Tree from the cinchona tree ("Cinchona") and was for a long time the remedy of choice for the treatment of malaria. Aspirin was synthesised to replace the sodium salicylate derived from the bark of willow trees ("Salix") which had unpleasant side effects. The anti-cancer drug Paclitaxel is derived from taxol, a substance found in the bark of the Pacific yew ("Taxus brevifolia"). Other tree based drugs come from the paw-paw ("Carica papaya"), the cassia ("Cassia spp."), the cocoa tree ("Theobroma cacao"), the tree of life ("Camptotheca acuminata") and the downy birch ("Betula pubescens"). The papery bark of the white birch tree
History of aspirin products such "Cafaspirin" (aspirin with caffeine) and "Alka-Seltzer" (a soluble mix of aspirin and bicarbonate of soda) put aspirin to new uses. In 1925, the German Bayer became part of IG Farben, a conglomerate of former dye companies; IG Farben's brands of "Aspirin" and, in Latin America, the caffeinated "Cafiaspirina" (co-managed with Sterling Products) competed with less expensive aspirins such as "Geniol". After World War II, with the IG Farben conglomerate dismantled because of its central role in the Nazi regime, Sterling Products bought half of Bayer Ltd, the British Bayer subsidiary—the other half of which it already owned. However,