A new antiplasmodial coumarin from Toddalia asiatica roots

A new antiplasmodial coumarin, 5,7-dimethoxy-8-(3'-hydroxy-3'methyl-1'-butene)-coumarin (1), has been isolated from the roots of Toddalia asiatica. This finding supports the traditional use of this plant for the treatment of malaria.     

A new 7-oxygenated coumarin from Clausena suffruticosa

A new coumarin, 7-[(2′E,6′E)-7′-carboxy-5′(ζ)-hydroxy-3′-methylocta-2′,6′-dienyloxy]-coumarin, was isolated from the leaf of Clausena suffruticosa. Its structure was established by means of spectroscopic data analyses, including mass spectrometry and both 1D and 2D NMR spectroscopy.     

A new antifungal coumarin from Clausena excavata

A new γ-lactone coumarin, named as excavarin-A, showing antifungal activity was isolated from the leaves of Clausena excavata by bioassay guided fractionation method. The structure was elucidated by spectroscopic data analysis and identified as 7((2E)-4(4,5-dihydro-3-methylene-2-oxo-5-furanyl)-3-methylbut-2-enyloxy) coumarin. Minimum inhibitory concentration (MIC) was determined against fifteen fungal strains pathogenic against plants and human. The least MIC was recorded against the human pathogen, Candida tropicalis and the plant pathogens Rhizoctonia solani and Sclerotinia sclerotiorum. Antifungal activities against the human pathogens, Aspergillus fumigatus and Mucor circinelloides and plant pathogens, Colletotrichum gloeosporioides, Lasiodiplodia theobromae, Fusarium oxysporum and Rhizopus stolonifer were stronger than that of the standard antimicrobials.     

A new proaporphine alkaloid from Meconopsishorridula

A new proaporphine alkaloid, 8, 9-dihydroprooxocryptochine (1), together with three known alkaloids, was isolated from the aerial parts of Meconopsishorridula Hook. f. & Thomson (Papaveraceae), a traditional Tibetan medicine. The structure of 1 was determined by spectroscopic methods.     

A new triterpene glycoside from Centella erecta

A new (2α,3β)-23-sulphonyl-2,3-dihydroxyurs-12-en-28-oic acid O-α-l-rhamnopyranosyl-(1→4)-O-β-d-glucopyranosyl-(1→6)-O-β-d-glucopyranosyl ester (1) together with eighteen known compounds were isolated from Centella erecta (L.f.) Fern. Their structures were elucidated mainly by NMR and HRESIMS, as well as on comparison with the reported data.     

A new fungitoxic metabolite from Spiraea alpina Pall.

The fungitoxic metabolites of Spiraea alpina Pall. were identified using inhibition of Rhizoctonia solani, Gibberella zeae, Pyricularia oryzea and Exserohilum turcicum as an end-point. The major fungitoxic constituent of S. alpina was a new diacylated sugar, structurally elucidated as 6-O-(3′,4′-dihydroxy-2′-methylenbutyryl)-1-O-trans-cinnamoyl-β-D-glucopyranose. This compound could inhibit at 0.1 mg/ml Rhizoctonia solani and Exserohilum turcicum, 87.6% and 63.2%, respectively.     

A new diterpene from the leaves of Andrographis paniculata Nees

Phytochemical investigation of the ethanol extract of the leaves of Andrographis paniculata yielded one novel diterpene (13R, 14R) 3, 13, 14, 19-tetrahydroxy-ent-labda-8 (17), 11-dien-16, 15-olide 1 which has an uncommon cis-diol groups in the lactone moiety, and 3, 19-isopropylidene-14-deoxy-ent-labda-8 (17), 13-dien-16, 15-olide 2, probably an artifact diterpene, together with eight known diterpenoids 3–10. The structures of these compounds were determined on the basis of spectral methods. The structure and stereochemistry of 1 was confirmed by X-ray crystallographic analyses.     

A new natural azulene-type pigment from Oreocnide frutescens

A new natural red-purple azulene-type pigment, 1,1,6-trimethylazuleno[1,8-cd]pyran-3(1H)-one, named oreolactone (1), together with nine known compounds, scopoletin (2), pomolic acid (3), friedelin (4), 3β-friedelinol (5), 3α-friedelinol (6), stigmast-4-en-3-one (7), stigmast-4, 22-dien-3-one (8), β-sitosterol (9), and daucosterol (10), was isolated from the rhizomes of Oreocnide frutescens. The structures were elucidated on the basis of spectroscopic analysis.     

