Stictic acid derivatives from the lichen Usnea articulata and their antioxidant activities

J Nat Prod. 2007 Jul;70(7):1218-20. doi: 10.1021/np070145k. Epub 2007 Jul 13.

Abstract

Two new beta-orcinol depsidones, 1 and 2, together with 13 known compounds were isolated from the lichen Usnea articulata. The structures of 1 and 2 were elucidated by spectroscopic analyses and those of known compounds by comparison of their spectroscopic data with literature values or by direct comparison with authentic standards. Compounds 1, 2, and 5 exhibited moderate antiradical activity in the 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay. The depsidones 4 and 5 showed better superoxide anion scavenging activity (IC50 = 566 and 580 microM, respectively) than quercetin (IC50 = 754 microM).

MeSH terms

  • Antioxidants / chemistry
  • Antioxidants / isolation & purification*
  • Antioxidants / pharmacology*
  • Biphenyl Compounds
  • Depsides / chemistry
  • Depsides / isolation & purification*
  • Depsides / pharmacology*
  • Free Radical Scavengers / chemistry
  • Free Radical Scavengers / isolation & purification*
  • Free Radical Scavengers / pharmacology
  • Heterocyclic Compounds, 4 or More Rings / chemistry
  • Heterocyclic Compounds, 4 or More Rings / isolation & purification*
  • Heterocyclic Compounds, 4 or More Rings / pharmacology
  • Indonesia
  • Inhibitory Concentration 50
  • Lactones / chemistry
  • Lactones / isolation & purification*
  • Lactones / pharmacology*
  • Molecular Structure
  • Oxepins / chemistry
  • Oxepins / isolation & purification*
  • Oxepins / pharmacology
  • Picrates / pharmacology
  • Quercetin / pharmacology
  • Superoxides / pharmacology
  • Usnea / chemistry*

Substances

  • Antioxidants
  • Biphenyl Compounds
  • Depsides
  • Free Radical Scavengers
  • Heterocyclic Compounds, 4 or More Rings
  • Lactones
  • Oxepins
  • Picrates
  • stictic acid
  • Superoxides
  • depsidone
  • Quercetin
  • 1,1-diphenyl-2-picrylhydrazyl