Deoxy artemisinin

As mentioned, qinghaosu chemically belongs to the cadinane sesquiterpene therefore, the other sesquiterpene components in A. annua have been given preferential attention. From indigenous A. annua L., continuous phytochemical studies by Chinese researches in the early 1980s led to the excavation of another ten sesquiterpenes including deoxy-artemisinin (14), artemisinin D (15), artemisinin... 

C/j-fused trioxanes, exemplified by (30), are readily deoxygenated by zinc and acetic acid (Equation (10)) <89H(28)673>. The c/j-l,2-diol (90) is formed. Formally, zinc is converted into zinc oxide and subsequently zinc acetate by solution in the acid. Artemisinin (9) and ) -artemether (23) are similarly deoxygenated to deoxyartemisinin (19) and deoxy-)S-artemether (91) by dissolving zinc (Scheme 9) <96HCA1475>. 

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