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Updated: May 18, 2026

Synthesis and Structure Determination of µ-Conotoxin PIIIA Isomers with Different Disulfide Connectivities
Published on: October 2, 2018
Experimental and theoretical investigation of 1J(CC) and (n)J(CC) coupling constants in strychnine
R Thomas Williamson1, Alexei V Buevich, Gary E Martin
1Merck Research Laboratories Discovery and Preclinical Sciences, Process and Analytical Chemistry-Structure Elucidation Group, Rahway, New Jersey 07065, USA.
Abstract:
A relatively unexplored and unexploited means of establishing molecular structure, stereochemistry, and probing vicinal bond angles is through the use of long-range (13)C-(13)C coupling constants. The measurement of these multifunctional, diagnostic (3)J(CC) couplings has not been reported on sample amounts viable for the practicing organic chemist. A generalized protocol for the measurement of (1)J(CC) and (3)J(CC) couplings using a 4.6 mg sample of strychnine as a model compound is described, and the utility of DFT calculations for the prediction of these useful molecular descriptors and the congruence of the calculated and experimental data is demonstrated.
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