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

Stability of Substituted Cyclohexanes02:30

Stability of Substituted Cyclohexanes

12.5K
This lesson discusses the stability of substituted cyclohexanes with a focus on energies of various conformers and the effect of 1,3-diaxial interactions.
The two chair conformations of cyclohexanes undergo rapid interconversion at room temperature. Both forms have identical energies and stabilities, each comprising equal amounts of the equilibrium mixture. Replacing a hydrogen atom with a functional group makes the two conformations energetically non-equivalent.
For example, in...
12.5K
Chair Conformation of Cyclohexane02:02

Chair Conformation of Cyclohexane

14.4K
The chair conformation is the most stable form of cyclohexane due to the absence of angle and torsional strain. The absence of angle strain is a result of cyclohexane’s bond angle being very close to the ideal tetrahedral bond angle of 109.5° in its chair conformer. Similarly, the torsional strain is also absent owing to the perfectly staggered arrangement of bonds.
The hydrogen atoms linked to carbons are arranged in two different axial and equatorial orientations to achieve this...
14.4K
Stability of Conjugated Dienes01:28

Stability of Conjugated Dienes

3.3K
Introduction
A comparison of the enthalpies of hydrogenation of dienes reveals that conjugated dienes release less heat on hydrogenation, rendering them more stable than their nonconjugated analogs.
3.3K
¹H NMR of Conformationally Flexible Molecules: Temporal Resolution00:52

¹H NMR of Conformationally Flexible Molecules: Temporal Resolution

820
At room temperature, the chair conformer of cyclohexane undergoes rapid ring flipping between two equivalent chair conformers at a rate of approximately 105 times per second. These two chair conformers are in equilibrium. The rapid ring flipping results in the interconversion of the axial proton to an equatorial proton and an equatorial to the axial proton. Such interconversions are too rapid and cannot be detected on the NMR timescale. Hence, the NMR spectrometer cannot distinguish between the...
820
Radical Reactivity: Steric Effects01:10

Radical Reactivity: Steric Effects

1.9K
The presence of electron-donating, electron-withdrawing, or conjugating groups adjacent to a radical center, imparts electronic stabilization to the radicals. Examples of such electronically-stabilized radicals are triphenylmethyl, tetramethylpiperidine‐N‐oxide, and 2,2‐diphenyl‐1‐picrylhydrazyl. These radicals are remarkably stable and are known as persistent radicals. Some of the persistent radicals can even be isolated and purified.
Along with electronic...
1.9K
Woodward–Hoffmann Selection Rules and Microscopic Reversibility01:34

Woodward–Hoffmann Selection Rules and Microscopic Reversibility

3.0K
Electrocyclic reactions, cycloadditions, and sigmatropic rearrangements are concerted pericyclic reactions that proceed via a cyclic transition state. These reactions are stereospecific and regioselective. The stereochemistry of the products depends on the symmetry characteristics of the interacting orbitals and the reaction conditions. Accordingly, pericyclic reactions are classified as either symmetry-allowed or symmetry-forbidden. Woodward and Hoffmann presented the selection criteria for...
3.0K

You might also read

Related Articles

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

Sort by
Same author

Structural Response of Pohlianin C to Heterocyclic Graft Incorporation.

The Journal of organic chemistry·2026
Same author

Frame-Shifted Synthesis of Oligoheterocycles as a Platform for Molecular Design.

Angewandte Chemie (International ed. in English)·2025
Same author

A Three-Component Path to Amino Thiadiazoles and Amino Oxadiazoles via a Nitrilium Ylide.

The Journal of organic chemistry·2025
Same author

A borindolizine platform for the design of fluorophores with tunable emissions.

Chemical science·2025
Same author

Pseudo-Ring Methodology to Control the Conformations of Macrocyclic Peptides.

Chemistry (Weinheim an der Bergstrasse, Germany)·2025
Same author

Terpenoid Cyclophanes with Planar Chirality.

Journal of the American Chemical Society·2024
Same journal

Gas-Responsive Metal-Organic Frameworks for Adaptive Thermal Energy Storage with Tunable Charge-Discharge Temperatures.

Journal of the American Chemical Society·2026
Same journal

Engineering a Thiamine-Dependent Benzoylformate Decarboxylase for Stereodivergent Radical C(sp<sup>3</sup>)-C(sp<sup>3</sup>) Bond Formation.

