New taxanes from the needles of Taxus canadensis

Ten new taxanes were isolated from the methanol extract of the needles of the Canadian yew, Taxus canadensis. On the basis of their spectral analysis, their structures were established as 9alpha-hydroxy-2alpha,7alpha,10beta-triacetoxy-5alpha-cinnamoyloxy-3,11-cyclotaxa-4(20)-en-13-one (1), 9alpha,10beta-diacetoxy-5alpha-cinnamoyloxy-3,11-cyclotaxa-4(20)-en-13-one (2), 9alpha,20-dihydroxy-2alpha,10beta,13alpha-triacetoxytaxa-4(5),11(12)-diene (3), 2alpha,9alpha,10beta-triacetoxy-20-cinnamoyloxy-11,12-epoxytaxa-4-en-13-one (4), 9alpha-hydroxy-2alpha,10beta,13alpha-triacetoxy-5alpha-(3'-methylamino-3'-phenyl)-propionyloxytaxa-4(20),11-diene (5), 2alpha,10beta-diacetoxy-5alpha,9alpha-dihydroxytaxa-4(20),11-dien-13-one (6), 2alpha,9alpha-diacetoxy-5alpha,10beta-dihydroxytaxa-4(20),11-dien-13-one (7), 5alpha,9alpha-dihydroxy-2alpha,10beta,13alpha-triacetoxytaxa-4(20),11-diene (8), 5alpha,10beta-dihydroxy-2alpha,9alpha,13alpha-triacetoxytaxa-4(20),11-diene (9), and 7beta,11beta-dihydroxy-2alpha,9alpha,10beta,13-tetraacetoxy-5alpha-cinnamoyloxytaxa-4(20),12-diene (10). Taxane 1 is the first example of a 3,11-cyclotaxane with a 7-epi-alpha-oxygenated group. Taxane 4 is the first taxane with a C-11,12-epoxide ring as well as a C-4(5)-endo-double bond. Taxanes with a 12(13) double bond as in 10 instead of the usual 11(12) double bond have been found so far only in the needles, stem, and seeds of the Japanese yew.     

Taxane diterpenoids from the stem bark of Taxus mairei

Three new 11(15-->1)-abeo-taxanes, taxumairols U-W (1-3), have been isolated from extracts of the stem bark of Formosan Taxus mairei. The structures of 1-3 were identified as 5alpha,7beta,9alpha,13alpha,20-pentaacetoxy-2alpha,10beta,15-trihydroxy-11(15-->1)-abeo-taxene, 5alpha,7beta,9alpha,20-tetraacetoxy-2alpha,10beta,13alpha,15-tetrahydroxy-11(15-->1)-abeo-taxene, and 2alpha,4alpha,7beta,10beta-tetraacetoxy-5beta,20-epoxy-9alpha,13alpha,15-trihydroxy-11(15-->1)-abeo-taxene, respectively, on the basis of 2D NMR techniques including COSY, HSQC, HMBC, and NOESY experiments as well as chemical reactions of compounds 1-3 to give 4 (5alpha,7beta,9alpha,10beta,13alpha,20-hexaacetoxy-2alpha,15-dihydroxy-11(15-->1)-abeo-taxene) and 5 (4alpha,7beta,10beta-triacetoxy-9alpha,13alpha-dibenzoxy-5beta,20-epoxy-2alpha,15-dihydroxy-11(15-->1)-abeo-taxene), which are also novel taxane derivatives. Taxumairols U (1) and V (2) exhibited significant cytotoxicities against human hepatoma tumor cells, while taxumairol W (3) was inactive.     

Taxoids and abietanes from callus cultures of Taxus cuspidata

Seventeen known taxoids and 10 abietanes were isolated from the dark brown callus culture of Taxus cuspidata cultivated on a modified Gamborg's B5 medium with 0.5 or 1.0 mg/L NAA. Seven known taxoids and four abietanes were obtained from the callus culture incubated under light irradiation on the medium with 1.0 mg/L NAA. Eight taxoids and five abietanes were also separated from the callus culture on the medium with 10 mmol/L beta-cyclodextrin and 1.0 mg/L NAA. The new compounds were identified by analyses of the spectroscopic data and were found to be abieta-6,8,11,13-tetraene-3beta,12-diol (1), 3beta,20-epoxy-12-methoxy-abieta-8,11,13-triene-3alpha,11-diol (2), 3alpha-hydroxy-9(10-->20)abeo-abieta-1,5,8,10(20),13-pentaene-7,11,12-trione (3), 2-hydroxy-9(10-->20)abeo-abieta-1,5,8,10(20),13-pentaene-3,7,11,12-tetraone (4), and 3,7-dioxo-9(10-->20)abeo-12-norabieta-1,5,8,10(20),13-pentaene-11,13-lactone (5), respectively. The yield of paclitaxel and its analogues was markedly decreased in the calluses mentioned above compared with that of standard callus. Instead, abietanes and some taxoids related to biosynthesis of paclitaxel were produced. Taxusin (6) exhibited stronger MDR-reversing activity than verapamil toward 2780 AD tumor cells.     

