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5-<9- taxinine

Taxus cuspidata Sieb. et Zucc. T. chinensis (Pily) Rehd. T. yunnanensis Cheng et L. K. Fu Zhu Shan, Huang Dao Shan (Yew tree) (bark, leaf) Taxol, baccatin, cephalomannine, 10-deacetylbaccatin, yunnanxana, abeotaxanes, taxinine E.33 Antineoplastic, anticancer, treat ovarian carcinoma. [Pg.161]

Asymmetric IRDARs of optically active furfuryl fumarates 91 were investigated under thermal and high-pressure conditions. The diastereoselectivities observed increased with the size of the tether substituents, achieving up to 86% in the case of R = f-Bu, though in the case of R = neo-Pen only 38% de was obtained. It is concluded the diastereoselectivity observed was thermodynamically controlled (Scheme 27) [65]. An IRDA ring-expansion approach toward taxinine (a carbocylic compound) [66] utilizing both Lewis acids and high pressure has been reported [67]. [Pg.27]

Sometimes natural taxanes or synthetic taxoids exhibited unexpected cytotoxicities, which may provide new clues for SAR. Because m-azido baccatin 111 103 was found to be almost as comparably active as paclitaxel, 7-deoxy-9,10-O-acetylbac-catin 104 was prepared from taxinine 105, a plain and abundant inactive taxane from T. cuspidata. Both 104a and 104b were found to be inactive (IC50 at 10 M level). ... [Pg.105]

Horiguchi, T Oritani, T. Kiyota, H. Synthesis and antitumor activity of 2-(m-sub-stituted-benzyoyljbaccatin III analogues from taxinine. Tetrahedron, 2003, 59 1529-1538. [Pg.134]

Hosoyama, H. Shigemori, H. Tomida, A. Tsumo, T Kobayashi, J. Modulation of multidmg resistance in tumor cells by taxinine derivatives. Bioorg. Med. Chem. Lett., 1999, 9 389-392. [Pg.136]

Chapter 3), where novel skeletons and complex functionality make pre-Z-ray methods quite unsuitable. But the relatively ready access to Z-ray facilities is underlined by analyses (e.g. grayanotoxin-l, and taxinine ) undertaken to establish doubtful points of stereochemistry. [Pg.3]

Unfortunately, research work on taxines was hampered by their instability and the loss of activity upon storage because of the loss of dimethylamino moiety from the C-3 atom (Fig. 1) and the formation of corresponding cinnamates. Isolation of taxines is accomplished by alka-line/base extraction but it is difficult to obtain them in a purified form because of rapid acetate isomerization and/ or decomposition to taxinines. To the author s knowledge, there are no taxine/taxinine reference compounds commercially available. It is no surprise therefore that there are limited works that report on the high-performance liquid chromatography (HPLC) of taxines. Taxines were found in plant extracts interfering in extraction, isolation, and analysis of paclitaxel from plant material. ... [Pg.1579]

The author s work on the HPLC analysis of taxines was a follow-up of previous research work on the HPLC of taxanes. Unknown peaks present in the analysis of plant and cell culture extracts were suspected to be taxines. In previous works, several other researchers have reported the detection of impurity peaks in the extracts of Taxus X media (Hicksii) needles during the determination of taxanes. These uncharacterized impurities showed a UV maximum at 280 nm, with a A280/A228 ratio of approximately 3.5. Using absorbance ratio with these two or similar wavelengths, the researchers managed to overcome quantitation problems.Taxines and taxinines were also reported to cause problems in the HPLC analysis of taxanes, coeluting with the peak of paclitaxel. [Pg.1581]

The absolute configuration of the terpenoid core of taxine I was deduced by the X-ray analysis of the bromoderivative of a transformation product of its corresponding cinnamate (taxinine) [60], The L (1() absolute configuration of the dextrorotatory Winterstein acid obtained from the degradation of crude taxine was established by comparison with the rotatory power of the semisynthetic enantiomers prepared from D- and L P-phenyl-p-alanine [61]. [Pg.259]

Figure 19 Red-shifted chromophores and application to taxinine system. Figure 19 Red-shifted chromophores and application to taxinine system.

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