Antimalarial, antimycobacterial and antiproliferative activity of phenyl substituted mixed tetraoxanes

Mixed tetraoxanes of the 4-phenyl-substituted cyclohexyl-spirotetraoxacyclohexyl-spirocholate series have been prepared and evaluated as possible antimalarials, anti-proliferatives and antimycobacterials. The activity of the (4R or S)-phenyl series against P falciarum D6 and W2 strains was found to be at the level of artemisinin. with two compounds. the acid 4 and the amide 6, exhibiting encouraging anti-TB activity as well. Very promising in vitro results of the said tetraoxanes were obtained against solid tumours and, in some instances. the activity against a selected number of cell lines was higher than that of the antitumor drug paclitaxel.