Taxanes from rooted cuttings of Taxus canadensis

A 3,11-cyclotaxane (1), a new epoxytaxane (2), an abeo-taxane (3), and 26 known taxanes were isolated in rooted cuttings of the Canadian yew (Taxus canadensis) for the first time. Their chemical structures were characterized as 1 beta,2 alpha,9 alpha-trihydroxy-10 beta-acetoxy-5 alpha-cinnamoyloxy-3,11-cyclotaxa-4(20)-en-13-one (1), 2 alpha,9 alpha,10 beta-triacetoxy-11,12-epoxy-20-hydroxytaxa-4-en-13-one (2), and 7 beta,9 alpha,10 beta,13 alpha-tetraacetoxy-11(15-->1)abeo-taxa-4(20),11-diene-5 alpha,15-diol (3). Metabolite 2 is a new taxane, metabolite 1 has been reported previously in the needles of Taxus baccata, and metabolite 3 was previously discovered as a biotransformation product but is now reported as a natural product for the first time.     

Microbial transformation of 20(S)-protopanaxatriol-type saponins by Absidia coerulea

Three 20(S)-protopanaxatriol-type saponins, ginsenoside-Rg1 (1), notoginsenoside-R1 (2), and ginsenoside-Re (3), were transformed by the fungus Absidia coerulea (AS 3.3389). Compound 1 was converted into five metabolites, ginsenoside-Rh4 (4), 3beta,2beta,25-trihydroxydammar-(E)-20(22)-ene-6-O-beta-D-glucopyranoside (5), 20(S)-ginsenoside-Rh1 (6), 20(R)-ginsenoside-Rh1 (7), and a mixture of 25-hydroxy-20(S)-ginsenoside-Rh1 and its C-20(R) epimer (8). Compound 2 was converted into 10 metabolites, 20(S)-notoginsenoside-R2 (9), 20(R)-notoginsenoside-R2 (10), 3beta,12beta,25-trihydroxydammar-(E)-20(22)-ene-6-O-beta-D-xylopyranosyl-(1-->2)-beta-D-glucopyranoside (11), 3beta,12beta-dihydroxydammar-(E)-20(22),24-diene-6-O-beta-D-xylopyranosyl-(1-->2)-beta-D-glucopyranoside (12), 3beta,12beta,20,25-tetrahydroxydammaran-6-O-beta-D-xylopyranosyl-(1-->2)-beta-D-glucopyranoside (13), and compounds 4-8. Compound 3 was metabolized to 20(S)-ginsenoside-Rg2 (14), 20(R)-ginsenoside-Rg2 (15), 3beta,12beta,25-trihydroxydammar-(E)-20(22)-ene-6-O-alpha-L-rhamnopyranosyl-(1-->2)-beta-D-glucopyranoside (16), 3beta,12beta-dihydroxydammar-(E)-20(22),24-diene-6-O-alpha-L-rhamnopyranosyl-(1-->2)-beta-D-glucopyranoside (17), 3beta,12beta,20,25-tetrahydroxydammaran-6-O-alpha-L-rhamnopyranosyl-(1-->2)-beta-D-glucopyranoside (18), and compounds 4-8. The structures of five new metabolites, 10-13 and 16, were established by spectroscopic methods.     

