reactions01:19

Phase II Reactions: Miscellaneous Conjugation Reactions

35
Phase II biotransformations are detoxification mechanisms that conjugate xenobiotics with endogenous substances, neutralizing their toxicity.
A key example involves the conjugation of cyanide ions, which impair cellular respiration and alter hemoglobin into non-oxygen-carrying cyanmethemoglobin. To neutralize this threat, a sulfur atom from thiosulphate is transferred to the cyanide ion, catalyzed by the enzyme rhodanese, resulting in an inactive compound called thiocyanate. The production of...
35
Acid Halides to Ketones: Gilman Reagent01:14

Acid Halides to Ketones: Gilman Reagent

2.7K
Lithium dialkyl cuprate, also known as Gilman reagents, selectively reduces acid halides to ketones. The acid chloride is treated with Gilman reagent at −78 °C in the presence of ether solution to produce a ketone in good yield.
As shown below, the mechanism proceeds in two steps. First, one of the alkyl groups of the reagent acts as a nucleophile and attacks the acyl carbon of the acid chloride to form a tetrahedral intermediate. This is followed by the reformation of the carbon–oxygen...
2.7K
Diels–Alder Reaction: Characteristics of Dienophiles01:24

Diels–Alder Reaction: Characteristics of Dienophiles

5.9K
In a Diels–Alder reaction, the diene is usually an electron-rich system and acts as a nucleophile, whereas the dienophile is electron-deficient and functions as an electrophile. Much like the diene, the nature of the dienophile significantly impacts the outcome of the reaction. 
Characteristics of Dienophiles
Generally, the best dienophiles are alkenes containing electron-withdrawing substituents such as carbonyl, nitrile, and nitro groups. The feasibility of a Diels–Alder reaction depends...
5.9K
Oxidation of Phenols to Quinones01:17

Oxidation of Phenols to Quinones

2.8K
In the presence of oxidizing agents, phenols are oxidized to quinones. Quinones can be easily reduced back to phenols using mild reducing agents. The electron-donating hydroxyl group enhances the reactivity of the aromatic ring, enabling oxidation of the ring even in the absence of an α hydrogen.
o-hydroxy phenols are oxidized to o-quinones and p-hydroxy phenols to p-quinones. Such redox reactions involve the transfer of two electrons and two protons. The reversible redox...
2.8K

You might also read

Related Articles

Articles linked to this work by shared authors, journal, and citation graph.

Sort by
Same author

Structural insights into <i>ortho</i>-aminophenol oxidases: kinetic and crystallographic characterization of <i>Sm</i>NspF and <i>Sg</i>GriF.

Inorganic chemistry frontiers·2026
Same author

Polyoxometalates in environmental remediation and energy storage.

Environmental science. Nano·2026
Same author

More Than a Buffer in Biochemistry: Tris as an Architect and Gatekeeper of Metal-Oxo Assembly.

Angewandte Chemie (International ed. in English)·2026
Same author

Towards synthetic catechol rich protein analogues through tyrosinase catalyzed activation of a tyrosine dipeptide in continuous mode.

Catalysis science & technology·2025
Same author

Speciation atlas of polyoxometalates in aqueous solution (Part II): Molybdenum browns.

Science advances·2025
Same author

Data-Driven Polyoxometalate Chemistry.

Chemistry (Weinheim an der Bergstrasse, Germany)·2025

Related Experiment Video

Updated: May 27, 2025

[DPEPhosbcpCu]PF6: A General and Broadly Applicable Copper-Based Photoredox Catalyst
09:12

[DPEPhosbcpCu]PF6: A General and Broadly Applicable Copper-Based Photoredox Catalyst

Published on: May 21, 2019

9.2K

Beyond Phenolics: Alternative Substrates for Type III Copper Enzymes.

Matthias Pretzler1, Annette Rompel1

  • 1Universität Wien, Fakultät für Chemie, Institut für Biophysikalische Chemie, Josef-Holaubek-Platz 2, 1090, Wien, Austria.

Chembiochem : a European Journal of Chemical Biology
|February 18, 2025
PubMed
Summary

Tyrosinases (TYRs) are copper enzymes that typically process phenols. This study highlights their overlooked activity on aromatic amines, expanding their biotechnological applications.

Keywords:
Alternative substrateAromatic aminesMethoxyphenolsType III copper enzymesTyrosinases

More Related Videos

Ion Mobility-Mass Spectrometry Techniques for Determining the Structure and Mechanisms of Metal Ion Recognition and Redox Activity of Metal Binding Oligopeptides
11:04

Ion Mobility-Mass Spectrometry Techniques for Determining the Structure and Mechanisms of Metal Ion Recognition and Redox Activity of Metal Binding Oligopeptides

Published on: September 7, 2019

9.1K
Generation of Scalable, Metallic High-Aspect Ratio Nanocomposites in a Biological Liquid Medium
13:34

Generation of Scalable, Metallic High-Aspect Ratio Nanocomposites in a Biological Liquid Medium

Published on: July 8, 2015

9.0K

Related Experiment Videos

Last Updated: May 27, 2025

[DPEPhosbcpCu]PF6: A General and Broadly Applicable Copper-Based Photoredox Catalyst
09:12

[DPEPhosbcpCu]PF6: A General and Broadly Applicable Copper-Based Photoredox Catalyst

Published on: May 21, 2019

9.2K
Ion Mobility-Mass Spectrometry Techniques for Determining the Structure and Mechanisms of Metal Ion Recognition and Redox Activity of Metal Binding Oligopeptides
11:04

Ion Mobility-Mass Spectrometry Techniques for Determining the Structure and Mechanisms of Metal Ion Recognition and Redox Activity of Metal Binding Oligopeptides

Published on: September 7, 2019

9.1K
Generation of Scalable, Metallic High-Aspect Ratio Nanocomposites in a Biological Liquid Medium
13:34

Generation of Scalable, Metallic High-Aspect Ratio Nanocomposites in a Biological Liquid Medium

Published on: July 8, 2015

9.0K

Area of Science:

  • Biochemistry
  • Enzymology

Background:

  • Tyrosinases (TYRs) are type III copper enzymes crucial for melanin production.
  • TYRs catalyze the oxidation of phenols and catechols using copper cofactors and molecular oxygen.

Purpose of the Study:

  • To review and consolidate data on the activity of tyrosinases on non-phenolic substrates, specifically aromatic amines.
  • To highlight the potential of TYRs in oxidizing aminophenols and anilines.

Main Methods:

  • Literature review and data synthesis on tyrosinase activity.
  • Analysis of existing studies reporting tyrosinase reactions with aromatic amines.

Main Results:

  • Tyrosinases demonstrate significant activity on aromatic amines, a function often overlooked.
  • This activity extends the range of substrates amenable to TYR-catalyzed oxidation beyond phenols.

Conclusions:

  • The reactivity of tyrosinases on aromatic amines broadens their utility in biotechnology, enabling production of N-phenyl imines and phenoxazinone derivatives.
  • Tyrosinases should be considered for metabolic engineering involving the oxidative modification of aromatic amines.