Related Experiment Video
Updated: Jul 13, 2026

Multimodal Nonlinear Hyperspectral Chemical Imaging Using Line-Scanning Vibrational Sum-Frequency Generation Microscopy
Published on: December 1, 2023
Using unsymmetrical indirect covariance processing to calculate GHSQC-COSY spectra
Gary E Martin1, Bruce D Hilton, Patrick A Irish
1Schering-Plough Research Institute, Summit, New Jersey 07901, USA. gary.martin@spcorp.com
Abstract:
GHSQC-TOCSY experiments allow sorting of proton-proton connectivity information as a function of (13)C chemical shift. GHSQC-TOCSY is a relatively insensitive 2D NMR experiment. Given two coherence transfer experiments, A --> B and A --> C, it is possible to indirectly determine B <--> C. Unsymmetrical indirect covariance processing of a (1)H- (13)C GHSQC and a GCOSY spectrum afforded a GHSQC-COSY spectrum, with an information content analogous to a GHSQC-TOCSY experiment. However, GHSQC-TOCSY is of significantly lower sensitivity and the data require considerably more time to acquire than either of the component experiments. Investigators needing access to GHSQC-TOCSY type data can, in principle, access it from more readily acquired 2D NMR data. Strychnine ( 1) was used as a model compound to illustrate this capability.
Related Concept Videos
2D NMR: Heteronuclear Single-Quantum Correlation Spectroscopy (HSQC)
2D NMR: Overview of Heteronuclear Correlation Techniques
2D NMR: Homonuclear Correlation Spectroscopy (COSY)
2D NMR: Overview of Homonuclear Correlation Techniques
COSY90 is the standard two-dimensional (2D) COSY experiment that...
IR Spectroscopy: Hooke's Law Approximation of Molecular Vibration
According to Hooke's law, the vibrational frequency is directly proportional to the...
¹H NMR: Interpreting Distorted and Overlapping Signals
As Δν decreases and the signals move closer, the doublets appear increasingly distorted. The intensities of the inner lines increase at the cost of those of the outer lines as the signals are slanted or...