A yew in Israel, new taxane derivatives

Five new taxanes, 5alpha,9alpha,10beta,13alpha-tetraacetoxy-14beta-O-(beta-d-glucopyranosyl)taxa-4(20),11-diene (1), 1beta,2alpha,9alpha,10beta-tetrahydroxy-5alpha-cinnamoyoxytaxa-4(20),11-dien-13-one (2), 2alpha,9alpha,10beta-trihydroxy-5alpha-cinnamoyoxytaxa-4(20),11-dien-13-one (3), 9alpha-acetoxy-2alpha,10beta-dihydroxy-5alpha-cinnamoyoxytaxa-4(20),11-dien-13-one (4), and 2alpha,10beta-diacetoxy-1beta,9alpha-dihydroxy-5alpha-cinnamoyoxy-3,11-cyclotaxa-4(20)-dien-13-one (5), have been identified in a Taxus baccata yew grown in Israel from seeds imported from the United States. We have also characterized 40 previously known taxanes from this plant material. The structures of the new taxanes (1-5) were rigorously established with 1D and 2D NMR data and confirmed by high-resolution FAB-mass spectrometry.     

Dantaxusins A and B, two new taxoids from Taxus yunnanensis

Two new taxane diterpenes, dantaxusin A [5 alpha-cinnamoyloxy-2 alpha,7 beta,13 alpha-triacetoxy-2(3-->20)abeo-taxa-4(20),11-diene-9,10-dione (1)] and dantaxusin B [5 alpha-cinnamoyloxy-9 alpha-hydroxy-10 beta,13 alpha-diacetoxytaxa-4(20),11-diene (2)], were isolated from an ethanol extract of the aerial parts of Taxus yunnanensis along with taxuspine B, 2-deacetoxytaxinine J, taxuyunnanine C, taxinine B, taxuspine C, and taxinine NN-4. The structures of 1 and 2 were established on the basis of 1D and 2D NMR and HRMS spectroscopic methods.     

Four new dammarane saponins from Zizyphus lotus

Five dammarane-type saponins were isolated by means of centrifugal partition chromatography from the leaves of Zizyphus lotus. Their structures were elucidated using a combination of 1D and 2D 1H and 13C NMR spectra and mass spectroscopy. One of these glycosides is the known jujuboside B (5). Three are new jujubogenin glycosides, identified as 3-O-alpha-L-rhamnopyranosyl-(1-->6)-beta-D-glucopyranosyljujubogenin-20-O-(2,3,4-O-triacetyl)-alpha-L-rhamnopyranoside (1), 3-O-alpha-L-rhamnopyranosyl-(1-->6)-beta-D-glucopyranosyljujubogenin-20-O-alpha-L-rhamnopyranoside (2), and 3-O-alpha-L-rhamnopyranosyl-(1-->2)-[(4-sulfo)-beta-D-glucopyranosyl-(1-->3)]-alpha-L-arabinopyranosyljujubogenin (3). The last is a new sulfated derivative of jujubasaponine IV, identified as 3-O-alpha-L-rhamnopyranosyl-(1-->2)-[(4-sulfo)-beta-D-glucopyranosyl-(1-->3)]-beta-D-galactopyranosyl-(20R,22R)-16beta,22:16alpha,30-diepoxydammar-24-ene-3beta,20-diol (4).     

东北红豆杉心材化学成分的研究

目的:研究东北红豆杉心材的化学成分。方法:采用硅胶柱色谱、制备薄层色谱和制备型高效液相色谱等手段对化学成分进行分离和纯化,用现代核磁技术对化合物进行结构鉴定。结果:从东北红豆杉心材分离得到10个化合物,分别鉴定为taxin ine(1),taxusin(2),-βsitosterol(3),1-βhydroxybaccatin I(4),2,α5,α10β-triace-toxy-14β-(2-′m ethyl)butanoyloxy-4(20),11-taxad iene(5),2,α5,α10-βtriacetoxy-14-β(2-′m ethyl-3-′hydroxy-butanoy-loxy)-4(20),11-taxad iene(yunnanxane)(6),9,α10,β13α-triacetoxy-5-αc innamoyltaxa-4(20),11-d iene(7),2-deace-toxytaxin ine J(8),taxezop id ine G(9),2,α7,β9,α10,β13-αpentaacetoxyl-taxa-4(20),11-d ien-5-ol(5-dec innamoyltaxi-n ine J)(10)。结论:化合物4,6,10是首次从该植物中分离得到。     

Secondary metabolites from the roots of Astragalus zahlbruckneri

Four new phenolic glycosides, beta-apiofuranosyl-(1-->2)-beta-glucopyranosides (1-4), along with the cycloartane triterpenes 20(R),25-epoxy-3beta,6alpha,16beta,24alpha-tetrahydroxycycloartane (5) and 20(R),24(S)-epoxy-3beta,6alpha,25-trihydroxycycloartan-16-one (6) were isolated from roots of Astragalus zahlbruckneri. The structure elucidation of all compounds was based on their (1)H and (13)C NMR spectral data including 1D-TOCSY, DQF-COSY, HSQC, and HMBC experiments.     

