Chemistry Reference
In-Depth Information
O
O
O
O
O
O
H
H
O
O
O
OR
N2
Artemether, R
=
CH
3
N3
Arteether, R
=
CH
2
CH
3
N4
Sodium artesunate,
R
=
COCH
2
CH
2
COONa
N1
Artemisinin
O
O
O
NH
2
NH
O
N5
OZ-277 (RBx11160)
Figure 14.14
Structures of artemisinin and related compounds.
and malaria. Artemisinin (
N1
) (Qing Hao Su) (128), the active principle, directly
kills
Plasmodium falciparum
(malaria parasites) with little toxicity to animals
and humans. Thus, it is a clinically effective, safe, and rapid antimalarial agent
(129, 130). The novel endo-peroxide link is essential for the antimalarial activity.
Artemether (
N2
) and arteether (
N3
) are the most well-studied analogs among
many synthetic derivatives and are used in malaria-prone regions, particularly
India (131). Artemether and sodium artesunate (a hemisuccinate derivative of
dihydroartemisinin) (
N4
) have been added by the World Health Organization to
its Model List of Essential Medicines (132).
The laboratory of the authors has synthesized analogs related to artemisinin
(133). Recently, an antimalarial synthetic trioxolane drug development candidate
called
OZ-277
(
N5
, also known as RBx11160) (134) has sparked great interest
and has progressed to Phase II clinical trials in India, Thailand, and Africa. Mod-
ification and pharmacological studies are ongoing (135-137). A recent review
discusses artemisinin and related antimalarials (138).
14.3.2 Ginsengs: Asian, American, Sanchi, and Siberian
Ginseng is the root of
Panax ginseng
C.A. Meyer (Asian ginseng) (Araliaceae
family). In Oriental medicine, it has enjoyed a strong reputation since ancient
times for being tonic, regenerating, and rejuvenating. The genus name
Panax
is
formed from the Greek pan (all) and akos (remedy). This panacea (panakeia) was
believed to be the universal remedy. Wild ginseng is scarce and has been replaced
