Quinine (1) has been known as the principal alkaloid in cinchona bark, which consists of various chemovars and hybrids of Cinchona species (Rubiaceae), such as C. ledgeriana, C. succirubra, C. calisaya, C. officinalis and others, grown and cultivated in tropical countries. A recent review...
calisaya), Colombian (C. lancifolia) or colorless (C. officinalis) (BMJ Publishing Group, 1924), each of which has a stable ratio of alkaloids. Plants with the yellow bark seem to be richer in quinine than those that have red or gray bark, the latter having the lowest compound ...