A new sesquiterpene ester inhibiting no production from the fruits of Celastrus orbiculatus

A new β-dihydroagarofuran sesquiterpene ester, 1β,2β,6α, 13-tetraacetoxy-9α-cinnamoyloxy-β-dihydroagarofuran (1), and the known compound 1β,6α,13-triacetoxy-9α-benzoyloxy-β-dihydroagarofuran (2), have been isolated from the fruits of Celastrus orbiculatus Thunb. Their structures have been elucidated on the basis of spectroscopic methods. Compound 1 shows moderate activity of inhibiting LPS-induced nitric oxide production in murine macrophage RAW264.7 cells, with an IC₅₀ of 55.4 μM.     

New eudesmane-type sesquiterpenoids from the root bark of Pseudolarix kaempferi

Abstract

The phytochemical investigation of the root bark of Pseudolarix kaempferi yielded eight eudesmane-type sesquiterpenoids, including three new ones, 1α-hydroxyl-4(14)-en-β-dihydroagarafuran (1), 1α, 2α-diacetoxy-8β-isobutanoyloxy-9α-benzoyl oxy-15-β-(β-furancarbonyloxy)-4β, 6β-dihydroxy-β-dihydroagarofuran (7), and 1α-acetoxy-2 α-furancarbonyloxy-8β-isobutanoyloxy-9α-benzoyloxy-15β-(β-acetoxy)-4β, 6β-dihydroxy-β-dihydroagarofuran (8). Herein the new compounds 7 and 8 were reported as a mixture. The molecular structures of the isolated compounds were elucidated on the basis of extensive spectroscopic analysis, including UV, IR, NMR, and MS, and comparison with the literature data.     

Two new sesquiterpene polyol esters from the root barks of Celastrus angulatus

Angulatin F (1) and angulatin I (2), two new sesquiterpene polyol esters, were isolated from the root barks of Celastrus angulatus, together with six known compounds 1β,2β-diacetoxy-4α,6α-dihydroxy-8α-isobutanoyloxy-9β-benzoyloxy-15-(α-methyl) butanoyloxy-β-dihydroagrofuran (3), angulatin A (4), angulatin B (5), celangulatin E (6), 1β,2β,15-triacetoxy-4α,6α-dihydroxy-8α-isobutanoyloxy-9β-benzoyloxy-β-dihydroagrofuran (7), and celangulin I (8). The structures of 1 and 2 were elucidated as 1β,2β,6α,15-tetraacetoxy-4α-hydroxy-8β,9α-difuroyloxy-β-dihydroagrofuran and 1β,2β,6α,8β,15-pentaacetoxy-4α-hydroxy-9β-furoyloxy-β-dihydroagrofuran by spectroscopic means.     

Two new diterpenoids from coleus forskohlii

Two new diterpenoids, forskolins I and J, have been isolated in our further investigation on Coleus forskohlii (Willd.) Briq. collected in Yunnan Province. Their structures have been determined as 1α,6β-diacetoxy-7β,9α-dihydroxy-8,13-epoxylabd-14-en-11-one (1) and 1α,9α-dihydroxy-6β,7β-diacetoxy-8,13-epoxylabd-14-en-11-one (2) by spectral methods (including 1D and 2D NMR techniques).     

Two new sesquiterpene polyol esters from the root barks of Celastrus angulatus

Angulatin F (1) and angulatin I (2), two new sesquiterpene polyol esters, were isolated from the root barks of Celastrus angulatus, together with six known compounds 1β,2β-diacetoxy-4α,6α-dihydroxy-8α-isobutanoyloxy-9β-benzoyloxy-15-(α-methyl) butanoyloxy-β-dihydroagrofuran (3), angulatin A (4), angulatin B (5), celangulatin E (6), 1β,2β,15-triacetoxy-4α,6α-dihydroxy-8α-isobutanoyloxy-9β-benzoyloxy-β-dihydroagrofuran (7), and celangulin I (8). The structures of 1 and 2 were elucidated as 1β,2β,6α,15-tetraacetoxy-4α-hydroxy-8β,9α-difuroyloxy-β-dihydroagrofuran and 1β,2β,6α,8β,15-pentaacetoxy-4α-hydroxy-9β-furoyloxy-β-dihydroagrofuran by spectroscopic means.     

