­^ ¤å ºK ­n Nearly 400 taxane diterpenoids have been isolated and identified¡C Taxol is a diterpene amide natural product isolated from Taxus brevifolia. The clinical formulation of Taxol has received US FDA approval for treatment of chemotherapy refractory metastatic breast and ovarian cancers, and the drug has shown activity against other cancers in clinical trials. In order to discover new taxoid derivatives, the twigs and leaves of the Formosan Taxus sumatrana (Miq) de Laub. growing in the forest of Kaohsiung Liukuei area was collected for phytochemical and anti-tumor investigation. This investigation has resulted in the isolation of nineteen taxoids, which were identified as tasumatrol H (1)¡Btasumatrol I (2)¡Btasumatrol J (3)¡Btasumatrol K (4)¡Btasumatrol L (5)¡B10-deacetyl- 13-oxo baccatin III (6) ¡B 10- deacetyl baccatin III (7) 20-acetoxy-2£\-benzyloxy-4£\,5£\,7£\,9£\,13£\-pentahydroxy-11(15-1)11(10-9)bisabeotax-11-eno-10,15- lactone (8) ¡B5£\-hydroxy-2£\,7£],9£\,10£],13£\-tetraacetoxy 4(20) 11¡Vtaxadine (9)¡Btaxuspine F (10) ¡Bbaccatin IV (11)¡Bwalifoliol (12)¡B20-deacetyl texachitriene A (13)¡Btaxinin M (14)¡B7-epi-10 deacetyl taxol (15)¡BTaxol (16)¡Bbaccatin III (17)¡Btaxacin (18) ¡Byunnanxane (19).Among them, compounds 1¡B2¡B3¡B4¡B5 are new compounds from natural source. All structures were established primarily on the basis of 1D and 2D NMR techniques, including DEPT, COSY, HMBC and NOESY experiments. Tasumatrols I¡BJ and K (2-4) exhibited cytotoxicities against human Hepa59T/VGH¡BNCI¡BHela¡BDLD-1 and Med tumor cell lines.

Taxol is a complex polyoxygenated diterpene isolated from Pacific yew (Taxus brevifolia). The structures of Taxoids are diversified with species, season and growth environment and the clinical effectiveness of Taxol as a microtubule-stabilizing therapeutic agent for treatment of several malignancies has motivated many scientists to isolate new taxoids and investigate their anti-tumor activities. In this continuing search for new and bioactive natural taxoids, reinvestigation of the acetone extract of the twigs, needles and branches of Taxus sumatrana (Taxaceae) afforded thirty-seven taxane diterpenes esters, including sumataxins sumataxin A (1)¡Bsumataxin B (2)¡Bsumataxin C (3)¡Bsumataxin D (4)¡Btaxuyunnanine C (5)¡B5a,7B,9a,10B,13a-petaacetoxy-4(20),11-taxadiene (6)¡B2a,5a,9a,10B,14B-pentaacetoxytaxa-4(20),11-taxadiene (7)¡B14B-hydroxytaxusin (8)¡B2a-deacetoxytaxinine J (9)¡Btaxa-4-(20),11-diene-2a,5a,7B,9a,10B,13a-hexaol hexaacetate (10)¡B1-dehydroxy baccatin VI (11)¡B7B,9a,10B,13a,20-pentaacetoxy-2a-benzoyloxy-4a,5a-dihydroxytax-11-ene (12)¡Btaxacin (13)¡Bbaccatin VI (14)¡Btaxuspinanane J (15)¡B2-deacetoxy-5-decinnamoyltaxinine J (16)¡BN-Methyl taxol C (17)¡B10-deacetyl yunnanaxane (18)¡Btaxumairol B (19)¡Btaxinine M (20)¡Bbaccatin III (21)¡Btaxuspinanane I (22)¡Btaxumairol K (23)¡Bwallifoliol (24)¡B13-oxo-baccatin III (25)¡Btaxol (26)¡B7-epi-10-deacetyl taxol (27)¡B10-deacetyl-13-oxo-baccatin III (28)¡B19-hydroxybaccatin III (29)¡B10-deacetyl taxol (30)¡B10-deacetyl-baccatin III (31)¡B13-acetyl-13-decinamoyltaxachinin B (32)¡B5-deacetyltaxachitriene B (33)¡B5-epicanadensene (34)¡Btaxezopidine F (35)¡B13a,7B-diacetoxy-2a,5a,10B-trihydroxy-9-keto-2(3¡÷20)abeotaxane (36)¡B2-deacetyl taxine B (37). The structures of new compounds were established on the basis of their spectroscopic analyses. Among them, compounds 1, 2, 3 and 4 are new compounds from natural source, 2a-deacetoxytaxinine J (9)¡Btaxuspinanane J (15) had effects on PBMC (Peripheral Blood Mononuclear Cells) proliferation, and sumataxin A¡BD (1¡B4) had light exhibitedactivity of HSV-1.

In recent years, many marine invertebrates were studied in the world, and many compounds were discovered from soft corals (for example: sesquiterpenoids, diterpenoids, steroids and so on). From the previous studies on marine nature products, we found that verticillenes of soft corals have similar structures to taxoid diterpenoids of Taxus sp. This prompted us to study Taxus sp., thus we may indirectly understand the correlation of verticillienes of Taxus with verticilliene diterpenes of the soft corals. In order to discover new taxoid derivatives, the twigs and leaves of the Formosan T. sumatrana growing in Taiwan were investigated. Chromatographic separations of acetone extract of the leaves and twigs of this species yielded taxoid-enrich extracts. Fractionation of T. sumatrana has resulted in the isolation of four new compounds 1- 4. All structures were established primarily on the basis of 1D and 2D NMR experiments and other physical methods, such as mass spectroscopy, infrared, ultraviolet and optical rotation. The compound 1 is a taxoid 6/10/6 ring skeleton. The compounds, 2~4, are the verticillene skeleton, but the functional groups are different.

Abstract In recent years, Taxus species have attracted a great interest because Paclitaxel, an anticancer agent, was isolated from T.brevifolia. Since the discovery of Paclitaxel many new taxane diterpenes from various Taxus species were isolated. In order to discover new taxoids, twigs and leaves of Taxus sumatrana (Miq.) de Laub. Growing in Taiwan were employed. Chromatographic separation of acetone extract of the leaves and twigs of the plant has yielded four taxane diterpenes and one derivative, designated tasumatrol M (1), tasumatrol N (2), tasumatrol O (3) and 7-deacetyl-canadensene (4). All structures were established primarily on the basis of 1D and 2D NMR techniques, including DEPT, COSY, HMBC and NOESY experiments. Compound 1, 2 and 3 were inactive as tested against human KB, Hepa59T, Hela, DLD-1 and WiDr tumor cell lines. Compounds 1 and 2, possessing a bicyclic skeleton, together with compounds 3 were new compounds from natural source. The possible biosynthetic pathway of compounds 1 and 2 were derived from geranylgeranyl pyrophosphate and verticillene.