Abstract The herb Artemisia annua has been used for many centuries in Chinese traditional
medicine as a treatment for fever and malaria. In 1971, Chinese chemists isolated from the
leafy portions of the plant the substance responsible for its reputed medicinal action. This ...

Background Artemisinin-based combination therapies are the recommended first-line
treatments of falciparum malaria in all countries with endemic disease. There are recent
concerns that the efficacy of such therapies has declined on the Thai–Cambodian border, ...

Summary Background On the western border of Thailand the efficacy of mefloquine in the
treatment of falciparum malaria has declined while gametocyte carriage rates have
increased, which suggests increased transmissibility of these resistant infections. We ...

To the Editor: Although artemisinins are potent and rapidly acting antimalarial drugs, their
widespread use for treating patients with Plasmodium falciparum malaria raises the question
of emerging drug resistance. 1, 2 Artemisinin monotherapy should not be used in areas ...

Artemisinin, a sesquiterpene lactone containing an endoperoxide bridge, has been isolated
from the aerial parts of Artemisia annua L. plants. It is effective against both drug-resistant
and cerebral malaria-causing strains of Plasmodium falciparum. The relatively low yield ( ...

The time course of the levels of artemisinin, its biosynthetic precursors and the
biosynthetically related sesquiterpenes was monitored during a vegetation period of
Artemisia annua plants of different geographical origin. Considerable differences in ...

Abstract Artemisinin and its derivatives have become essential components of antimalarial
treatment. These plant-derived peroxides are unique among antimalarial drugs in killing the
young intraerythrocytic malaria parasites, thereby preventing their development to more ...

Abstract Artemisinin (qinghaosu), is a promising new antimalarial drug derived from an
ancient Chinese herbal remedy. When [13-14 C] artemisinin is added to cultures of
Plasmodium falciparum, it is converted into a product with different solubility and ...

SUMMARY Artemisinin and its derivatives are endoperoxide-containing compounds which
represent a promising new class of antimalarial drugs. In the presence of intraparasitic iron,
these drugs are converted into free radicals and other electrophilic intermediates which ...

Artemisinin and its derivatives are widely used throughout the world. The mechanism of
action of these compounds appears to involve the heme-mediated decomposition of the
endoperoxide bridge to produce carbon-centred free radicals. The involvement of heme ...

Abstract [14 C] Artemisinin was taken up by Plasmodium falciparum in culture and
concentrated in hemozoin. In vitro, hemin and artemisinin were found to undergo a chemical
reaction forming two major products which were isolated by high-performance liquid ...

Background The Roll Back Malaria strategy recommends a combination of interventions for
malaria control. Zanzibar implemented artemisinin-based combination therapy (ACT) for
uncomplicated malaria in late 2003 and long-lasting insecticidal nets (LLINs) from early ...

BACKGROUND: Artemisinin-resistant falciparum malaria has arisen in western Cambodia.
A concerted international effort is underway to contain artemisinin-resistant Plasmodium
falciparum, but containment strategies are dependent on whether resistance has emerged ...

Abstract Artemisinin combination therapies are the first-line treatments for uncomplicated
Plasmodium falciparum malaria in most malaria-endemic countries. Recently, partial
artemisinin-resistant P. falciparum malaria has emerged on the Cambodia–Thailand ...

An important group of antimalarial drugs consists of the endoperoxide sesquiterpene
lactone artemisinin and its derivatives. Only little is known about the biosynthesis of
artemisinin in Artemisia annua L., particularly about the early enzymatic steps between ...

Currently, nearly two billion people are at risk of contracting malaria and the incidence of this
disease is dramatically increasing because many Plasmodium falciparum strains, the
parasite responsible for the majority of fatal malaria infections, have become resistant to ...

In order to investigate the possibility of isolating greater amounts of the antimalarial
compound artemisinin (quinghaosu), plants of ARTEMISIA ANNUA were cultivated and
analysed at different stages of development. We found the highest content just before ...

The herb, Artemisia annua L., a member of the Compositae family, has: been used for many
centuries in Chinese folk medicine. Ge Hong (1) in the year 340 and Li Shithen (2) in 1596
recommended the taking of an aqueous infusion of the plant to alleviate the chills and ...

4 tremely low antimalarial activity and cannot undergo the 1, 5-hydrogen atom transfer
depicted in Scheme 1, it is reduced by heme (generated via benzyl mercaptan reduction of
hemin) in tetrahydrofuran (THF) according to a previously proposed second mechanistic ...