Saponins of Allium elburzense

A phytochemical investigation of the bulbs of Allium elburzense has been undertaken, leading to the isolation of 13 furostanol and spirostanol saponins, eight of which are new, namely, elburzensosides A1/A2 (1a/1b), B1/B2 (2a/2b), C1/C2 (3a/3b), and D1/D2 (4a/4b). On the basis of spectroscopic analysis, mainly 2D NMR and mass spectrometry, and chemical methods, the structures of the new compounds were determined as furost-2alpha,3beta,5alpha,6beta,22alpha-pentol 3-O-beta-D-glucopyranosyl 26-O-beta-D-glucopyranoside (1a), furost-2alpha,3beta,5alpha,6beta,22alpha-pentol 3-O-[beta-D-glucopyranosyl-(1-->4)-O-beta-D-glucopyranosyl] 26-O-beta-D-glucopyranoside (2a), furost-2alpha,3beta,5alpha,22alpha-tetrol 3-O-beta-D-glucopyranosyl 26-O-beta-D-glucopyranoside (3a), and furost-2alpha,3beta,5alpha,22alpha-tetrol 3-O-[beta-D-xylopyranosyl-(1-->3)-O-beta-D-glucopyranosyl-(1-->4)-O-beta-D-galactopyranosyl] 26-O-beta-D-glucopyranoside (4a), and the corresponding epimers at position 22 (1b-4b). Along with these compounds we have isolated the corresponding 22-O-methyl derivatives that we consider extraction artifacts. All the new elburzensosides A1/A2-D1/D2 possess as a common structural feature an OH-5alphathat is rare among furostanol saponins. The reported compounds have been isolated in large amounts, and this makes A. elburzense a prolific producer of saponins of the furostanol and spirostanol types.     

Chemical constituents of the aerial parts of Schnabelia tetradonta

A phytochemical study on the ethanol extract of the aerial parts of Schnabelia tetradonta led to the isolation of five new compounds, 1-5, together with seven known compounds. The structures of the new compounds were elucidated on the basis of spectral data interpretation as 2alpha,3alpha,23,29-tetrahydroxyolean-12-en-28-oic acid (1), 3-O-beta-d-glucuronopyranosyl-2beta,3beta,16beta-trihydroxy-28-norolean-12-en-15-on-23-oic acid (2), 21-O-beta-d-glucopyranosyl-3beta,21alpha,30-trihydroxyolean-13(18)-en-24-oic acid (3), 6-C-beta-l-arabinopyranosyl-8-C-alpha-l-arabinopyranosylapigenin (4), and 4-acetylaminoethylphenyl 1-O-[6-O-(Z)-p-methoxycinnamoyl-beta-d-glucopyranosyl(1-->2)]-[beta-d-glucopyranosyl(1-->3)]-alpha-l-rhamnopyranoside (5), respectively.     

Cytotoxic furostanol saponins and a megastigmane glucoside from tribulus parvispinus

Two new furostanol saponins, (25R)-26-O-beta-D-glucopyranosyl-5alpha-furostan-2alpha,3beta,22alpha,26-tetraol 3-O-{beta-D-galactopyranosyl-(1-->2)-O-[beta-D-xylopyranosyl-(1-->3)]-O-beta-D-glucopyranosyl-(1-->4)-beta-D-galactopyranoside} (1) and (25R)-26-O-beta-D-glucopyranosyl-5alpha-furostan-3beta,22alpha,26-triol 3-O-{beta-D-galactopyranosyl-(1-->2)-O-[beta-D-xylopyranosyl-(1-->3)]-O-beta-D-glucopyranosyl-(1-->4)-beta-D-galactopyranoside} (2), and their O-methyl derivatives (3 and 4), and a new megastigmane glucoside, (6S,7E,9xi)-6,9,10-trihydroxy-4,7-megastigmadien-3-one 10-O-beta-D-glucopyranoside (6), along with one known spirostanol saponin, gitonin (5), and four known megastigmane glucosides were isolated from the aerial parts of Tribulus parvispinus. Their structures were established by detailed spectroscopic analysis. The cytotoxic activities of 1-6 against U937, MCF7, and HepG2 cells were evaluated. Compounds 2 (IC(50) 0.5 microM) and 5 (IC(50) 0.1 microM) showed the highest activity against U937 cells.     

