Chlorinated Withanolides from Withania somnifera

A chlorinated withanolide, 6α-chloro-5β,17α-dihydroxywithaferin A (1), and nine known withanolides, 6α-chloro-5β-hydroxywithaferin A (2), (22R)-5β-formyl-6β,27-dihydroxy-1-oxo-4-norwith-24-enolide, withaferin A, 2,3-dihydrowithaferin A, 3-methoxy-2,3-dihydrowithaferin A, 2,3-didehydrosomnifericin, withanone, withanoside IV and withanoside X, were isolated from Withania somnifera (Solanaceae). All structures were elucidated on the basis of spectroscopic methods (IR, HRESIMS, 1D/2D NMR). X-ray crystallography confirmed the absolute configuration of 1.     

Unusual withanolides from aeroponically grown Withania somnifera

In an attempt to maximize production and the structural diversity of plant metabolites, the effect of growing the medicinal plant Withania somnifera under soil-less aeroponic conditions on its ability to produce withaferin A and withanolides was investigated. It resulted in the isolation and characterization of two compounds, 3α-(uracil-1-yl)-2,3-dihydrowithaferin A (1) and 3β-(adenin-9-yl)-2,3-dihydrowithaferin A (2), in addition to 10 known withanolides including 2,3-dihydrowithaferin A-3β-O-sulfate. 3β-O-Butyl-2,3-dihydrowithaferin A (3), presumably an artifact formed from withaferin A during the isolation process was also encountered. Reaction of withaferin A with uracil afforded 1 and its epimer, 3β-(uracil-1-yl)-2,3-dihydrowithaferin A (4). The structures of these compounds were elucidated on the basis of their high resolution mass and NMR spectroscopic data.     

Terpenes and steroids from leaves of Oxandra sessiliflora R. E. Fries

The EtOH extract from the leaves of Oxandra sessiliflora R. E. Fries (Annonaceae) was partitioned using hexane and CH₂Cl₂. After several chromatographic steps, caryophyllene oxide and spathulenol were isolated from hexane phase while, from CH₂Cl₂ phase, we isolated (E)-phytol, spathulenol, 4β,10α-dihydroxyaromadendrane, 1β,6α-dihydroxyeudesm-4(15)-ene, and 4α,7β,10α-trihydroxyguai-5-ene, the latter being a new sesquiterpene derivative. Additionally, a mixture of steroids (campesterol, sitosterol, and stigmasterol) was obtained from the CH₂Cl₂ phase. The isolated compounds were characterized by mass spectrometry and analysis of their ¹H and ¹³C NMR spectroscopic data, including bidimensional analysis.     

Neolignans from an Aniba species

A benzene extract of the trunk wood of an Aniba species contained 3a-allyl-2-aryl-5-methoxy-3-methyl-2,3,3a,6-tetrahydro-6-oxobenzofurans which may be responsible, through sequential Cope, retro-Claisen and Claisen rearrangements respectively for the formation of the co-occurring 5-allyl-2-aryl-5-methoxy-3-methyl-2,3,5,6-tetrahydro-6-oxobenzofurans; the 6-O-allyl-2-aryl-5-methoxy-3-methyl-2,3-dihydrobenzofurans and the 7-allyl-2-aryl-6-hydroxy-5-methoxy-3-methyl-2,3-dihydrobenzofurans. The examination of the stereochemistry of these products led to the formulation of burchellin, previously isolated from Aniba burchellii Kostermans, as (2S,3S,3aR)-3a-allyl-5-methoxy-2-piperonyl-3-methyl-2,3,3a,6-tetrahydro-6-oxobenzofuran. The structure 1-allyl-4,8-dihydroxy-7-(3-methoxy-4,5-methylenedioxyphenyl)-6-methyl-3-oxobicyclo[3,2,1]octane is tentatively proposed for an additional neolignan.     