Secondary metabolites from plants serve as defense against herbivores, microbes, viruses,
or competing plants. Many medicinal plants have pharmacological activities and may, thus,
be a source for novel treatment strategies. During the past 10 years, we have ...

Registration in Europe of several artemisinin drugs for the treatment of malaria can soon be
expected. Artemisinin is isolated from the herb Artemisia annua, in use in China more than
2000 years as a herbal tea against fever. Artemisinin drugs are being used extensively in ...

Artemisinin is a promising and a potent antimalarial drug, which meets the dual challenge
posed by drug-resistant parasites and rapid progression of malarial illness. This review
article focuses on the progress achieved during the last years in the production of ...

ABSTRACT Artemisinin is an important new antimalarial agent containing a bridged
endoperoxide. The in vitro antimalarial activity of an artemisinin derivative, arteether, is
antagonized by two iron chelators, pyridoxal benzoylhydrazone and 1, 2-dimethyl-3- ...

Abstract Artemisinin-based combination treatments (ACTs) are now generally accepted as
the best treatments for uncomplicated falciparum malaria. They are rapidly and reliably
effective. Efficacy is determined by the drug partnering the artemisinin derivative and, for ...

Abstract Artemisinin (qinghaosu) and its derivatives represent an important new class of
antimalarial drugs. Previous work suggests that the antimalarial activity of artemisinin may
be mediated by a reaction with intraparasitic hemin. Using cyclic voltammetry, artemisinin ...

Abstract Since 1979 several derivatives of artemisinin have been synthesized and studied in
China. Artemisinin suppositories, artesunate (oral or parenteral), intramuscular artemether
and dihydroartemisinin tablets have all proved rapidly effective. In all, 2352 patients (2150 ...

Artemisinin, a sesquiterpene lactone endoperoxide derived from the plant Artemisia annua,
forms the basis of the most important treatments of malaria in use today. In an effort to
elucidate the biosynthesis of artemisinin, an expressed sequence tag approach to ...

Summary Artemisinin and its derivatives are renowned for their potent antimalarial activity.
They have found their way into clinical use in many areas where malaria is endemic. The in
vitro concentration at which artemisinin can inhibit 50% of the growth of Plasmodium ...

A new method of microwave-assisted extraction (MAE) is used to extract artemisinin from
Artemisia annua L. Several solvents were used in MAE such as ethanol, trichloromethane,
cyclohexane, n-hexane, petroleum ether (30–60° C), petroleum ether (60–90° C), No. 120 ...

Artemisinin-type compounds are used for the treatment of uncomplicated and severe forms
of malaria. They reduce parasitaemia more rapidly than any other antimalarial compound
known, and are effective against multidrug-resistant parasites. However, uncertainties ...

Background: Artemisinin is a chemical compound extracted from the wormwood plant,
Artemisia annua L. It has been shown to selectively kill cancer cells in vitro and retard the
growth of implanted fibrosarcoma tumors in rats. In the present research, we investigated ...

Artemisinin derivatives artesunate (ART) and dihydroartemisinin are remarkable anti-
malarial drugs with low toxicity to humans. In the present investigation, we find they also
inhibited tumor cell growth and suppressed angiogenesis in vitro. The anti-cancer activity ...

(1 90" C) pyrolysis of artemisinin, Is is offered to account for these room-temperature results.
Iron (I1)-induced cleavage of the peroxide bond in trioxane 5c ieads to radical intermediates
10a and lob in about a 2: l ratio: CC bond cleavage of 1Oa initially produces labile ring- ...

Wiley Online Library. Medicinal Research ReviewsVolume 7, Issue
1, Article first published online: 18 SEP 2006. ...

Artemisinin and its derivatives are a potent new class of antimalarials, originated from
Artemisia annua, L. The clinical efficacy of these drugs is characterized by an almost
immediate onset and rapid reduction of parasitaemia. Their efficacy is high in such areas ...

Abstract. The sesquiterpenoid artemisinin, isolated from the plant Artemisia annua L., and its
semi-synthetic derivatives are a new and very effective group of antimalarial drugs. A branch
point in the biosynthesis of this compound is the cyclisation of the ubiquitous precursor ...

