New 6-arylvinyl-and 6-adamantylvinyl-substituted 1, 2, 4-trioxanes (13a-g and 14a, b) have been prepared and evaluated for antimalarial activity against multidrug resistant Plasmodium yoelii nigeriensis in mice by both oral and intramuscular routes. While all the 6-
![3-[1-(4-chlorophenyl)ethenyl]-1,2,5-trioxaspiro[5.5]undecan-9-one Structure](https://image.chemsrc.com/caspic/096/889099-43-8.png)
![3-(1-phenylethenyl)-1,2,5-trioxaspiro[5.5]undecan-9-one Structure](https://image.chemsrc.com/caspic/104/678967-25-4.png)
![3-[1-(4-phenylphenyl)ethenyl]-1,2,5-trioxaspiro[5.5]undecan-9-one Structure](https://image.chemsrc.com/caspic/359/678967-36-7.png)