Synthesis and Enantiomeric Separation of a Novel Spiroketal Derivative: A Potent Human Telomerase Inhibitor with High in Vitro Anticancer Activity

Numerous complex natural products containing spiroketals framework, with a wide range of important biological activities, have been isolated over the years from marine or terrestrial sources. Many groups investigated the possibility to reduce the complexity of spiroketal natural products while preserving their biological activity, showing that simple natural inspired spiroketals can be privileged scaffolds for new interesting lead compounds. We have synthesized a new structurally simplified spiroketal that has shown a potent antitumor activity against tumor cells of different nature and histotype. The simple spiroketalic structure of this compound has three stereocentres and its synthesis afforded a stereoisomeric mixture. We carried out the synthesis and the characterization of the stereoisomeric mixture, the stereoisomeric separation and the biological evaluation both of the stereoisomeric mixture and the enantiomerically pure spiroketals.