Molecules (Jan 2020)

Crystallographic and NMR Investigation of Ergometrine and Methylergometrine, Two Alkaloids from <i>Claviceps Purpurea</i>

  • Fiorella Meneghetti,
  • Patrizia Ferraboschi,
  • Paride Grisenti,
  • Shahrzad Reza Elahi,
  • Matteo Mori,
  • Samuele Ciceri

DOI
https://doi.org/10.3390/molecules25020331
Journal volume & issue
Vol. 25, no. 2
p. 331

Abstract

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Ergometrine and methylergometrine are two alkaloids that are used as maleate salts for the prevention and control of postpartum hemorrhage. Although the two molecules have been known for a long time, few and discordant crystallographic and NMR spectroscopic data are available in the literature. With the aim of providing more conclusive data, we performed a careful NMR study for the complete assignment of the 1H, 13C, and 15N NMR signals of ergometrine, methylergometrine, and their maleate salts. This information allowed for a better definition of their conformational equilibria. In addition, the stereochemistry and the intermolecular interactions in the solid state of the two maleate salts were deeply investigated by means of single-crystal X-ray diffraction, showing the capability of these derivatives to act as both hydrogen-bond donors and acceptors, and evidencing a correlation between the number of intermolecular interactions and their different solubility.

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