Chemical constituents of Isodon nervosus and their cytotoxicity

Two new ent-kaurane diterpenoids, 6,20,15α-trihydroxy-6,7-seco-1α,7-olide-ent-kaur-16-ene (1) and 7β,12α-dihydroxy-6β,15β-diacetoxy-7α,20-epoxy-ent-kaur-2,16-dien-1-one (2), together with the six known compounds, were isolated from the aerial part of Isodon nervosus. The structures of the new compounds were determined by spectral methods (1D, 2D NMR, and MS). Six compounds were assayed for their cytotoxicity against HL60, SMMC-7721, and HeLa human cell lines. Compounds 5, 7, and 8 showed significant cytotoxicity.     

A new dihydroagarofuranoid sesquiterpene from the roots of Tripterygium hypoglaucum

A new sesquiterpene ester (1) has been isolated from the root bark of Tripterygium hypoglaucum. The structure was determined as 1α-acetoxy-6β,9β-dibenzoyloxy-4β-hydroxy-dihydroagarofuran by the extensive analysis of NMR data, and the absolute configurations were established as 1R, 4R, 6S, and 9R by application of the CD excitation chirality method. Compound 1 exhibited weak cytotoxicity against HeLa cells, with an IC₅₀ value of 30.2 μM.     

Three new diterpenoids from Coleus forskohlii Briq

Three new diterpenoids, forskolin G(2), forskolin H(3), forskolin I(4), were isolated from the whole plant of the Coleus forskohlii Briq., and their structures were elucidated as 1α,6β-diacetoxy-8,13-epoxylabd-14-en-11-one, 1α-hydroxy-6β,7β-diacetoxy-8,13-epoxylabd-14-en-11-one, and 1α,9α-dihydroxy-6β,7α-diacetoxy-8,13-epoxylabd-14-en-11-one on the basis of spectral data.     

Two novel sesquiterpenoids from Ainsliaea fragrans Champ.

A new sesquiterpene lactone, 3β-O-β-d-glucopyranosyl-8α-hydroxy-11α,13-dihydrozaluzanin C (1), and a novel trinorguaiane-type sesquiterpene, 4β,10α-dimethyl-1β,5α-bicycle[3,5,0]dec-6-en-4α,10β-diol (2), together with three known compounds, glucozaluzanin C (3), 11α,13-dihydrozaluzanin C (4), and 8α-hydroxy-11α,13-dihydrozaluzanin C (5), were isolated from the whole plant of Ainsliaea fragrans Champ. The structures of 1 and 2 were elucidated on the basis of detailed spectral analysis. Structures of the known compounds were identified by comparison of its spectral data with those values in the literature.     

Biotransformation of α- and 6β-santonin by fungus and plant cell cultures

One fungus, Abisidia coerulea IFO 4011, and suspended cell cultures of one plant, Asparagus officinalis, were employed to bioconvert α- and 6β-santonin. Incubation of α-santonin with the cell cultures of the fungus afforded two products, 11β-hydroxy-α-santonin (1, in 76.5% yield) and 8α-hydroxy-α-santonin (2, in 2.0% yield). And from 6β-santonin, four major products (3, 4, 5 and 6) and four minor products (7, 8, 9 and 10) were obtained, including 8α-hydroxylated products in trace yields. Very interestingly, a skeletal rearrangement occurred and a guaiane product (13) formed in a very low yield when α-santonin incubating with A. officinalis cell cultures, while not in the case of 6β-santonin as substrate. Among the obtained 15 products, 2, 7, 8, 9, 10 and 12 are new compounds. The fact of 8α hydroxylation of santonin enables the formation of 8,12-eudesmanolide instead of 6,12-eudesmanolide and some useful modification at C-8 position. In addition, these reactions would provide evidence for the biogenesis between different types of eudesmane and/or guaiane compounds in the plants in nature.     

Three New Taxane Diterpenoids from the Seeds of the Chinese Yew,Taxus Chinensis var Mairei

Abstract

Three new taxoids were isolated from the seeds of the Chinese yew, Taxus chinensis var mairei, their structures were established as 9α,13α-diacetoxy-5α-cinnamoyloxy-11(15 → 1)-abeo-taxa-4(20), 11-diene-10β,15-diol, 2α,9α,10β-triacetoxy-taxa-4(20),11-diene-5α,13α-diol and 2α,7β,10β-triacetoxy-5α-cinnamyloxy-9α-hydroxy-taxa-4(20),11-diene-13-one on the basis of 1D, 2D NMR, and MS spectral analyses.     