Sesquiterpenes from severinia buxifolia

Three new sesquiterpenes were isolated from Severinia buxifolia, and identified as α-santalen-11-one, dihydro-α-santalen-12-one, and 12,13-epoxy-α-santalene, respectively. α-Photosantalol A, Δ^13,14-iso-α-santalol, α-santalene and (E)-5-(2,3-dimethyl-3-nortricyclyl)pent-3-en-2-one were also isolated and characterized.     

Furanocoumarins from Dorsteniafoetida

The linear furanocoumarins 5-(2,3-epoxy-3-methyl-butoxy)-chalepensin, 5-methoxy-3-(3-methyl-2,3-dihydroxybutyl)-psoralen-diacetate (7), 5-methoxy-3-[3-(β-d-glucopyranosyloxy)-2-acetyloxy-3-methyl-butyl]-psoralen and 5-(3-methyl-2,3-dihydroxybutyloxy)-3-[3-(β-d-glucopyranosyloxy)-2-hydroxy-3-methyl-butyl]-psoralen, and the coumarin derivative 7-hydroxy-5-methoxy-6-carboxymethyl-3-[3-(β-d-glucopyranosyloxy)-2-hydroxy-3-methyl-butyl]-coumarin were isolated from the leaves of Dorstenia foetida (Moraceae) along with the known compounds psoralen, bergapten, isopimpinellin, phellopterin, 5-methoxychalepensin and turbinatocoumarin. Further furanocoumarins were characterized by ESI-MS/MS investigations. The nonpolar extracts of D. foetida exhibit antifungal, antibacterial and cytotoxic activity, however, no anthelminthic activity.     

Polyhydroxylated steroids from an endophytic fungus, Chaetomium globosum ZY-22 isolated from Ginkgo biloba

A novel polyhydroxylated C₂₉-sterol, 25ξ-methyl-22-homo-5α-cholest-7,22-diene-3β,6β,9α-triol, designated globosterol (1), together with one known tetrahydroxylated ergosterol (22E, 24R)-ergosta-7,22-diene-3β,5α,6β,9α-tetraol (2) has been isolated from the cultures of an endophytic fungus, Chaetomium globosum ZY-22 originated from the plant Ginkgo biloba. The structures and relative configurations of 1 and 2 were established on the basis of extensive spectroscopic analyses including 1D and 2D NMR (¹H-¹H COSY, HSQC, HMBC, and NOESY) experiments and comparison with the literature. Globosterol (1) possesses an unprecedented 25-methyl Δ²²-C₁₀-side chain and Δ⁷-3β,6β,9α-hydroxy-steroid nucleus, which represents the first example for C₂₉-steroids of the group.     

A new epoxidic ganoderic acid and other phytoconstituents from Ganoderma lucidum

A new epoxidic ganoderic acid, 8α,9α-epoxy-3,7,11,15,23-pentaoxo-5α-lanosta-26-oic acid (1), together with the known compounds 3β-hydroxy-7,11,15,23-tetraoxo-5α-lanosta-8-en-26-oic acid (2), ergosta-7,22-diene-3β-yl pentadecanoate (3), ergosta-7,22-diene-3β-ol (4), β-sitosterol (5), fatty acids (6–10), fatty acid ester (11) and octadecane (12) were isolated from the fruiting bodies of Ganoderma lucidum from south India. Their structures were determined by ¹H, ¹³C, ¹³C DEPT, ¹H–¹H COSY, HMBC, HSQC, NOESY NMR, FT-IR, UV–vis and FABMS spectral analysis. Compounds (1–3) exhibited good antifungal activity against Candida albicans in disc diffusion assay (100 μg/disc). Steroid ester (3) showed moderate anti-inflammatory activity (59.7% inhibition, 100 mg/kg body weight) in carrageenan-induced paw edema.     

24α-Methyl-5α-cholest-7-en-3β-ol from seed oil of Helianthus annuus

24-Methyl-5α-cholest-7-en-3β-ol (24-methyllathosterol) isolated from the seed oil of Helianthus annuus was shown to have 24α-configuration by ¹H NMR spectroscopy. The stereochemistry at C-24 of some other 24-alkylsterols isolated from this plant material also was determined.     

