A-ring and E-ring modifications of the cytotoxic alkaloid Luotonin A: Synthesis, computational and biological studies
- Bioorg Med Chem. 2020 May 1;28(9):115443. doi: 10.1016/j.bmc.2020.115443.
- 1. Department of Pharmaceutical Chemistry, University of Vienna, Althanstraße 14, A-1090 Vienna, Austria.
- 2. Institute of Cancer Research and Comprehensive Cancer Center, Medical University of Vienna, Borschkegasse 8a, A-1090 Vienna, Austria.
- 3. Department of Pharmaceutical Chemistry, University of Vienna, Althanstraße 14, A-1090 Vienna, Austria. Electronic address: [email protected].
A series of new Luotonin A derivatives with substituents at rings A and E was synthesized, together with some E-ring-unsubstituted derivatives. Subsequently, the compound library was examined in silico for their binding into a previously proposed site in the DNA/Topoisomerase I binary complex. Whereas no convincing correlation between docking scores and biological data from in vitro assays could be found, one novel 4,9-diamino Luotonin A derivative had strong antiproliferative activity based on massive G2/M phase arrest. As this biological activity clearly differs from the reference compound Camptothecin, this strongly indicates that at least some Luotonin A derivatives may be potent antiproliferative agents, however with a different mode of action.