Two new triterpenoids from the resin of Styrax tonkinensis

Two new triterpenoids, 3β,6β-dihydroxy-12-oxo-13Hα-olean-28,19β-olide (1) and 3-oxo-olean-11,13(18)-dien-28,19β-olide (2) were isolated from the resin of Styrax tonkinensis (Pier.) Craib. The structures of both triterpenoids were determined by physicochemical and spectroscopic methods. Compound 1 is the second triterpene found with cis-fused C/D ring from the resin, which is rarely observed in oleanane-type triterpenes.     

Three new cassane diterpenes from the seeds of Caesalpinia minax Hance

Three new cassane-diterpene-lactones, methyl 1α,7β-diacetoxy-5α,12α-dihydroxy-cass-13(15)-en-16,12-olide-17β-carboxylate (1), methyl 7β-acetoxy-1α,5α,12α-trihydroxy-cass-13(15)-en-16,12-olide-17β-carboxylate (2), and 12α-ethoxyl-1α,6α,7β-triacetoxy-5α,14β-dihydroxy-cass-13(15)-en-16,12-olide (3), were isolated from the seeds of Caesalpinia minax Hance. Their structures were established on the basis of HR-ESI-MS, 1D and 2D NMR spectral analysis.     

Four new minor taxanes from cell cultures of Taxus chinensis

Four new minor taxanes (1–4) have been isolated from Ts-19 cell cultures of Taxus chinensis together with five known taxanes (5–9) by silica gel chromatography combined with semi-preparative HPLC chromatography. On the basis of the analyses of the chemical and spectroscopic (IR, MS, 1D, and 2D NMR) data, the structures of new compounds were elucidated as 5α-hydroxy-2α,10β-diacetoxy-14β-(3-hydroxy-2-methyl-butyryl)oxytaxa-4(20),11-diene (1), 2α,5α,10β-triacetoxy-14β-(2-hydroxy-propionyl)oxytaxa-4(20),11-diene (2), 2α,5α,10β-triacetoxy-14β-(2-hydroxy-3-methyl-butyryl)oxytaxa-4(20),11-diene (3), and 2α-benzoxy-4α,9α,10β,13α-tetraacetoxytax-11-ene (4), respectively. Compounds 1–5 were pharmacologically evaluated for their cytotoxicities against five human cancer cell lines (HCT-8, Bel-7402, BGC-823, A549, and A2780) and their reversing activity towards multi-drug resistance A549/taxol tumor cell line, and the results showed that all of the tested compounds exhibited very low cytotoxicities, while compound 4 possessed twice the reversing activity as that of verapamil at 10 μM.     

Triterpene saponins of Maesa lanceolata stem wood

Phytochemical analysis of aqueous MeOH extract of Maesa lanceolata stem wood has led to the isolation of four new triterpene saponins characterized as 16α,21β-diacetoxy-22α-angeloyl-28-hydroxyolean-12-ene 3-O-[α-rhamnopyranosyl-(1″″ → 6?)-β-glucopyranosyl-(1? → 3′)][β-glucopyranosyl-(1″ → 2′)]-β-glucuronopyranoside (1), 16α-acetoxy-21β-hydroxy-22α-angeloyl-13β,28-oxydoolean-28α-ol 3-O-[α-rhamnopyranosyl-(1″″ → 6?)-β-glucopyranosyl-(1? → 4′)][β-glucopyranosyl-(1″ → 2′)]-α-arabinopyranoside (2), 16α-acetoxy-21β,22α-diangeloyl-13β,28-epoxyoleanane 3-O-[α-rhamnopyranosyl-(1″″ → 6?)-β-glucopyranosyl-(1? → 4′)][β-glucopyranosyl-(1″ → 2′)]-β-xylopyranoside (3), and 16α,22α-diacetoxy-13β,28-oxydoolean-28α-ol 3-O-[β-glucopyranosyl-(1″ → 2′)][β-glucopyranosyl-(1? → 3′)]-β-glucuronopyranoside (4), together with the known compounds β-acetylamyrin, physcion, emodin, chrysophanol, ursolic acid, 16α-hydroxy-12-oleanene 3-O-glucoside, β-amyrin, sitosterol 3-O-β-glucoside, stigmasterol, and 3β,28-dihydroxyolean-12-ene. Their structural elucidation was accomplished by homo- and heteronuclear 2D NMR technique as well as comparison with data from known compounds. The in vitro antibacterial activity of the aqueous MeOH extract was also investigated and zones of inhibition ranging from 32 ± 1.1 to 14 ± 0.2 mm were observed. Among the isolates, compound 1 was the most active with an minimum inhibitory concentration value of 25 μg/ml against Staphylococcus aureus.     