Journal of the American Chemical Society·2026
Same journal

Accelerated Directional Proton-Coupled Electron Transfer Enabled by Intrinsic Dipole Field in Biomimetic α-Helical Structure.

Journal of the American Chemical Society·2026
Same journal

Alternating Current-Driven Hydrogen Isotope Labeling of Aliphatic Amines Using 1,3-Propanedithiol as an Efficient Hydrogen Atom Transfer Reagent.

Journal of the American Chemical Society·2026
Same journal

Two-Dimensional van der Waals Polar Metal MoOBr<sub>2</sub>.

Journal of the American Chemical Society·2026
Same journal

Negatively Curved Chiral Bilayer Nanographene.

Journal of the American Chemical Society·2026
See all related articles

Related Experiment Video

Updated: Jun 16, 2025

Self-assembling Morphologies Obtained from Helical Polycarbodiimide Copolymers and Their Triazole Derivatives
09:22

Self-assembling Morphologies Obtained from Helical Polycarbodiimide Copolymers and Their Triazole Derivatives

Published on: February 7, 2017

7.8K

Stabilization of 310-Helices in Macrocycles Using Dominant Rotor Methodology.

Martynas J Širvinskas1, George J Saunders1, Monica Mitrache1

  • 1Davenport Research Laboratories, University of Toronto, 80 St. George St., Toronto, Ontario M5S 3H6, Canada.

Journal of the American Chemical Society
|August 19, 2024
PubMed
Summary
This summary is machine-generated.

Atropisomeric rotors stabilize rare 310-helices in macrocycles, a normally metastable state. These helical structures remain stable even after prolonged heating and can be selectively enriched.

More Related Videos

Structure of HIV-1 Capsid Assemblies by Cryo-electron Microscopy and Iterative Helical Real-space Reconstruction
12:38

Structure of HIV-1 Capsid Assemblies by Cryo-electron Microscopy and Iterative Helical Real-space Reconstruction

Published on: August 9, 2011

17.4K
Controlling the Size, Shape and Stability of Supramolecular Polymers in Water
16:24

Controlling the Size, Shape and Stability of Supramolecular Polymers in Water

Published on: August 2, 2012

18.6K

Related Experiment Videos

Last Updated: Jun 16, 2025

Self-assembling Morphologies Obtained from Helical Polycarbodiimide Copolymers and Their Triazole Derivatives
09:22

Self-assembling Morphologies Obtained from Helical Polycarbodiimide Copolymers and Their Triazole Derivatives

Published on: February 7, 2017

7.8K
Structure of HIV-1 Capsid Assemblies by Cryo-electron Microscopy and Iterative Helical Real-space Reconstruction
12:38

Structure of HIV-1 Capsid Assemblies by Cryo-electron Microscopy and Iterative Helical Real-space Reconstruction

Published on: August 9, 2011

17.4K
Controlling the Size, Shape and Stability of Supramolecular Polymers in Water
16:24

Controlling the Size, Shape and Stability of Supramolecular Polymers in Water

Published on: August 2, 2012

18.6K

Area of Science:

  • Chemical synthesis and structural biology
  • Supramolecular chemistry and peptide science

Background:

  • Stabilizing biologically relevant structural motifs is a significant challenge in chemistry.
  • Rare 310-helices are typically metastable and difficult to maintain in macrocyclic structures.

Purpose of the Study:

  • To investigate the stabilization of 310-helices in macrocycles using atropisomeric dominant rotors.
  • To explore the potential of these stabilized helices for applications requiring robust structural motifs.

Main Methods:

  • Solid-phase peptide synthesis for macrocycle preparation.
  • Extensive structural analysis and molecular dynamics (MD) simulations for solution structure determination.
  • Thermal stability assays to assess helicity retention.

Main Results:

  • Atropisomeric dominant rotors successfully stabilized 310-helices in macrocycles.
  • MD simulations provided evidence for stable 310-helix formation, overcoming the usual metastability.
  • The 310-helices demonstrated remarkable thermal stability, retaining helicity after heating to 100 °C for 72 hours.
  • Thermal enrichment of crude atropisomeric mixtures yielded 310-helical macrocycles with high selectivity (>20:1).

Conclusions:

  • Atropisomeric rotors are effective tools for stabilizing otherwise metastable 310-helical structures in macrocycles.
  • The demonstrated thermal stability and selective enrichment offer promising avenues for designing robust macrocyclic compounds.