Some attempts to employ the singlet oxygen generated from molybdate-catalyzed decomposition of hydrogen peroxide are presented. Reduction of ascaridole with diimide is also described, along with the preliminary results of the cleavage study using Fe-cysteinate as a simple model for Fe-S type redox species. There were strong indica-tions that S-alkylation occurred as observed in similar cleavage of the potent antimalarial qinghaosu.
A [1,2]dioxolane-type peroxide was synthesized and tested for its cleavage behavior with Fe2+-cysteinate as a simple model of biological redox species. No S-alkylation product was observed.
Several simple analogues of peroxyplakoric acid were synthesized by using Kobayashi＇s method to construct the key 1,2-dioxane core and tested in vitro for antimalarial activity. The scope and limitation of the method was also briefly examined.
N-Acyl-β-hydroxy-4-phenyl-oxazolidinethiones could be rapidly converted into their ethyl thiol esters in high yields by treatment with EtSH at 0 ℃ in CH3CN or 9 ： 1 （V ： V） THF-H2O in the presence of a catalytic amount of K2CO3.
