Sentence Examples

  • The trioxyanthraquinones - purpurin, anthrapurpurin, anthragallol and flavopurpurin - are also very valuable dyestuffs.
  • Anthragallol is synthetically prepared by the condensation of benAoic and gallic acids with sulphuric acid OH i [[Cooh + I 10h - 2h20+ Hooc /Oh]] or from pyrogallol and phthalic anhydride in the presence of sulphuric acid or zinc chloride.