Deacetylation from Taxus baccata

Starting from needles of Taxus baccata (1 g 10-deacetyl baccatin III obtained from 1000 g dried needles). 

Early production of 1 kg of paditaxel required extraction from about 13,000kg of the Pacific yew tree bark. This process was refined, and pacli-taxel is now produced by a semisynthetic route. The starting material, 10-deacetyl baccatin 111 (10-DAB), is obtained from the needles of Taxus baccata (European yew) or T. wallichiana (Himalayan yew). The yield is around 1000 kg of needles to produce 1kg of 10-DAB. 

Paclitaxel and docetaxel are taxane plant alkaloids with antimitotic activity (see Table 124-12). Paclitaxel was isolated from the bark of the Pacific yew tree, Taxus brevifolia, but is now produced semisyntheti-cally from the needles of the European yew, Taxus baccata. Docetaxel is a semisynthetic taxoid extracted from 10-deacetyl baccatin III, a noncytotoxic precursor found in the renewable needle biomass of yew plants. ... 

Pacific yew (Taxus brevifolia) bark, the original source for this drug [92], has been supplemented with other yew sources such as bark, needles, and roots of T. media x Hicksii, T canadensis, and T. cuspidata. Semisynthesis of paclitaxel maybe accomphshed using baccatin HI or 10-deacetyl baccatin III from T. baccata, but full laboratory synthesis is too expensive for commercial uses. 

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