Taxane

Taxanes are poisonous alkaloids produced by Yew plants.
Alkaloids are natural basic chemical compounds which contain nitrogen atoms. The name comes from the word alkaline and was used to describe any alkaline containing nitrogen.
Alkaloids are made by a large variety of organisms, but taxanes are produced only by plants of the genus "Taxus".
Taxanes work mainly by disrupting the function of cell microtubules. Microtubules are essential to cell division, so taxanes are essentially mitotic inhibitors. This explains why taxanes have been used to produce chemotherapy drugs.