Artemisia annua, derivatives

Artemisinin, a tetracyclic 1,2,4-trioxane isolated from Artemisia annua L., is currently recommended as a first-line agent against Plasmodium falciparum malaria. Artemisinin and its synthetic derivatives have also been shown to be promising prototypes for the development of new antiproliferative agents. This chapter presents the recent advances on the analytic methods for extraction and quantification of artemisinin from A. annua plants as well as the biological properties of this natural product. 

Elsohly HN, Croom EM, Elsohly MA. (1987) Analysis of the antimalarial sesquiterpene artemisinin in Artemisia annua by high-perfomance liquid chromatography (HPLC) with postcolumm derivation and ultraviolet detection. Pharm Res 4 258-260. 

Nature has been a potential source of therapeutic agents for thousands of years. An impressive number of modem dmgs have been derived from natural sources. Over the last century, a number of top selling dmgs have been developed from natural products. Anticancer dmg vincristine from Vinca rosea, narcotic analgesic morphine from Papaver somniferum, antimalarial dmg artemisinin from Artemisia annua, anticancer dmg Taxol from Taxus brevifolia and antibiotic peniciUins from Penicillium ssp. are just a few examples. 

Artemisia annua and (—)-o -bisabolol from Matricaria recutita (German chamomile). Addition of IPP to GPP produces 2 , 6 -famesylpyropho-sphate (FPP), the precursor for all sesquiterpenes. Farnesylpyrophosphate can cyclize by various cyclase enzymes in various ways, leading to the production of a variety of sesquiterpenes. Some of these sesquiterpenes are medicinally important hioactive compounds. For example, (—)-o -bisabolol and its derivatives have potent anti-inflammatory and spasmolytic properties, and artemisinin is an antimalarial drug. 

Qinghao Artemisia annua (Asteraceae) Artemisinin and its derivatives... 

Sy, L. K. Brown, G. D. Haynes, R. A novel endoperoxide and related sesquiterpenes from Artemisia annua which are possibly derived from aUylic hydroperoxides. Tetrahedron, 1998, 54(17) 4345 356. 

Agrawal, P. K. Bishnoi, V. Studies on Indian medical plants. 42. Sterol and taraxastane derivatives from Artemisia annua and a rational approach based upon C-13 NMR for the identification of skeletal type of amorphane sesquiterpenoids. Indian J. Chem., 1996, 35B 86-88. 

Artesunate and artemether are soluble derivatives of artemisinin which is isolated from the leaves of the Chinese herb qinghao (Artemisia annua) they act against the blood, including sexual forms, of plasmodia and may also reduce transmissibility. Artesunate (i.v.) and artemether (i.m.) are rapidly... 

Artemisia annua, known in China as Qinghaosu, contains artemisinin, which has antimalarial activity. Several derivatives of the original compound have proved effective in the treatment of Plasmodium falciparum malaria and are currently available in a variety of formulations artesunate (intravenous, rectal, oral), artelinate (oral), artemisinin (intravenous, rectal, oral), dihydroartemisinin (oral), arte-mether (intravenous, oral, rectal), and artemotil (intravenous). Artemisinic acid (qinghao acid), the precursor of artemisin, is present in the plant in a concentration up to 10 times that of artemisinin. Several semisynthetic derivatives have been developed from dihydroartemisinin (11). The artemisinin derivatives are the subject of a separate monograph. 

Artemisinin, the principal bioactive antimalarial compound and its derivatives from Artemisia annua, a Traditional Chinese Medicinal plant used against fevers and malaria, have yielded a potent new class of antimalarials. The anti-malarials derived from A. annua are considered an integral part of the solution where malaria has become resistant to other medicines and even in areas where resistance is not yet a problem (S). Artemisinin-based combination therapies (ACTs) have been recommended in the countries where falciparam malaria - the most resistant form of the disease- is endemic (9). While ACTs for all would be the ideal strategy, it is most impractical for poor and remote communities, politically unstable areas, and people who dislike the use of modem medicine (10). 

Traditional Chinese Medicine gave rise to new plant-derived anticancer drugs as well as to therapeutics for the treatment of drug-resistant types of malaria tropica [70]. Artemisinin (Qinghaosu), the bioactive principle of Artemisia annua, was identified in 1972. Its unique structure was proven by X-ray analysis... 

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