Quinine

Quinine is an alkaloid found in the bark of the cinchona tree. Quinine has been used to treat malaria (a recurring disease marked by severe chills and fever) since the early 1600s. It was the best chemotherapeutic (chemical therapeutic) agent available to combat the disease until the 1920s. Malaria treatment by quinine marked the first successful use of a chemical compound to treat an infectious disease.

The Discovery of Quinine

Quinine has been referred to as "Jesuits' bark," "cardinal's bark," and "sacred bark." Its name stems from its use in 1630 by Jesuit missionaries in the Andes (a mountain range in western South America). A legend suggests earlier use by the native population. According to the legend, an Indian with a high fever was lost in an Andean jungle. When he drank from a pool of stagnant (standing) water, he found it tasted bitter. Realizing it had been contaminated by the surrounding quina-quina trees he thought he was poisoned. But his fever abated, and thereafter his village used extracts made from quina-quina bark to treat fevers.

The legend of quinine's discovery accepted in Europe involves the Countess of Chinchon, who had visited Peru. While in Peru the countess contracted a fever which was cured by the bark of a tree. Returning to Spain with the bark, she introduced quinine to Europe in 1638. In 1742 Swedish botanist Carol Linnaeus (1707-1778) called the tree "Cinchona" in her honor. The legend is a bit faulty. In fact, the Countess never had malaria and died in Colombia before reaching Spain.

Synthesizing Quinine

Malaria is a lethal disease worldwide. Because it is so widespread, the potential value of quinine inspired research into its synthesis. In 1820 French chemist Pierre-Joseph Pelletier (1788-1842) and Joseph-Bienaime Caventou (1795-1877) isolated quinine from cinchona bark. In 1908, P. Rabe theorized the correct chemical structure of quinine. This structure was not confirmed, however, until 1944 when American chemist Robert Burns Woodward (1917-1989; 1965 Nobel Prize winner in chemistry) and William von Eggers Doering first successfully synthesized the chemical. This was an amazing achievement of synthetic organic chemistry, but of little commercial value as the cost of the process was too high to be practical.

In the beginning of the twentieth century most of the naturally produced quinine originated in Java, now part of Indonesia. During World War I (1914-1918), Germany was cut off from supplies of quinine and developed the synthetic substitute Atabrine. By 1942 when the United States entered World War II (1939-1945), the Javanese plantations were controlled by Japan. American soldiers fighting in North Africa and the South Pacific islands were devastated by malaria. White pills taken from captured Italian soldiers were sent back to the United States. They were found to be the synthetic antimalarial drug chloroquine. The drug was manufactured by the same German lab as Atabrine. The United States was then able to synthesize several tons of its own before the end of the war.

Today, both chloroquine and Atabrine are used to prevent malaria. There are areas of the world, however, where malaria parasites have developed a resistance to synthetic drugs. Vietnam is one of those areas. For those cases, quinine is still effective in malaria treatment.