Yew, Taxus

Taxine, C3,HgiOioN, is contained in the leaves, shoots and fruits of the yew (Taxus baccata), from which it was first isolated by Lucas. It was investigated by Marm, Hilger and Brande, Amato and Capparelli, Thorpe and Stubbs, Winterstein et al., Kondo et al., Takahashi and Gulland et al. ... 

Evergreens are the classic choice for clipped hedges, giving a solid backdrop of color and structure year-round. Yew (Taxus baccata) and boxwood (Buxus) make traditional hedges with a smooth finish boxwood is ideal for low hedges as it grows more slowly than yew. 

Taxol (Paclitaxel) 137, a natural product derived from the bark of the Pacific yew, Taxus brevifolia [213-215], and the hemisynthetic analogue Docetaxel (Taxotere) 138, two recent and promising antitumour agents, have been the matter of extensive in vivo and in vitro animal metabolic studies. The major metabolites of taxol excreted in rat bile [216] were identified as a C-4 hydroxylated derivative on the phenyl group of the acyl side chain at C-13 (139), another aromatic hydroxylation product at the mefa-position on the benzoate group at C-2 (140) and a C-13 deacylated metabolite (baccatin III, 142) the structure of six minor metabolites could not be determined. The major human liver microsomal metabolite, apparently different from those formed in rat [217], has been identified as the 6a-hydroxytaxol (141) [218, 219]. A very similar metabolic pattern was... 

Paclitaxel, from the bark of the pacific yew (Taxus brevifolia), inhibits disassembly of microtubules and induces atypical ones. Docetaxel is a semisynthetic derivative. 

Paclitaxel (21) was originally obtained from the bark of the Pacific yew, Taxus brevifolia Nutt. However, as the tree takes 200 years to mature, stripping the bark to produce this compound for the market was not sustainable. A better source of naturally occurring paclitaxel has not been found in other species and the total synthesis, on the other hand,... 

Stierle A, Strobel G, Stierle D, Grothaus P, Bignami G, The search for a taxol-producing microorganism among the endophytic fungi of the pacific yew, Taxus brevifolia, JNat Prod 58 1315-1324, 1995. 

Stierle A, Stierle D, Strobel G, Bignami G, Grothaus P, Endophytic fungi of pacific yew Taxus brevifolia) as a source of taxol, taxanes and other pharmacophores, in Bioregulators for Crop Protection and Pest Control, American Chemical Society, Washington DC, pp. 64—77, 1994. 

Pacific yew, Taxus brevifolia Nutt., Taxaceae, Gymn. 

The alkaloid ester paclitaxel (7.93) is a natural product derived from the western yew (Taxus brevifolia) and European yew (Taxus baccata). This agent functions as a mitotic spindle by causing excessive tubulin polymerization. Paclitaxel has demonstrated considerable clinical utility in ovarian and breast cancer. 

It is an alkaloid ester derived from the western yew Taxus brevifolia. 

Paclitaxel is an alkaloid ester derived from the Pacific yew (Taxus brevifolia) and the European yew (Taxus baccata). The drug functions as a mitotic spindle poison through high-affinity binding to microtubules with enhancement of tubulin polymerization. This promotion of microtubule assembly by paclitaxel occurs in the absence of microtubule-associated proteins and guanosine triphosphate and results in inhibition of mitosis and cell division. 

Some plant glycosides and polysaccharides cross-react195,197 with reagents for blood-group antigens, and interesting cross-reactions were also shown by methylated-fucose haptens and L-fucose-specific lectins for example, it was found that 2-O-methyl-L-fucose was immunodominant in the Japanese yew (Taxus cuspidata), and that the 3-0-... 

Cyclization reactions of GGPP mediated by car-bocation formation, plus the potential for Wagner -Meerwein rearrangements, will allow many structural variants of diterpenoids to be produced. The toxic principle taxine from common yew (Taxus baccata Taxaceae) has been shown to be a mixture of at least eleven compounds based on the taxadiene skeleton which can be readily rationalized as in Figure 5.43, employing the same mechanistic principles as seen with mono- and sesqui-terpenes. 

Shigemori H, Kobayashi J. Biological activity and chemistry of taxoids from the Japanese yew, Taxus cuspidate. J. Nat. Prod. 2004 67 245-256. 

Regarded as the tree of death by the Greeks and used to prepare arrow poison by the Celts, the yew tree has been associated with death and poisoning for centuries (68,69). The English yew, Taxus baccata was used to make funeral wreaths and it was believed that one could die by merely standing beneath the boughs of the tree. 

Male fern Dryopteris filix-mas Yew Taxus species... 

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