Artemisinin (qinghaosu), a sesquiterpenoid lactone peroxide constituent of annual
wormwood (Artemisia annua L.# ARTAN) that is used as an antimalarial drug, was tested for
phytotoxic properties. It inhibited germination of lettuce (Lactuca sativa L.) and annual ...

ABSTRACT.-A series of artemisinin-related endoperoxides was tested for cytotoxicity to
Ehrlich ascites tumor (EAT) cells using the microculture tetrazolium (MTT) assay. Artemisinin
E11 had an IC,, value of 29.8 kM. Derivatives of dihydroarremisinin [2], being developed ...

In 2010 there were more than 200 million cases of malaria, and at least 655,000 deaths 1.
The World Health Organization has recommended artemisinin-based combination therapies
(ACTs) for the treatment of uncomplicated malaria caused by the parasite Plasmodium ...

Abstract In prospective studies of acute uncomplicated, multidrug-resistant falciparum
malaria on the western border of Thailand, the oral artemisinin derivatives were used alone
in the treatment of 836 patients (artesunate 630, artemether 206), were combined with ...

Abstract Evolving resistance to artemisinin-based compounds threatens to derail attempts to
control malaria. Resistance has been confirmed in western Cambodia and has recently
emerged in western Thailand, but is absent from neighboring Laos. Artemisinin resistance ...

In the first part of this account, the antimalarial drug artemisinin is presented, and the current
hypotheses on the mechanism of action of this endoperoxide-based drug are reviewed. The
alkylating ability of artemisinin and synthetic analogues toward heme related to their ...

Artemisinin-based combination therapies (ACTs) are the best anti-malarial drugs available
now. Artemisinin enhances efficacy and has the potential of lowering the rate at which
resistance emerges and spreads. Under low transmission intensity, ACTs have an ...

Summary The emergence and spread of multidrug resistant Plasmodium falciparum has
severely limited the therapeutic options for the treatment of malaria. With ever-increasing
failure rates associated with chloroquine or sulphadoxine-pyrimethamine treatment, ...

Abstract Endoperoxide antimalarials based on the ancient Chinese drug Qinghaosu
(artemisinin) are currently our major hope in the fight against drug-resistant malaria.
Rational drug design based on artemisinin and its analogues is slow as the mechanism of ...

Abstract Artemisinin is a plant natural product produced by Artemisia annua and the active
ingredient in the most effective treatment for malaria. Efforts to eradicate malaria are
increasing demand for an affordable, high-quality, robust supply of artemisinin. We ...

Abstract The global dissemination of drug-resistant Plasmodium falciparum is spurring
intense efforts to implement artemisinin (ART)–based combination therapies for malaria,
including mefloquine (MFQ)–artesunate and lumefantrine (LUM)–artemether. Clinical ...

Abstract Artemisinin and its derivatives are important new antimalarial drugs. When
Plasmodium falciparum-infected erythrocytes are incubated with [10-3 H] dihydroartemisinin,
several malaria-specific proteins become labeled. One of these proteins is the P. ...

Although chloroquine-resistance (CQR) in Plasmodium falciparum is increasing and
resistance to other blood schizonticidal anti-malarials has been reported, the molecular
basis remains unclear. In this study fresh field isolates were obtained from The Gambia, ...

Secondary metabolites from plants can serve as defense against herbivores, microbes,
viruses or competing plants. Many compounds from medicinal plants have pharmacological
activities and thus may be a source for novel antitumor agents. We have analyzed natural ...

Abstract Plasmodium falciparum resistance to chloroquine and sulphadoxine–
pyrimethamine has led to the recent adoption of artemisinin-based combination therapies
(ACTs) as the first line of treatment against malaria. ACTs comprise semisynthetic ...

In plants, sesquiterpenes of different structural types are biosynthesized from the isoprenoid
intermediate farnesyl diphosphate. The initial reaction of the biosynthesis is catalyzed by
sesquiterpene cyclases (synthases). In Artemisia annua L.(annual wormwood), a number ...

The tissue localization of the antimalarial sesquiterpenoid compound artemisinin in annual
wormwood (Artemisia annua L.) was determined by differential extraction of a glanded
biotype and through the use of a glandless biotype. A 5-s dip in chloroform extracted 97% ...

Abstract: A 10-step stereoselective total synthesis of the antimalarial cadinane
sesquiterpene (+)-artemisinin (1) is described. Elaboration of (R)-(+)-pulegone to the known
sulfoxide 11 was followed by dianion alkylation and desulfurization to provide the trans-2, ...

