Alkaloids isolated from Tabernaemontana bufalina display xanthine oxidase inhibitory activity

Phytochemistry. 2019 Oct:166:112060. doi: 10.1016/j.phytochem.2019.112060. Epub 2019 Jul 11.

Abstract

Continued interest in bioactive alkaloids led to the isolation of four undescribed alkaloids along with 74 known ones from the aerial parts of Tabernaemontana bufalina Lour. The structures of the yet undescribed alkaloids were elucidated based on NMR, IR, UV, MS and CD spectroscopic data and X-ray crystal diffraction and, according to the plant source, named as taberhaines A-D (1-4). The known compounds comprised of 66 monoterpenoid indole, three carboline and five isoquinoline alkaloids. Among them, the known apparicine inhibited significantly the activity of xanthine oxidase, which plays an important role for gout, with an IC50 value of 0.65 μM, compared to the standard drug allopurinol (IC50 = 0.60 μM).

Keywords: Alkaloid; Apparicine; Taberhaines A–D; Tabernaemontana bufalina apocynaceae; Xanthine oxidase inhibitor.

MeSH terms

  • Alkaloids / chemistry*
  • Alkaloids / isolation & purification
  • Alkaloids / pharmacology*
  • Catalytic Domain
  • Enzyme Inhibitors / chemistry*
  • Enzyme Inhibitors / isolation & purification
  • Enzyme Inhibitors / pharmacology*
  • Inhibitory Concentration 50
  • Models, Molecular
  • Tabernaemontana / chemistry*
  • Xanthine Oxidase / antagonists & inhibitors*
  • Xanthine Oxidase / chemistry

Substances

  • Alkaloids
  • Enzyme Inhibitors
  • Xanthine Oxidase