素馨花三萜皂苷类化学成分研究

目的:研究木犀科茉莉属植物素馨花干燥花蕾的化学成分。方法:通过硅胶柱色谱、Sephadex LH-20柱色谱和重结晶等方法进行分离纯化,根据化合物的理化性质和波谱数据鉴定结构。结果:从素馨花干燥花蕾70%乙醇提取物中分离得到6个三萜皂苷类化合物,分别鉴定为3-O-α-L-吡喃鼠李糖基(1→2)-β-D-吡喃木糖基常春藤皂苷元-28-O-β-D-吡喃半乳糖基(1→6)-β-D-吡喃半乳糖酯苷(1)、常春藤皂苷元3-O-β-D-吡喃葡萄糖基(1→3)-α-L-吡喃阿拉伯糖苷(2)、2α,3β,23-trihydroxyolean-12-en-28-oic-O-β-D-glucopyranosyl ester(3)、常春藤皂昔元-3-O-β-D-吡喃木糖基(1→3)-α-L-吡喃鼠李糖基(1→2)-α-L-吡喃阿拉伯糖苷(4)、2α,3β,23-trihydroxyolean-12-en-28-oic-O-α-L-rhamnopyranosyl(1→4)-O-β-D-glucopyranosyl(1→6)-β-D-glucopyranosyl ester(5)、常春藤皂苷元-3-O-α-L-吡喃鼠李糖基(1→)2-α-L-吡喃阿拉伯糖苷(6)。结论:化合物1为新化合物,化合物26为首次从茉莉属植物中分离得到。     

Trypanocidal withanolides and withanolide glycosides from Dunalia brachyacantha.

Two new withanolide glycosides, (20R,22R)-O-(3)-alpha-L-rhamnopyranosyl(1-->4)-beta-D-glucopyranosyl-1 alpha,12 beta-diacetoxy-20-hydroxywitha-5,24-dienolide (3) and (20R,22R)-O-(3)-beta-D-xylopyranosyl(1-->3)-[beta-D-xylopyranosyl(1-->4)]-beta-D-glucopyranosyl-1 alpha-acetoxy-12 beta,20-dihydroxywitha-5,24-dienolide (4), were isolated from the leaves and root of Dunalia brachyacantha. Their aglycones, (20R,22R)-1 alpha,12 beta-diacetoxy-3 beta,20-dihydroxywitha-5,24-dienolide (or 1 alpha,12 beta-diacetyldunawithagenine) and (20R,22R)-1 alpha-acetoxy-3 beta,12 beta,20-trihydroxywitha-5,24-dienolide (or 1 alpha-acetyl-12 beta-hydroxydunawithagenine), are novel. The known 18-acetoxywithanolide D (1) and 18-acetoxy-5,6-deoxy-5-withenolide D (2) were also isolated from the leaves. These last two compounds were shown to be responsible for the trypanocidal, leishmanicidal, and bactericidal activities manifested by the crude ethanolic extract. The structures were deduced from spectroscopic data and on the basis of chemical evidence.     

Microbial transformation of cephalomannine by Luteibacter sp

Luteibacter sp., a new bacterium isolated from the soil around a Taxus cuspidata Sieb. et Zucc plant, was studied for its capability to metabolize cephalomannine (1). After preparative fermentation, eight metabolites were obtained and characterized as baccatin III (2), baccatin V (3), 10-deacetylbaccatin III (4), 10-deacetyl-10-oxobaccatin V (5), 7-epicephalomannine (6), 10-deacetylcephalomannine (7), 10-deacetyl-7-epicephalomannine (8), and 3'-N-debenzoyl-3'-N-(2-methylbutyryl)-7-epitaxol (9). Among these metabolites, 9 is a new compound. Epimerization of the 7beta-OH group and hydrolysis of the C-13 side-chain were the two major reactions in this bioprocess. However, the biotransformation of 7beta-D-xylosyl-10-deacetyltaxol (10) with the same strain yielded a C-13 side-chain eliminated product without epimerization at C-7 (11). Metabolites 5-9 and 11, together with 1 and paclitaxel, were evaluated for their inhibitory activities against five human cancer cell lines (HCT-8, Bel-7402, BGC-823, A549, and A2780). All these compounds showed less potent activities than paclitaxel, which is currently used in clinical chemotherapy.     

