Chloroquine is a 4-aminoquinoline

4-Aminoquinoline

4-Aminoquinoline is a form of aminoquinoline with the amino group at the 4-position of the quinoline.A variety of derivatives of 4-aminoquinoline are antimalarial agents useful in treating erythrocytic plasmodial infections. Examples include amodiaquine, chloroquine, and hydroxychloroquine....

 drug used in the treatment or prevention of malaria

Malaria

Malaria is a mosquito-borne infectious disease of humans and other animals caused by eukaryotic protists of the genus Plasmodium. The disease results from the multiplication of Plasmodium parasites within red blood cells, causing symptoms that typically include fever and headache, in severe cases...

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Chloroquine (CQ), N'-(7-chloroquinolin-4-yl)-N,N-diethyl-pentane-1,4-diamine, was discovered in 1934 by Hans Andersag and co-workers at the Bayer

Bayer

Bayer AG is a chemical and pharmaceutical company founded in Barmen , Germany in 1863. It is headquartered in Leverkusen, North Rhine-Westphalia, Germany and well known for its original brand of aspirin.-History:...

 laboratories who named it "Resochin". It was ignored for a decade because it was considered too toxic for human use. During World War II, United States government-sponsored clinical trials for anti-malarial drug development showed unequivocally that CQ has a significant therapeutic value as an anti-malarial drug.