Synthetic transformations of sesquiterpene lactones. IV.* Synthesis and transformations of gem-dichlorocyclopropyl-substituted isoalantolactone derivatives

Chloro-containing compounds, the ratio of which depended on the reaction time, were formed via reaction of isoalantolactone and CHCl3 through the action of a phase-transfer catalyst. 4,15-(2,2-Dichlorocycloprop1-yl)isoalantolactone exhibited high activity and selectivity in the Heck reaction with arylhalides. Data for the cytotoxicity of the synthesized chloro-derivatives of isoalantolactone in CEM-13, MT-4, and U-937 cell tumor models were obtained. The doses of the most active compounds inhibiting the viability of tumor cells by 50 % (CCID50) were 3.2–11.1 1 M.