Electrochemical synthesis of euglobal-G1, -G2, -G3, -G4, -T1 and -IIc

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Kazuhiro Chiba, Takaaki Arakawa and Masahiro Tada


Abstract

Six natural euglobals were synthesized by electrochemical methods. In a key step, cycloaddition between in situ generated quinomethanes and terpenes was performed on the surface of PTFE-fibre coated electrode to give natural products using 2,3-dichloro-5,6-dicyano-p-hydroquinone (DDQH2) as a redox mediator. In this reaction system, biomimetic generation and cycloaddition of the unstable quinomethanes were efficiently completed by the selective oxidation of cresol derivatives.


References

  1. M. Takahashi, T. Konoshima, K. Fujita, S. Yoshida, H. Nishimura, H. Hokuda, H. Nishino, A. Iwashima and M. Kozuka, Chem. Pharm. Bull., 1990, 38, 2737.
  2. M. Kozuka, T. Sawada, F. Kasahara, E. Mizuta, T. Amano, T. Komiya and M. Goto, Chem. Pharm. Bull., 1982, 30, 1952 CAS.
  3. E. L. Ghisalberti, Phytochemistry, 1995, 41, 7 CrossRef CAS.
  4. (a) K. Chiba, J. Sonoyama and M. Tada, J. Chem. Soc., Chem. Commun., 1995, 1381 RSC; (b) K. Chiba, T. Arakawa and M. Tada, Chem. Commun., 1996, 1763 RSC.
  5. (a) V. D. Parker, Electrochim. Acta, 1973, 18, 519 CrossRef CAS; (b) O. Hammerich and V. D. Parker, Acta Chem. Scand. Ser. B, 1982, 36, 63 Search PubMed; (c) J. Q. Chambers, in Chem. Quinoid Compd., Vol. 2, ed. S. Patai and Z. Rappoport, Wiley, Chichester, UK, 1988, p. 719 Search PubMed.
  6. (a) U. H. Brinker, M. Tyner III and W. M. Jones, Synthesis, 1975, 671 CrossRef CAS; (b) J. H. P. Utley and G. G. Rosenberg, in Novel Trends in Electroorganic Synthesis, ed. S. Torii, Springer-Verlag, Tokyo, 1998, p. 45 Search PubMed.
  7. T. Meikle and R. J. Stevens, J. Chem. Soc., Perkin Trans. 1, 1978, 1303 RSC.
  8. R. H. Mitchell and Y. H. Lai, Tetrahedron Lett., 1980, 21, 2637 CrossRef CAS.
  9. T. Sala and M. V. Sargent, J. Chem. Soc., Perkin Trans. 1, 1979, 2593 RSC.
  10. (a) M. Takasaki, T. Konoshima, M. Kozuka, M. Haruna, K. Ito and T. Shingu, Chem. Pharm. Bull., 1994, 42, 2591 CAS; (b) M. Kokumai, T. Konoshima and M. Kozuka, J. Nat. Prod., 1991, 54, 1082 CrossRef CAS.
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