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

¹H NMR of Conformationally Flexible Molecules: Temporal Resolution00:52

¹H NMR of Conformationally Flexible Molecules: Temporal Resolution

795
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...
795
¹³C NMR: Distortionless Enhancement by Polarization Transfer (DEPT)01:20

¹³C NMR: Distortionless Enhancement by Polarization Transfer (DEPT)

993
When proton-coupled carbon-13 spectra are simplified by a broadband proton decoupling technique, structural information about the coupled protons is lost. Distortionless enhancement by polarization transfer (DEPT) is a technique that provides information on the number of hydrogens attached to each carbon in a molecule. While the DEPT experiment utilizes complex pulse sequences, the pulse delay and flip angle are specifically manipulated. The resulting signals have different phases depending on...
993
Properties of Enantiomers and Optical Activity02:24

Properties of Enantiomers and Optical Activity

16.6K
It is essential to understand the difference between chiral and achiral interactions and the implications thereof in optical activity and their applications. Just as our feet, which are chiral, interact uniquely with chiral objects, such as a pair of shoes, but identically with achiral socks, enantiomers of a molecule exhibit different properties only when they interact with other chiral media. An example of a significant implication from this facet is the phenomenon known as optical activity,...
16.6K
NMR Spectroscopy of Aromatic Compounds01:14

NMR Spectroscopy of Aromatic Compounds

4.4K
Aromatic compounds can be identified or analyzed using proton NMR and carbon‐13 NMR. Typically, aromatic hydrogens or hydrogens directly bonded to the aromatic rings are strongly deshielded by the aromatic ring current. Therefore, they absorb in the range of 6.5–8.0 ppm in proton NMR spectra. For instance, aromatic hydrogens directly bonded to the benzene ring absorb at 7.3 ppm. However, aromatic hydrogens of larger rings absorb farther upfield or downfield than the ideal range.
4.4K
¹H NMR of Conformationally Flexible Molecules: Variable-Temperature NMR01:15

¹H NMR of Conformationally Flexible Molecules: Variable-Temperature NMR

1.0K
The axial and equatorial protons in cyclohexane can be distinguished by performing a variable-temperature NMR experiment. In this process, except for one proton, the remaining eleven protons are replaced by deuterium. The deuterium substitution avoids the possible peak splitting caused by the spin-spin coupling between the adjacent protons. The remaining proton flips between the axial and equatorial positions.
1.0K
Chirality at Nitrogen, Phosphorus, and Sulfur02:30

Chirality at Nitrogen, Phosphorus, and Sulfur

5.7K
Chirality is most prevalent in carbon-based tetrahedral compounds, but this important facet of molecular symmetry extends to sp3-hybridized nitrogen, phosphorus and sulfur centers, including trivalent molecules with lone pairs. Here, the lone pair behaves as a functional group in addition to the other three substituents to form an analogous tetrahedral center that can be chiral.
A consequence of chirality is the need for enantiomeric resolution. While this is theoretically possible for all...
5.7K

You might also read

Related Articles

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

Sort by
Same author

Rotational spectrum of laser-ablated mannitol: a conformational and photofragmentation study.

Physical chemistry chemical physics : PCCP·2026
Same author

Stepwise Hydration Reveals Conformational Switching in Chiral Prolinol.

Journal of the American Chemical Society·2025
Same author

Conformational Analysis of 3-Indoleacetamide: Unveiling Structural Rigidity in the Tryptophan-Derived Bioactive Molecule Family.

Molecules (Basel, Switzerland)·2025
Same author

Fragmentation Dynamics of Benzoyl Peroxide: Insights from Rotational Spectroscopy.

The journal of physical chemistry letters·2025
Same author

Five structures of the Pro-Gly dipeptide unveiled by laser ablation rotational spectroscopy.

Physical chemistry chemical physics : PCCP·2025
Same author

Stabilization of Zwitterionic Versus Canonical Glycine by DMSO Molecules.