New triterpenoid saponins from Maesa japonica

New triterpenoid saponins, maejaposides A, B, C, D, and E, were isolated from the roots of Maesa japonica and were, respectively, defined to be 3-O-[beta-D-xylopyranosyl-(1-->2)-alpha-L-rhamnopyranosyl-(1-->2)-bet a-D-galactopyranosyl-(1-->3)] [beta-D-galactopyranosyl-(1-->2)]beta-D-glucuronopyranosides of 22alpha-[(Z)-2-hexenoyloxy]-13beta,28-oxido-olean++ +-16alpha, 28alpha-diol (1); 22alpha-[2'-methylbutanoyl]-13beta, 28-oxido-olean-16alpha,28alpha-diol (2a) and 22alpha-angeloyloxy-13beta,28-oxido-olean-16a lpha,28alpha-diol (2b); 21beta,22alpha-diangeloyloxy-13beta,28-oxido- olean-16alpha, 28alpha-diol (3); 21beta-angeloyloxy, 22alpha-(2'-methylbutanoyl)-13beta,28-oxido-olean++ +-16alpha, 28alpha-diol (4), and 21beta-angeloyloxy, 22alpha-[(Z)-2'-hexenoyl]-13beta,28-oxido-olean- 16alpha,28alpha-diol (5). Their structures were established on the basis of extensive NMR (DEPT, COSY, HOHAHA, HETCOR, HMBC, and NOESY) and ESIMS/MS studies, along with chemical degradation.     

Hemolytic steroid disulfates from the far eastern starfish Pteraster pulvillus

Six steroidal ophiuroid-type disulfates, namely, disodium salts of (20R)-cholest-5-ene-3alpha,4beta,21-triol 3, 21-disulfate (1), (20R)-5alpha-cholestane-3alpha,4beta,21-triol 3,21-disulfate (2), (20R)-5alpha-cholestane-2beta,3alpha,21-triol 3,21-disulfate (3), and (20R)-5alpha-cholestane-3alpha,21-diol 3,21-disulfate (4), the dityrammonium salt of (20R)-5alpha-cholestane-3alpha,21-diol 3,21-disulfate (5), and a mixture of sodium and tyrammonium salts (1:1) of (20R)-cholest-5-ene-3alpha,21-diol 3,21-disulfate (6), have been isolated from the ethanolic extracts of Far Eastern starfish Pteraster pulvillus. Steroids 2 and 3 are new compounds. Steroids 1, 2, and 4-6 showed hemolytic activity to mouse erythrocytes with HC(50) values of 8.0 x 10(-5), 4.5 x 10(-5), 1.0 x 10(-5), 1.8 x 10(-5), and 3.3 x 10(-5) M, respectively.     

Isolation and structures of guaianolides from Carpesium macrocephalum

Two new guaianolides, 4alpha,10alpha-dihydroxy-1beta(H),5beta(H)-guai-11(13)-en-8alpha,12-olide (2) and 4beta,10beta-dihydroxy-5alpha(H)-1,11(13)-guaidien-8alpha,12-olide (3), from Carpesium macrocephalum were isolated, and their structures were elucidated on the basis of spectroscopic studies.     

Iridoids from Crescentia alata

Four new 11-nor-iridoids, 6beta,7beta,8alpha,10-tetrahydroxy-cis-2-oxabicyclo[4.3.0]nonan-3-one (1), 6beta,7beta,8alpha,10-tetra-p-hydroxybenzoyl-cis-2-oxabicyclo[4.3.0]nonan-3-one (2), 1beta,6beta,7alpha,8alpha,10-pentahydroxy-cis-2-oxabicyclo[4.3.0]nonane (3), and 6beta-hydroxy-2-oxabicyclo[4.3.0]Delta8-9-nonen-1-one (4), were isolated from the pulp of the fruits of Crescentia alata. Although a limited number of Crescentia species have been studied chemically, iridoids lacking C-11 have been isolated from the fruits of these species, and the isolation of compounds 1-4 from C. alata is in accordance with the constituents of the species previously analyzed. The structures of these compounds were established on the basis of IR, UV, 1H and 13C NMR, DEPT, COSY, HSQC, HMBC, MS, and X-ray data.