Artemether - CAS 71963-77-4

Description

Artemether is an antimalarial for the treatment of multiple drug-resistant strains of Plasmodium falciparum malaria.

Synonyms

3,12-epoxy-12h-pyrano(4,3-j)-1,2-benzodioxepin,decahydro-10-methoxy-3,6,9-trim; 5a-beta,6-beta,8a-beta,9-alpha,12-beta,12ar)-(3-alph(+)-ethyl; artemisininelactolmethylether; cgp56696; dihydroartemisininmethylether; dihydroquinghaosumethylether; methyl-dihydroartemisinine; [3r-(3r,5as,6s,8as,9r,10r,12s,12ar**)]-decahydro-10-methoxy-3,6,9-trimethyl-3,12-epoxy-12h-pyrano[4,3-j]-1,2-benzodioxepin

IUPAC Name

(1R,4S,5R,8S,9R,10S,12R,13R)-10-methoxy-1,5,9-trimethyl-11,14,15,16-tetraoxatetracyclo[10.3.1.04,13.08,13]hexadecane

Canonical SMILES

CC1CCC2C(C(OC3C24C1CCC(O3)(OO4)C)OC)C

InChI

InChI=1S/C16H26O5/c1-9-5-6-12-10(2)13(17-4)18-14-16(12)11(9)7-8-15(3,19-14)20-21-16/h9-14H,5-8H2,1-4H3/t9-,10-,11+,12+,13+,14-,15?,16-/m1/s1

InChIKey

SXYIRMFQILZOAM-GXTLMGRASA-N

Solubility

DMSO: =20 mg/ml

Melting Point

89 ºC

Optical Rotation

Specific optical rotation = 177 deg at 19.5 °C

LogP

3.53

Vapour Pressure

4X10-5 mm Hg at 25 °C (est)

Mechanism Of Action

Involves an interaction with ferriprotoporphyrin IX ("heme"), or ferrous ions, in the acidic parasite food vacuole, which results in the generation of cytotoxic radical species. The generally accepted mechanism of action of peroxide antimalarials involves interaction of the peroxide-containing drug with heme, a hemoglobin degradation byproduct, derived from proteolysis of hemoglobin. This interaction is believed to result in the formation of a range of potentially toxic oxygen and carbon-centered radicals.

Pharmacology

In the body, artemether is metabolized into the active metabolite metabolite dihydroartemisinin. The drug works against the erythrocytic stages of P. falciparum by inhibiting nucleic acid and protein synthesis. Artemether is administered in combination with lumefantrine for improved efficacy. Artemether has a rapid onset of action and is rapidly cleared from the body. It is thought that artemether provides rapid symptomatic relief by reducing the number of malarial parasites. Lumefantrine has a much longer half life and is believed to clear residual parasites.

Toxicity (LD50)

Animal studies on acute toxicity show that the LD50 of Artemether in mice is a single i.g. administration of 895mg/kg and a single i.m. injection of 296mg/kg dose; in rats, the LD50 is a single i.m. injection of 597mg/kg dose.

In Vitro

In the in vitro blood distribution studies, the content ratios from blood cells to plasma were compared in the concentrations from 20 ng/mL to 1000 ng/mL. Such ratios were determined to be 1.1-1.6 for artemisinin, 0.9-1.2 for artemether, and around 0.7 for dihydroartemisinin. Referring to the in vitro distribution, the AUC(0-t) ratios from the blood cells measurements to the plasma measurements of these three antimalarial drugs were also in a similar trend as the in vitro distribution measurements. Furthermore, the half-life (t1/2) of artemether in blood cells was even longer than that in plasma, while the clearance of artemisinin, artemether, or dihydroartemisinin in blood cells was slower than that in plasma. Particularly, it was found that the concentrations of artemisinin and artemether were presented in blood cells over longer time period than in plasma above their antimalarial IC50, which might result from both the affinity toward blood cells and the drugs clearance differences between blood cells and plasma.

In Vivo

In the oral administration pharmacokinetic studies in rats, the concentration ratios from blood cells to plasma were from high (2.6-3.6) to medium (1.3-2.5), and low (0.5-1.5) for artemisinin, artemether, and dihydroartemisinin respectively in all measuring time points, displaying the similar affinity order toward blood cells in artemisinin > artemether > dihydroartemisinin as the in vitro measurements. The dosages of 10 mg/kg for intravenous administrations of artemisinin and 200 mg/kg for oral administrations of artemisinin or artemether were used for the pharmacokinetic study in rats. The geometric mean exposures (AUC(0-t)) of artemisinin, artemether and dihydroartemisinin in blood cells were determined to be 2.6 folds, 1.7 folds, or 1.2 folds greater than those in plasma, respectively. Artemether significantly suppressed pro-inflammatory mediators (NO/iNOS, PGE2/COX-2/mPGES-1, tumour necrosis factor-alpha (TNFα) and interleukin (IL)-6); Aβ and BACE-1 in BV2 cells following LPS stimulation. These effects of artemether were shown to be mediated through inhibition of NF-κB and p38 MAPK signalling. Artemether produced increased levels of HO-1, NQO1 and GSH in BV2 microglia. The drug activated Nrf2 activity by increasing nuclear translocation of Nrf2 and its binding to antioxidant response elements in BV2 cells. Transfection of BV2 microglia with Nrf2 siRNA resulted in the loss of both anti-inflammatory and neuroprotective activities of artemether.

Clinical Trial Information

Application

ADCs Cytotoxin

Appearance

White to Off-White Solid

Purity

>99%

Quantity

Milligrams-Grams-Kilograms

Quality Standard

Enterprise Standard

Shipping

-20°C (International: -20°C)

Storage

Providing storage is as stated on the product vial and the vial is kept tightly sealed, the product can be stored for up to 24 months(2-8C).

Pictograms

Irritant

Signal Word

Warning