Pharmaceuticals (Basel, Switzerland)·2025

Related Experiment Video

Updated: May 22, 2025

Atomic Scale Structural Studies of Macromolecular Assemblies by Solid-state Nuclear Magnetic Resonance Spectroscopy
14:55

Atomic Scale Structural Studies of Macromolecular Assemblies by Solid-state Nuclear Magnetic Resonance Spectroscopy

Published on: September 17, 2017

15.3K

Elucidating the Three-Dimensional Structure of Piracetam through Rotational Spectroscopy.

S Mato1, S Municio1, J L Alonso1

  • 1Química Física-Química Inorgánica Department, Universidad de Valladolid, Grupo de Espectroscopia Molecular (GEM), Edificio Quifima Laboratorios de Espectroscopia y Bioespectroscopia, Parque Científico, Universidad de Valladolid, 47011, Valladolid, Spain.

Chemistryopen
|March 15, 2025
PubMed
Summary
This summary is machine-generated.

Researchers identified the most stable structures of piracetam, a nootropic drug, using microwave spectroscopy. The primary form features an exo ring configuration stabilized by a hydrogen bond, with a low energy barrier to interconversion with an endo form.

Keywords:
FTMW spectroscopyconformersdrugsnon-covalent interactionspiracetam

More Related Videos

Line Shape Analysis of Dynamic NMR Spectra for Characterizing Coordination Sphere Rearrangements at a Chiral Rhenium Polyhydride Complex
10:52

Line Shape Analysis of Dynamic NMR Spectra for Characterizing Coordination Sphere Rearrangements at a Chiral Rhenium Polyhydride Complex

Published on: July 27, 2022

2.6K
One-pot Microwave-assisted Conversion of Anomeric Nitrate-esters to Trichloroacetimidates
06:00

One-pot Microwave-assisted Conversion of Anomeric Nitrate-esters to Trichloroacetimidates

Published on: January 15, 2018

7.4K

Related Experiment Videos

Last Updated: May 22, 2025

Atomic Scale Structural Studies of Macromolecular Assemblies by Solid-state Nuclear Magnetic Resonance Spectroscopy
14:55

Atomic Scale Structural Studies of Macromolecular Assemblies by Solid-state Nuclear Magnetic Resonance Spectroscopy

Published on: September 17, 2017

15.3K
Line Shape Analysis of Dynamic NMR Spectra for Characterizing Coordination Sphere Rearrangements at a Chiral Rhenium Polyhydride Complex
10:52

Line Shape Analysis of Dynamic NMR Spectra for Characterizing Coordination Sphere Rearrangements at a Chiral Rhenium Polyhydride Complex

Published on: July 27, 2022

2.6K
One-pot Microwave-assisted Conversion of Anomeric Nitrate-esters to Trichloroacetimidates
06:00

One-pot Microwave-assisted Conversion of Anomeric Nitrate-esters to Trichloroacetimidates

Published on: January 15, 2018

7.4K

Area of Science:

  • Physical Chemistry
  • Molecular Spectroscopy
  • Medicinal Chemistry

Background:

  • Piracetam is a widely studied nootropic drug.
  • Understanding the conformational preferences of piracetam is crucial for its pharmacological activity.
  • Previous studies have not fully elucidated the most stable structures in isolation.

Purpose of the Study:

  • To determine the most stable molecular structures of piracetam in isolated conditions.
  • To investigate the conformational landscape of piracetam using high-resolution spectroscopy.
  • To characterize the stabilizing interactions within piracetam conformers.

Main Methods:

  • Chirped pulse Fourier transform microwave (CP-FTMW) spectroscopy.
  • Laser ablation source for generating gaseous piracetam.
  • Broadband rotational spectrum analysis in the 6.0–14.0 GHz range.

Main Results:

  • Two distinct conformers of piracetam were experimentally observed.
  • The most stable conformer exhibits an exo ring configuration.
  • This stable conformer is primarily stabilized by an intramolecular N-H···O=C hydrogen bond.
  • A second, nearly equally stable, endo conformer was also identified.
  • A low interconversion barrier between the exo and endo conformers was determined.

Conclusions:

  • The study provides definitive structural information on piracetam conformers in the gas phase.
  • The identified N-H···O=C hydrogen bond is key to the stability of the major piracetam conformer.
  • The low interconversion barrier suggests conformational flexibility relevant to its biological function.