A new isopimarane-type diterpene and a new natural atisane-type diterpene from Excoecaria agallocha

From the woods of Excoecaria agallocha, a new isopimarane-type diterpene, 3α,11β-dihydroxy-ent-isopimara-8(14),15-dien-2-one (1) and a new natural atisane-type diterpene, 16β-hydroxy-ent-atisan-3-one (2) were isolated together with three known compounds, ribenone (3), ent-labda-8(17),13E-diene-3β,15-diol (4), and ent-3β-hydroxybeyer-15-ene-2,12-dione (5). Their structures were determined by spectral data and x-ray crystallography evidence.     

7α-和7β-甲基-10β,17β-二乙酰氧基-△4-雌甾烯-3酮的抗早孕作用

7α-和7β-甲基-10β,17β-二乙酰氧基-△⁴-雌甾烯-3酮(简称7α-和7β-甲-乙氧雌酮)对小鼠抗早孕ED₅₀分别为1.6和5.5 mg/kg。7α-甲-乙氧雌酮在大鼠也有抗早孕作用并使血浆孕酮浓度降低,应用10 μg/ml浓度能抑制离体妊娠大鼠卵巢孕酮合成。7α-和7β-甲-乙氧雌酮与兔子宫胞浆雌二醇受体的相对结合亲和力(RBA)分别为10.8和1.5,与孕酮受体的RBA均<1.7α-和7β-甲-乙氧雌酮都有较弱的雌激素和抗雌激素活性。     

Diterpenoids from the freshwater green algae Rhizoclonium hieroglyphicum with antibacterial activity

Three new isopimarane diterpenes 7β-hydroxy-19α-methylmalonyloxy-isopimara-8(14),15-diene (1), 7β-hydroxy-14-oxo-isopimara-8(9),15-dien-19oic acid (2), and 7β-hydroxy-14-oxo-19α-methylmalonyloxy-isopimara-9(11),15-diene (3) in addition to the known compounds isopimaric acid (4), 7oxo-13-epi-pimara-14,15-dien-18oic acid (5), 7oxo-13-epi-pimara-8,15-dien-18oic acid (6), and 6β-hydroxyisopimaric acid (7) were isolated from the hexane extract of Rhizoclonium hieroglyphicum. The structures of compounds 1–7 were established by 1D and 2D NMR techniques. The isolated diterpenoids were screened for antimicrobial activity against gram-positive and gram-negative bacteria and yeast strains.     

Feruhermonins A–C: three daucane esters from the seeds of Ferula hermonis (Apiaceae)

Seventeen daucane esters have been isolated from the seeds of Ferula hermonis Boiss (Apiaceae). Three of these sesquiterpenes, 4β-hydroxy-6α-benzoyl-7-daucen-9-one (1), 4β, 8β-dihydroxy-6α-benzoyl-dauc-9-ene (2), and 4β, 9α-dihydroxy-6α-benzoyl-dauc-7-ene (4), named feruhermonins A–C, respectively, are novel natural products. The structures of these compounds were elucidated unequivocally by a series of 1D and 2D NMR analyses. Although 4β, 8β-dihydroxy-6α-(4-hydroxy-3-methoxybenzoyl)-dauc-9-ene (3) was reported previously, the complete spectroscopic data for this compound are presented here for the first time.     

Two new triterpenoids from the resin of Boswellia carterii

Two new triterpenoids, 3-oxotirucalla-7,9(11),24-trien-21-oic acid (1) and 18Hα,3β,20β-ursanediol (2), along with 15 known triterpenes, α-amyrin, α-boswellic acid, β-boswellic acid, acetyl α-boswellic acid, acetyl β-boswellic acid, 9,11-dehydro-β-boswellic acid, 9,11-dehydro-α-boswellic acid, acetyl 11α-methoxy-β-boswellic acid, 11-keto-β-boswellic acid, acetyl 11-keto-β-boswellic acid, acetyl α-elemolic acid, 3β-hydroxytirucalla-8,24-dien-21-oic acid, elemonic acid, 3α-hydroxytirucalla-7,24-dien-21-oic acid, and 3α-hydroxytirucall-24-en-21-oic acid, were isolated from the resin of Boswellia carterii Birdw.