Artemisinin and its derivatives, such as artemether, are highly sensitive compounds, which require careful optimized production processes for their manufacture. Due to robustness issues, the manufacturing procedure of the reduction of artemisinin with potassium borohydride to dihydroartemisinin was reinvestigated. The most important factor for obtaining optimal yields is to ensure low levels of contamination of potassium hydroxide in potassium borohydride. Application of a lower reaction temperature, fast addition rate of potassium borohydride, and careful control of the pH during the quench with acid are further important parameters in guaranteeing a robust process. In the redesign of the conversion of dihydroartemisinin to artemether, the yield was increased, and dichloromethane was replaced by the ecologically friendlier methyl acetate. A robust manufacturing process for artemether is now at hand, allowing the production of this important medicine reliably and in good quality and yield.

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Starting from polystyrene, a simple four-step synthesis of polymer-supported alkyltriazenes (alkyl=Me, Et, benzyl) is described. With this synthesis, a loading capacity of 2.2 mmol g(-1) can be reached. The most prominent application of these polymer-supported reagents is the rapid, highly selective and high-yielding esterification of carboxylic acids, which involves a simple "mix and filter off" procedure at room temperature. If stored in a refrigerator, these reagents are stable for many months and they can be recycled several times.

The naturally‐occurring ionophore X206, originally isolated for its antibacterial activity, also exhibits broad insecticidal and acaricidal activity. This summary reports structure/activity studies with X206 and 34 derivatives as well as mode of action studies. Although many compounds showed promising insecticidal activity, it was only of a contact activity nature; furthermore, the acute LD50 of the compounds in rats precluded further development of these compounds. © 1999 Society of Chemical Industry