Two carabrane-type sesquiterpenes from Vladimiria souliei

Two new carabrane sesquiterpenes, 4,8-dioxo-6β-methoxy-7β,11-epoxy carabrane (1), and its isomer, 4,8-dioxo-6β-methoxy-7α,11-epoxy carabrane (2) were isolated from the roots of Vladimiria souliei. Their structures were elucidated by spectroscopic methods (IR, ESI-MS, HR-ESI-MS, 1D and 2D NMR).     

Two new cyclohexylethanol derivatives from the whole plants of Incarvillea delavayi and their inhibition on LPS-induced NO release in BV-2 cells

Delavatones A (4β, 7α-dihydroxy-7β-(13-methylpent-11-one-12-ene)-octahydrobenzofuran, 1) and B (4β, 7α-dihydroxy-7β-(propan-9-one)-octahydrobenzofuran, 2), two structurally unique cyclohexylethanol derivatives with a substituted alkyl chain, were isolated from the 90% ethanol extract of the whole plants of Incarvillea delavayi. The structures of delavatones A and B were characterized by the interpretation of 1D and 2D NMR spectroscopic data in combination with NMR chemical shift calculation coupled with DP4+ probability analysis. In an in vitro assay for anti-inflammatory effect, delavatones A and B displayed remarkable suppression on NO production in LPS-induced BV-2 cells at concentrations ranging from 6 μM to 100 μM.     

Solanopubamine,a steroidal alkaloid from Solanum pubescens

Aerial parts of Solanum pubescens yielded a new steroidal alkaloid, solanopubamine, the structure of which was elucidated as 3β-amino-5α,22αH,25βH-solanidan-23β-ol by ¹³C NMR, ¹H NMR, IR, mass spectral analysis and chemical degradation methods.     

Solanolide,a steroid lactone sapogenin from Solanum hispidum

Solanolide, a new C₂₂ steroid lactone sapogenin isolated from the leaves of Solanum hispidum Pers., has been characterized as 3β, 6α, 16β-trihydroxy-5α-pregnane-20S-carboxylic acid (22, 16)-lactone from ¹H and ¹³C NMR analyses and correlation with neochlorogenin.     

Oligofuro- and spiro-stanosides of Asparagus adscendens

Two oligofurostanosides and two spirostanosides, isolated from a methanol extract of Asparagus adscendens (leaves), were characterized as 3-O-[{α-l-rhamnopyranosyl (1 → 4)} {α-l-rhamnopyranosyl (1 → 6)}-β-d-glucopyranosyl]-26-O-[β-d-glucopyranosyl]-22α-methoxy-(25S)-furost-5-en-3β,26-diol (Adscendoside A), 3-O-[{α-l-rhamnopyranosyl (1 → 4)} {α-l-rhamnopyranosyl (1 → 6)}-β-d-glucopyranosyl]-26-O-[β-d-glucopyranosyl]-(25S)-furost-5-en-3β,22α,26-triol-(Adscendoside B), 3-O-[{α-l-rhamnopyranosyl (1 → 6)}-β-d-glucopyranosyl]-(25S)-spirostan-5-en-3β-ol (Adscendin A) and 3-O-[{α-l-rhamnopyranosyl (1 → 4)} {α-l-rhamnopyranosyl (1 → 6)}-β-d-glucopyr anosyl]-(25S)-spirostan-5-en-3β-ol (Adscendin B), respectively. Adscendin B and Adscendoside A are the artefacts of Adscendoside B formed through hydrolysis and methanol extraction respectively.bl]     

New sweet diterpene glucosides from Stevia rebaudiana

From the leaves of Stevia rebaudiana, two new sweet glucosides, rebaudiosides A and B, were isolated besides the known glucosides, stevioside and steviolbioside. On the basis of IR, MS, ¹H and ¹³C NMR as well as chemical evidences, the structure of rebaudioside B was assigned as 13-O-[β-glucosyl(1-2)-β-glucosyl(1-3)]-β-glucosyl-steviol and rebaudioside A was formulated as its β-glucosyl ester.     

