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Total synthesis of qinghaosu G . Schmidt, W. Hofheinz, J. Am. Chem. Soc., 105, 624 (1983). Zhenjun Guan 2013.2.26. Introduction.
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Total synthesis of qinghaosuG. Schmidt, W. Hofheinz, J. Am. Chem. Soc., 105, 624 (1983) Zhenjun Guan 2013.2.26
Introduction • Since ancient time Artemisia annua also called qinghao has been used to treat fever in china. The effective constituent was lsolate by chinese scientist in 1972 named qinghaosu also known as Artemisinin. • It can be used to treat drug-resistant malaria which causes millions death every year in developing countries of Asia Africa and America.
This is the structure of qinhaosu. It is a sesquiterpene lactone containing a peroxide bridge. Which is found to be functional in treating malaria. As mentioned above, qinghaosu was first isolate from the plant in 1972. There is no precedent in the field of synthetic route toward this natural product until 1983. G.Schmid and W. hofheinz, two chemists of Hoffmann-La Roche first accomplished the total synthesis of the molecule.
Retrosynthesis (-)-Isopulegol
Forward synthesisPart1 1 1 2 3 5 4
Part 2 6 5 8 7
stereoselectivity 7b 7a
8 9 10 11
Stereospecificity 10a 10b
11 12 13
Summary • This is the paper showing the complete synthesis of qinghaosu • 12 step Total synthesis of the qinghaosu with a yield of 2.955% • Some steps remain to be improved.