Collect. Czech. Chem. Commun. 2006, 71, 1229-1238

Dimeric Ecdysteroid Analogues and Their Interaction with the Drosophila Ecdysteroid Receptor

Juraj Harmathaa,*, Miloš Buděšínskýa, Karel Vokáča, Laurence Dinanb and René Lafontc

a Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, Flemingovo nám. 2, 166 10 Prague 6, Czech Republic
b Department of Biological Sciences, University of Exeter, Prince of Wales Road, Exeter, EX4 4PS, U.K
c Laboratoire Protéines - Biochimie structurale et fonctionnelle, Université P. et M. Curie, 7 Quai Saint-Bernard, 75252 Paris 05, France


Three structurally related specific ecdysteroid derivatives, 7,7'-dimers of 14-deoxy-8(14)-ene transformed 20-hydroxyecdysone, ponasterone A and ajugasterone C, were obtained by photochemical transformation. The structures of the dimeric ecdysteroids were identified mainly by NMR spectroscopy supported by MS and IR spectroscopy. Yields of the dimerisation products were dependent on the reactant concentrations and photoreaction conditions. Inert gas atmosphere supported high yields, whereas oxygen atmosphere fully prevented the dimer formation. All the three dimers retained a rather high agonistic activity at the ecdysteroid receptor in the Drosophila BII bioassay when compared with the relevant original ecdysteroids.

Keywords: Steroids; Ecdysteroids; 20-Hydroxyecdysone; Ponasterone A; Ajugasterone C; Photochemical transformations; Drosophila melanogaster BII bioassay; Ecdysteroid receptor agonists; NMR spectroscopy.

References: 22 live references.