Review Article Number 138

Novel Taxa-4(20),12-diene and 2(3→20)Abeotaxane from Needles ofTaxus canadensis

“…[3][4][5][6] T. canadensis, an evergreen shrub distributed in North America, especially in the Quebec region of Canada, is one of the most extensively studied yews and more than 100 new taxanes have been reported. [7][8][9] As a continuation of our phytochemical study on T. canadensis, [10][11][12][13] we investigated the needles and isolated a new 6/8/6-membered taxane with a rare C-12(13)-double bond (1) and a new rearranged 2(3!20)abeotaxane (2) (Fig.…”

New Taxane Diterpenoids from the Roots of Taiwanese Taxus mairei.

“…A literature survey indicated that taxuspine K, isolated from Taxus cuspidata, and taxuyunnanine E, isolated from Taxus yunnanensis, are two analogues of 1. 3,[14][15][16] Detailed comparison of the proton and carbon resonances of H-5, C-5 (d 71.6), and C-4 (d 94.3) of 1 with those of taxuspine K and taxuyunnanine E revealed that the remaining acetyl and hydroxyl groups should be located at C-4 and C-5, respectively. Although these compounds had similar were markedly different from those of taxuyunnanine E. This led to the conclusion that the benzoyl moiety might be attached at C-15.…”

“…[1][2][3] Taiwan yew Taxus mairei is an evergreen shrub growing at high altitudes (2600 m) in the northern and central parts of Taiwan. Recent studies on the taxane diterpenoids of T. mairei have resulted in the isolation of taxumairols N and O from the roots, 4) and taxumairol R from the root bark, 5) taxumains A and B from the twigs, 6) taxumairol M and taxumairone A from the seeds, 7,8) 13-deacetylcanadensene and 7-deacetylcanadensene from the needles, 9) and taxumairols U-W from the stem bark.…”

7,8beta-dihydroponasterone A, a new phytoecdysteroid from the needles of the Japanese Yew, Taxus cuspidata

“…2 To date, more than 200 phytoecdysteroids were identified, 3,4 however, only four of them were isolated from the genus Taxus (yew trees). 5 The Japanese yew, Taxus cuspidata (Taxaceae), is a low trailing bush or tree very popular in Hokkaido and Tohoku regions, widely used as ornamental plant in Japan. Previous phytochemical studies on this species let to the isolation of taxanes with various skeleton, and other classes of compounds.…”