The photooxidation of artemisinic (arteannuic) acid {l], has been studied by several groups
(1-3) in a search for a route from this relatively abundant constituent of Artemisia annua to
the antimalarial drug artemisinin 137 (qinghaosu) which is present in the same plant in ...

Among the 300-500 million people worldwide who are currently infected with malaria, about
2 million deaths, many of them children, occur each year.'As malaria parasites develop ever-
increasing multidrug resistance to traditional alkaloidal antimalarial drugs? artemisinin ( ...

Abstract: Despite international efforts to 'roll back malaria'the 2008 World Malaria Report
revealed the disease still affects approximately 3 billion people in 109 countries; 45 within
the WHO African region. The latest report however does provide some 'cautious optimism'; ...

This study was designed to determine the pharmacokinetic parameters of a new
pharmaceutical form of artemisinin (a natural substance extracted from the Artemisia annua
L. plant) and of one of its derivatives, artesunate, a semisuccinate of 12-hydroxy- ...

Malaria remains a major global health problem, killing about one million people each year,
with the protozoan parasite Plasmodium falciparum responsible for this most deadly illness.
The sesquiterpene endoperoxide artemisinin is currently the most effective treatment ...

The endoperoxide sesquiterpene lactone artemisinin and its derivatives are a promising
new group of drugs against malaria. Artemisinin is a constituent of the annual herb Artemisia
annua L. So far only the later steps in artemisinin biosynthesis—from artemisinic acid— ...

To the Editor: Artemisinin-based combination therapies have recently been introduced in
virtually all countries in which malaria is endemic, thereby making such drugs the most
essential class of antimalarial agents. The spread of artemisinin resistance could have a ...

Abstract Artemisinins, derived from the wormwood herb Artemisia annua, are the most
potent antimalarial drugs currently available. Despite extensive research, the exact mode of
action of artemisinins has not been established. Here we use yeast, Saccharamyces ...

Plasmodium falciparum resistance to artemisinin derivatives in southeast Asia threatens
malaria control and elimination activities worldwide. To monitor the spread of artemisinin
resistance, a molecular marker is urgently needed. Here, using whole-genome ...

Abstract Reliable and reproducible methods for the measurement of artemisinin and its
derivatives in body fluids have proved difficult to develop. The available evidence suggests
that all compounds are hydrolysed to a biologically active metabolite, dihydroartemisinin, ...

The alkylation of a synthetic metalloporphyrin heme model, manganese(II)
tetraphenylporphyrin, by artemisinin,8 artemether, and other synthetic pharmacologically active
trioxanes9 has been reported in recent years. Herein, the “true” target of artemisinin, ...

Cuttings of a clone of A. annua L.(Asteraceae), grown under 16 h photoperiod for 55 days
were transferred to six photoperiod treatments in the greenhouse. Under short photoperiods
(8, 10, or 12 h), plants flowered after two weeks; plants under long photoperiods (16, 20, ...

The preliminary results of a clinical safety review that partly used the Cochrane methodology
are presented. Despite methodological limitations including incomplete databases, this
review collated evidence corroborating the benign safety profile of the artemisinin type of ...

BACKGROUND: The burden of Plasmodium vivax infections has been underappreciated,
especially in southeast Asia where chloroquine resistant strains have emerged. Our aim was
to compare the safety and efficacy of dihydroartemisinin-piperaquine with that of ...

Artemisinin, a compound isolated from the sweet wormwood Artemisia annua L., has
previously been shown to have selective toxicity towards cancer cells in vitro. In the present
experiment, we studied the potential of artemisinin to prevent breast cancer development ...

Abstract The emergence and spread of multidrug-resistant Plasmodium falciparum
compromises the treatment of malaria, especially during pregnancy, where the choice of
antimalarials is already limited. Artesunate (n= 528) or artemether (n= 11) was used to ...

Abstract Malaria, caused by Plasmodium sp, results in almost one million deaths and over
200 million new infections annually. The World Health Organization has recommended that
artemisinin-based combination therapies be used for treatment of malaria. Artemisinin is a ...

ABSTRACT Resistance of Plasmodium falciparum to drugs such as chloroquine and
sulfadoxine-pyrimethamine is a major problem in malaria control. Artemisinin (ART)
derivatives, particularly in combination with other drugs, are thus increasingly used to treat ...