Journal of Wood Science

, Volume 52, Issue 1, pp 90–92 | Cite as

Facile synthesis of rubiadin by microwave heating

  • Toshiyuki Takano
  • Tomomi Kondo
  • Fumiaki Nakatsubo


Rubiadin (4) (1,3-dihydroxy-2-methylanthraquinone), which is one of the natural dyes from the roots of Rubiaceae, was synthesized from phthalic anhydride (1) and 2,6-dihydroxytoluene (3) by two reaction steps, that is, a Friedel-Crafts reaction with AlCl3 and a cyclization with H2SO4/HBO2. Microwave heating resulted in remarkable acceleration of the reaction rate in the first reaction, and had an effect in reducing the reaction time and increasing the yield of rubiadin (4) in the second reaction.

Key words

Synthesis Rubiadin Hydroxyanthraquinone Microwave Friedel-Crafts acylation 


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.


  1. 1.
    Lee HH (1969) Coloring matters from Prismatomeris malayana. Phytochemistry 8:501–503CrossRefGoogle Scholar
  2. 2.
    Jasril, Lajis NH, Abdullah MA, Ismail NH, Ali AM, Marziah M, Ariff AB, Kitajima M, Takayama H, Alimi N (2000) Anthraquinones from cell suspension culture of Morinda elliptica. Nat Prod Sci 6:40–43Google Scholar
  3. 3.
    Ali AM, Ismail NH, Mackeen MM, Yazan LS, Mohamed SM, Ho ASH, Lajis NH (2000) Antiviral cyototoxic and antimicrobial activities of anthraquinones isolated from the root of Morinda elliptica. Pharm, Biol 38:298–301CrossRefGoogle Scholar
  4. 4.
    Hirose Y (1960) Syntheses of damnacanthal, damnacanthol, norjuzunal and norjuzunol, the coloring matters of Damnacanthus spp. Chem Pharm Bull 8:417–426Google Scholar
  5. 5.
    Chari VM, Neelakantan S, Seshadri TR (1966) A convenient synthesis of rubiadin. Indian J Chem 4:330–331Google Scholar
  6. 6.
    Courchesne M, Brassard P (1993) Identification and characterization of naturally occurring rubiadins. J Nat Prod 56:722–730CrossRefGoogle Scholar
  7. 7.
    Boisvert L, Brassard P (1989) Naturally occurring rubiadins. Chem Lett 1055-1058Google Scholar
  8. 8.
    Zhao H, Biehl E (1995) Preparation of naturally occurring anthraquinones using the aryne reaction. J Nat Prod 58:1970–1974CrossRefGoogle Scholar
  9. 9.
    Lidstrom P, Tierney J, Wathey B, Westman J (2001) Microwave assisted organic synthesis — a review. Tetrahedron 57:9225–9283CrossRefGoogle Scholar
  10. 10.
    Nakahara H (1976) Boric acid (in Japanese). In: The Chemical Society of Japan (ed) Shi-Jikkenkagaku Koza 8-I. Maruzen, Tokyo, p 364Google Scholar

Copyright information

© The Japan Wood Research Society 2006

Authors and Affiliations

  • Toshiyuki Takano
    • 1
  • Tomomi Kondo
    • 1
  • Fumiaki Nakatsubo
    • 1
  1. 1.Division of Forest and Biomaterials Science, Graduate School of AgricultureKyoto UniversitySakyo-ku, KyotoJapan

Personalised recommendations