Sesquiterpene Metylenelactones in a Palladium-Catalyzed Cross-Coupling Reactio

摘要

Compounds containing an α-methylene-γ-lactone fragment, in particular sesquiterpene lactones, have attracted attention for the past 50 years owing to their diverse physiological activity, including antitumor properties [1]. The biological activity of sesquiterpene lactones are known to result from their behavior as alkylating agents. These compounds can form in vivo adducts with nucleophilic regions of biomole-cules (like products of the Michael reaction with free sulfhydryl or amino groups) [2]. Eudesmane-type sesquiterpene lactones show antiproliferative activity in vitro in tumor cells MK-1, HeLa, and B16F10 [3]. The capability to inhibit the growth of human tumor cells (COLO-205, HT-29, HL-60, AGS) is explained by the initiation of apoptosis, which is considered to be associated with activation of a caspase cascade in these cells [4-6].