Pelletier, Pierre-Joseph (1788–1842)

French chemist whose extractions of a range of biologically active compounds from plants founded the chemistry of the alkaloids. The most important of his discoveries was quinine, used against malaria.

Pelletier was born in Paris and qualified as a pharmacist. He was professor at the Ecole de Pharmacie 1825–40.

Pelletier began with the analysis of gum resins and the colour pigments in plants. In 1817, together with chemist Joseph Caventou (1795–1877), he isolated the green pigment in leaves, which they named chlorophyll. In 1818 they turned to plant alkaloids: strychnine 1818, brucine and veratrine 1819, and quinine 1820. Their powerful effects made it possible to specify chemical compounds in pharmacology instead of the imprecise plant extracts and mixtures used previously.

Working with chemist Jean Baptiste Dumas, Pelletier obtained firm evidence for the presence of nitrogen in alkaloids 1823. He later carried out researches on strychnine and developed procedures for its extraction.

In 1832 Pelletier discovered a new opium alkaloid, narceine; he also claimed to have been the first to isolate thebaine (which he called paramorphine). In a study (1837–38) of an oily by-product of pine resin he discovered toluene (now methylbenzene).