Structures of taxane diterpenoids from the seeds of japanese yew, Taxus cuspidata.

Taxane Diterpenoids from the Root Bark of Taiwanese Yew Taxus Mairei

“…7-e/»/-taxol (7), 14 taxol C, 10-deacetyltaxol C, 7ß-xylosyl-10-deacetyltaxol (8), 15 taxamairin A (9), 16 taxinine A, 17 14 ß-hydroxytaxusin, 18 5 α-hydroxy-7 ß,9a, 10 ß, 13 cx-tetraacetoxy-4(20),l 1-taxadiene, 1-dehydroxybaccatin-VI, 19 1 ß-dehydroxybaccatin-IV, 20 baccatin-IV, 20 (Table 1) revealed that they contained the same taxoid skeleton except for the cinnamoyl side chain at C-5 in 3 and an acetyl group in l. 11 Further on the basis of HSQC and HMBC analysis, the Ή and 13 C NMR data of 1 were assigned. This C-12(16)-oxido bridge was confirmed from the observation of cross-peaks from Me-18 and H2-I6 to C-ll and C-12 as well as correla tions between H-14 and C-12 in the HMBC spectrum (Fig.…”

“…This residue was ap plied on a Si gel column (700 g) and eluted with a solvent mix ture of CHCls/acetone to afford seven fractions, A (0.54 g), B (4.57 g), C (2.48 g), D (2.64 g), E (2.62 g), F (2.6 g) andG (8. 11 and taxumairol R (1, 6 mg). By using the same method, fraction B-4 yielded baccatin VI (7 mg) 19 and taxacin (4 mg), and fraction B-5 yielded baccatin IV (5 mg) 20 and frac tion B-6 gave 7-e/?/-deacetyltaxol (4 mg) and 7-e/?/-taxol (3 mg), 14 respectively.…”

Isolation and cytotoxicity evaluation of taxanes from the barks of Taxus wallichiana var. mairei

“…[9][10][11][12][13][14] In our screening program aimed at the discovery of structurally unique and biologically significant taxanes from Taxus plants, a new taxane glucoside, 7b,9a,10b-triacetoxy-13a-hydroxy-5a-O-(b-D-glucopyranosyl) taxa-4(20),11-diene (1), and 14 known analogues ( Fig. 1), 2-deacetoxytaxinine J 15 (2), 2-deacetoxyaustrospicatine 16 (3), cephalomannine 17 (4), 10-deacetyl-7-epi-taxol 18 (5), taxol 19 (6), 7-xylosyl-10-deacetyl taxol 20 (7), 7-b-xylosyl-cephalomannine 20 (8), 7-b-xylosyl-taxol 20 (9), 7-b-xylosyl-10-deacetyl-cephalomannine 20 (10), 7-xylosyl-10-deacetyl taxol C 20 (11), taxinine M 21 (12), taxacin 22 (13), 10-deacetylbaccatin III 23 (14), and baccatin III 17,20 (15) were isolated from the barks of T. wallichiana var. mairei.…”

A New Taxoid, 19-Acetoxytaxagifine, from Taxus chinensis

“…Paclitaxel (Taxol), which was isolated from Taxus brevifolia by Wani et al in 1971, has a unique mode of action and is used as an antitumor agent for treating breast and ovarian cancer . Early supply problems prompted extensive investigation of the constituents of various Taxus species, and many taxane diterpenoids have been isolated. − Several of these reports concentrated on the taxoid constituents of Taxus chinensis (Pilg.) Rehd (taxaceae), especially on novel tricyclo 5/7/6-membered ring compounds. − In our continuing studies of new antitumor agents from higher plants, we have also investigated the taxane diterpene constituents of T. chinensis var.…”