The first enantioselective total synthesis of tonantzitlolone, a novel 15-membered macrocyclic diterpene, utilized a Julia olefination, a highly selective, potassium enolate-based anti-Felkin aldol reaction, and an E-selective ring-closing metathesis as key C-C bond-forming steps. The absoluteconfiguration of tonantzitlolone is established.
The natural diterpene tonantzitlolone A and its synthetic enantiomer inhibit cell proliferation and kinesin-5 function
作者:Tobias J. Pfeffer、Florenz Sasse、Christoph F. Schmidt、Stefan Lakämper、Andreas Kirschning、Tim Scholz
DOI:10.1016/j.ejmech.2016.02.022
日期:2016.4
Tonantzitlolone A, a diterpene isolated from the Mexican plant Stillingia sanguinolenta, shows cytostatic activity. Both the natural product tonantzitlolone A and its synthetic enantiomer induce monoastral spindle formation in cell experiments which indicates inhibitory activity on kinesin-5 mitotic motor molecules. These inhibitory effects on kinesin-5 could be verified in in vitro single-molecule motility assays, where both tonantzitlolones interfered with kinesin-5 binding to its cellular interaction partner microtubules in a concentration-dependent manner, yet with a larger effect of the synthetic enantiomer. In contrast to kinesin-5 inhibition, both tonantzitlolone A enantiomers did not affect conventional kinesin-1 function; hence tonantzitlolones are not unspecific kinesin inhibitors. The observed stronger inhibitory effect of the synthetic enantiomer demonstrates the possibility to enhance the overall moderate anti-proliferative effect of the lead compound tonantzitlolon A by chemical modification. (C) 2016 Elsevier Masson SAS. All rights reserved.