Steroid sapogenins from Tristagma uniflorum

From bulbs of Tristagma uniflorum the known sapogenins tigogenin, neotigogenin and (20S,22R,25S)-5α-spirostan-3β,25-diol, as well as the new (20S,22R,25R)-5α-spirostan-3β,25-diol, (20S,22S,25S)-5α-furostan-22,25-epoxy-3β,26-diol and (20S,22S,25R) -5α-furostan-22,25-epoxy-3β,26-diol, were isolated and characterized by spectroscopic (IR, ¹H NMR, ¹³C NMR, MS) methods.     

Three new benzophenone glycosides with MAO-A inhibitory activity from Hypericum thasium Griseb.

Purification of n-BuOH fraction from 80% ethanol extract of Hypericum thasium Griseb. resulted in the isolation of three new compounds 3′,4,5′-trihydroxy-6-methoxy-2-O-α-l-arabinosylbenzophenone (1), 3′,4,5′,6-tetrahydroxy-2-O-α-l-arabinosylbenzophenone (2), and 3′,4-dihydroxy-5′-methoxy-2-O-α-l-arabinosyl-6-O-β-d-xylosylbenzophenone (3) along with a known flavonoid glycoside quercetin-3-O-α-l-arabinofuranoside (4). The structures of the new compounds were elucidated by 1D and 2D NMR analysis as well as HRESIMS. The isolated compounds (1–4), as well as quercetin, and kaempferol previously isolated from EtOAc fraction were screened against MAO-A inhibitory activity. When tested against the MAO-A quercetin and kaempferol displayed IC₅₀ values of 19.6, and 17.5 μM, respectively. The IC₅₀ values for MAO-A inhibition by compounds (1–4) were 310.3, 111.2, 726.0, and 534.1 μM, respectively. Standard inhibitor (clorgyline) exhibited MAO-A inhibition with an IC₅₀ value of 0.5 μM.     

Two new flavonol glycosides from the leaves of Cleome viscosa L.

From the leaves of Cleome viscosa L., two new flavonol glycosides, named visconoside A (1) and visconoside B (2), together with six known flavonol glycosides, vincetoxicoside A (3), vincetoxicoside B (4), kaempferitrin (5), kaempferide 3-O-β-d-glucopyranoside 7-O-α-l-rhamnopyranoside (6), kaempferol 3-O-β-d-glucopyranoside 7-O-α-l-rhamnopyranoside (7), and isorhamnetin 3-O-β-d-glucopyranoside (8) were isolated by various chromatography methods. Its chemical structure was elucidated by IR, UV, HR-ESI-MS, NMR 1D and 2D experiments and compared with literatures.     

Steroidal saponins of Asparagus adscendens

From the methanol extract of the fruits of Asparagus adscendens sitosterol-β-d-glucoside, two spirostanol glycosides (asparanin A and B) and two furostanol glycosides (asparoside A and B) were isolated and characterized as 3-O-[β-d-glucopyranosyl (1→2)-β-d-glucopyranosyl]-(25S)-5β-spirostan-3β-ol, 3-O-{[β-d-glucopyranosyl(1→2)][α-l-rhamnopyranosyl(1→4)]-β-d-glucopyranosyl}-(25S)-5β-spirostan-3β-ol,3-O-{[β-d-glucopyranosyl(1→2)][α-l-rhamnopyranosyl(1→4)]-β-d-glucopyranosyl|} -26-O-(β- d-glucopyranosyl)-22α-methoxy-(25S)-5β-furostan-3β,26-diol and 3-O-{[β-d-glucopyranosyl(1→2)][α-l-rhamnopyranosyl(1→4)]-β-d-glucopyranosyl}-26-O-(β-d-glucopyranosyl)- 25S)-5β-furostan-3β,22α, 26-triol, respectively.