Cadinane sesquiterpene

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... 

An unusual related molecule, named hydroperoxycadiforin, Fig. (6), with the combined structure of a cadinan sesquiterpene and hyperforin, containing a hydroperoxide moiety, has been isolated from the stems and leaves of II. perforatum [49]. 

Artemisinin (44) is a structurally complex cadinane sesquiterpene lactone bearing an endoperoxide group embedded in a 1,2,4-trioxane ring. With its unique juxtaposition of peracetal, acetal and lactone functionalities, it has very much to interest organic chemists. Totally synthetic routes to artemisinin have been developed [64], but their complexity suggests that they will very unlikely supplant the natural extract as drug source. 

An alternate route to the serrulatanes involves formation of a macrocyclic intermediate (a germacrene isoprenologue) analogous to that implicated in the biosynthesis of the cadinane sesquiterpenes (91). 

Novel Fish Toxins of the Cadinane Sesquiterpene Class... 

Miles (8) et ii. later reported the isolation of two additional novel cadinane sesquiterpenes with the same basic skeleton as heritol (I) from the hexane extract. These compounds were assigned the names heritonin GH) and heritianin (IV). 

In 1987, Chittawong (10) reported, from the aqueous extract, the isolation and identification of a fourth novel cadinane sesquiterpene with the same basic skeleton as... 

Artemisia annua is one of the most important Asteraceae species as antimalarial plant. There are many reports of microbial biotransformation of artemisinin (283), which is active antimalarial rearranged cadinane sesquiterpene endoperoxide, and its derivatives to give novel antimalarials with increased activities or differing pharmacological characteristics. 

In his synthesis of the cadinane-sesquiterpene veticadinol (69), Lutz Tietze employed a sequence of Knoevenagel condensation of (i )-citronellal (66) and dimethylmalonate followed by an ene reaction provide 68 with the requisite trans stereochemistry in what was to become the decalin core of veticadinol 69. ... 

The rearrangement of 6/5-fused dienones has also been apphed to the synthesis of natural products. The 6P-isopropyl derivative of acetoxy ketone 45, obtained upon irradiation of the 6P-isopropyl derivative of dienone 44, was used in the synthesis of oplopanone. On the other hand, expansion of the A ring in the 5/6-fused methoxy ketone resulting from irradiation of the 6P-isopropyl derivative of le, allowed the synthesis of the cadinane sesquiterpene 3-oxo-a-cadinol and a-cadinoL ... 

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