Antimalarial

Antimalarial drugs are drugs that can kill malaria parasites or inhibit the reproduction of malaria parasites and are used to control malaria. As early as the first and second centuries AD, China's "Shen Nong's Herbal Classic" has recorded the anti-malaria of Changshan. The earliest application of the natural antimalarial drug quinine is an antimalarial ingredient in the bark of the cinchona used by Indians to treat fever, also known as cinchona cream. Rabe clarified its chemical structure in 1907. Later, he actively engaged in the research of synthetic antimalarial drugs. In 1926, Schulemann synthesized the first artificial antimalarial drug, plasmochin, also known as pamaquin-e. A atebrine, chloroquine, etc. have also appeared. In 1944 Woodward fully synthesized quinine successfully, confirming its structure. During the Second World War, primaquine, pentaquine, etc. were substituted for falciparum; and chlorpyrifos and pyrimethamine were synthesized according to the antagonism of biochemical metabolism. At the beginning of sixty years, the resistance of Plasmodium to chloroquine appeared, and it culminated in the search for new antimalarials. In foreign countries, due to the in-depth study of the structure-activity relationship of quinine, a new antimalarial drug of quinoline-methanols was developed, which is represented by mefloquine, and in China, from the study of 4-aminoquinoline drugs. Starting from the structure-activity relationship, a new antimalarial drug such as bisphenol (M6407), a pyridinium and pyronididine with a side chain of a bilateral tetrahydropyrrolemethylaminophenol and a quinolinol were synthesized. They are not only less toxic to the heart than chloroquine but also have varying degrees of antiarrhythmic effects. Chinese scientists have discovered Chinese herbal medicines such as Radix dichroa, Hydrangea umbellata, and Brucea javanica L. Merr. from Chinese herbal medicine. After testing, the chemical structure of Changshan, the active constituent of Changshan, was clarified. Artemisinin was isolated from Artemisia annua L., also known as Artemisia annua L. in the early 1970s. It was confirmed by animal experiments and clinical observation that its antimalarial effect is better than chloroquine and can be used to rescue dangerous malaria. As a result of chemical structure studies, it is a sesquiterpene containing a peroxy bridge, a new type that has not been seen in antimalarials. The sesquiterpene lactone of this peroxy bridge was completely synthesized in 1982. Chinese scholars have also discovered another anti-malarial component, octopus, containing the sesquiterpene of the peroxy bridge. Artemisinin and its derivatives also have significant anti-schistosomiasis effects. In addition, antibiotics lincomycins and tetracyclines also have antimalarial effects, but they are not used alone because of their slow action. Clindamycin and quinine can also be used to treat falciparum malaria.