Patents
The invention provides an improved method for the preparation of artemether from artemisinin in one pot in just about 4 hours. It comprises: Reduction of artemisinin with less quantity of sodium borohydride in methanol at 0 to -5 degree C. into dihydroartemisinin which occurs without isolation of the methylated (metherified) product in the presence of solid/liquid acid catalyst in the same pot at room temperature. After usual workup, the impure artemether purified by silica gel column chromatography in 1:5 ratio, yielded 80-82% (w/w) pure alpha, beta artemether. Artemether prepared from the process is useful for the treatment of uncomplicated, severe complicated and multi drug resistant malaria.