Related Experiment Video

Updated: Jun 18, 2026

Functionalized Spirocyclic Heterocycle Synthesis and Cytotoxicity Assay
05:17

Functionalized Spirocyclic Heterocycle Synthesis and Cytotoxicity Assay

Published on: February 9, 2021

Total synthesis and cytotoxicity evaluation of all ochratoxin A stereoisomers

Benedikt Cramer1, Henning Harrer, Kazuhiko Nakamura

  • 1Institut für Lebensmittelchemie, Westfälische Wilhelms-Universität Münster, Corrensstrasse 45, 48149 Münster, Germany. cramerb@uni-muenster.de

Bioorganic & Medicinal Chemistry
|November 19, 2009
PubMed

Insights

The mycotoxin ochratoxin A

Area of Science:

  • Toxicology
  • Biochemistry
  • Organic Chemistry

Background:

  • Mycotoxin ochratoxin A is a potent inhibitor of protein biosynthesis.
  • It exhibits cytotoxicity at nanomolar concentrations.
  • Understanding stereochemistry's role in ochratoxin A's toxicity is crucial.

Purpose of the Study:

  • To investigate the relationship between stereochemistry and cytotoxicity of ochratoxin A.
  • To synthesize all four stereoisomers of ochratoxin A.
  • To evaluate the cytotoxic and apoptotic potential of each stereoisomer.

Main Methods:

  • Synthesis of all four ochratoxin A stereoisomers.
  • Cytotoxicity and apoptosis assays using the Hep G2 liver cell line.
  • Comparative analysis of the biological activity of different stereoisomers.

Main Results:

  • The l-configuration of the phenylalanine moiety is primarily responsible for high cytotoxicity.
  • The stereocenter in the dihydroisocoumarine structure has less impact on toxicity.
  • Differential cytotoxic and apoptotic effects were observed among the stereoisomers.

Conclusions:

  • Stereochemistry significantly influences ochratoxin A's cytotoxic and apoptotic potential.
  • The phenylalanine moiety's configuration is a key determinant of ochratoxin A's toxicity.
  • Further research can explore structure-activity relationships for targeted detoxification strategies.

More Related Videos

High Throughput, Real-time, Dual-readout Testing of Intracellular Antimicrobial Activity and Eukaryotic Cell Cytotoxicity09:09

High Throughput, Real-time, Dual-readout Testing of Intracellular Antimicrobial Activity and Eukaryotic Cell Cytotoxicity

Published on: November 16, 2016

Related Concept Videos

Oxidation of Alkenes: Syn Dihydroxylation with Osmium Tetraoxide02:44

Oxidation of Alkenes: Syn Dihydroxylation with Osmium Tetraoxide

Alkenes are converted to 1,2-diols or glycols through a process called dihydroxylation. It involves the addition of two hydroxyl groups across the double bond with two different stereochemical approaches, namely anti and syn. Dihydroxylation using osmium tetroxide progresses with syn stereochemistry.
Stereoisomerism of Cyclic Compounds02:33

Stereoisomerism of Cyclic Compounds

In this lesson, we delve into the role of ring conformation and its stability, which determines the spatial arrangement and, consequently, the molecular symmetry and stereoisomerism of cyclic compounds. 1,2-Dimethylcyclohexane is used as a case study to evaluate the possible number of stereoisomers. Here, given the multiple (n = 2) chiral centers, there are 2n = 4 possible configurations that lack a plane of symmetry, as the ring skeleton exists in a non-planar chair conformation. In addition,...
Bioactivation and Tissue Toxicity01:25

Bioactivation and Tissue Toxicity

Bioactivation is a metabolic process that transforms less reactive substances into highly reactive metabolites, initiating tissue toxicity. This transformation can lead to various toxic effects, including carcinogenesis and teratogenesis. Reactive metabolites are classified into two main types: electrophiles and free radicals.Electrophiles are electron-deficient species and are produced primarily by the enzyme cytochrome P-450 during the metabolism of compounds containing carbon, nitrogen, or...
Stereoisomers02:32

Stereoisomers

On the basis of mirror symmetry, stereoisomers of an organic molecule can be further classified into diastereomers and enantiomers. Diastereomers are stereoisomers that are not mirror images of each other. Substituted alkenes, such as the cis and trans isomers of 2-butene, are diastereomers, as these molecules exhibit different spatial orientations of their constituent atoms, are not mirror images of each other, and do not interconvert. Here, the interconversion is suppressed due to restricted...
Stereoisomerism02:52

Stereoisomerism

Isomerism in Complexes
Isomers are different chemical species that have the same chemical formula.
Transition metal complexes often exist as geometric isomers, in which the same atoms are connected through the same types of bonds but with differences in their orientation in space. Coordination complexes with two different ligands in the cis and trans positions from a ligand of interest form isomers. For example, the octahedral [Co(NH3)4Cl2]+ ion has two isomers (Figure 1) In the cis...