A new labdane diterpene from Vitex cauliflora Moldenke from the Madagascar rainforest

Fractionation of an antiplasmodial ethanolic extract from the aerial parts of Vitex cauliflora led to the isolation of the new labdane diterpene 1 together with the known triterpene uvaol. The structure of the new compound 1 was established as 3-oxo,15,17,18-triacetoxy-labda-7,13E-diene on the basis of spectroscopic data (1D and 2D NMR, MS).     

A new dihydrodibenzodioxinone from Hypericum x ‘Hidcote’

One new compound, 4-hydroxy-4a,7-dimethoxy-4,4a-dihydrodibenzo-p-dioxin-2(3H)-one (1), was isolated from the aerial parts of the hybrid Hypericum x ‘Hidcote’, together with 8 known compounds: caryophyllene-4,5-epoxide, quercetin, quercitrin, quercetin-3-O-β-D-galactopyranoside, epicatechin, betulinic acid methyl ester, β-sitosterol and β-sitosterol glucoside. The structure of the new compound, as well as its absolute configuration, was established by means of spectroscopic data analyses, including 2D NMR spectroscopy and X-ray structural analysis.     

A new dicoumarin and anticoagulant activity from Viola yedoensis Makino

A new dicoumarin, named as dimeresculetin (1), together with another dicoumarin, euphorbetin (2) and esculetin (3) were isolated from the ethyl acetate extract of the dried whole plants of Viola yedoensis Makino. The structure of 1 was elucidated as 7-hydroxy-6-[(6,7-dihydroxy-2-oxo-2H-1-benzopyran-5-yl)oxy]-2H-1-benzopyran-2-one on the basis of extensive NMR, as well as the other spectral analysis. Compounds 1–3 exhibited anticoagulant activities with respect to activated partial thromboplastin time (APTT), prothrombin time (PT) and thrombin time (TT).     

One new sesquiterpene from Saussurea laniceps

One new guaiane-type sesquiterpene (1) was isolated from Saussurea laniceps. The structure of the new compound was elucidated by spectroscopic data analysis. The immunomodulatory activity of compound 1 was evaluated. It was found that compound 1 showed significant inhibition for proliferation of murine T cells in vitro.     

Three new antibacterial active diarylheptanoids from Alpinia officinarum

Three new diarylheptanoids, together with ten known ones, were isolated from the ethanol extract from the rhizomes of Alpinia officinarum Hance. The structural identification of these compounds was mainly achieved by spectroscopic methods. The new compounds were elucidated as 7-(4″, 5″-dihydroxy-3″-methoxyphenyl)-1-phenyl -4-heptene-3-one (1), 1, 7-diphenyl-5-heptene-3-one (2) and 4-phenethyl-1, 7-diphenyl -1-heptene-3, 5-dione (3), respectively. All of the compounds showed antibacterial activity against Helicobactor pylori. Especially, the three new compounds showed strong antibacterial activity against Hp-Sydney strain 1 with the MIC values of 9–12 μg/mL, and against Hp-F44 with the MIC values of 25–30 μg/mL.     

Four new flavonoids from the leaves of Morus mongolica

Four new flavonoids (1–4) were isolated from the leaves of Morus mongolica. The structures were determined on the basis of the spectroscopic methods including UV, IR, HR-ESI-MS, 1D and 2D NMR.     

Photosynthetic characteristics of Fagus sylvatica and Quercus robur established for stand conversion from Picea abies

Efforts in Europe to convert Norway spruce (Picea abies) plantations to broadleaf or mixed broadleaf-conifer forests could be bolstered by an increased understanding of how artificial regeneration acclimates and functions under a range of Norway spruce stand conditions. We studied foliage characteristics and leaf-level photosynthesis on 7-year-old European beech (Fagus sylvatica) and pedunculate oak (Quercus robur) regeneration established in open patches and shelterwoods of a partially harvested Norway spruce plantation in southwestern Sweden. Both species exhibited morphological plasticity at the leaf level by developing leaf blades in patches with an average mass per unit area (LMA) 54% greater than of those in shelterwoods, and at the plant level by maintaining a leaf area ratio (LAR) in shelterwoods that was 78% greater than in patches. However, we observed interspecific differences in photosynthetic capacity relative to spruce canopy openness. Photosynthetic capacity (A₁₆₀₀, net photosynthesis at a photosynthetic photon flux density of 1600 μmol photons m⁻² s⁻¹) of beech in respect to the canopy gradient was best related to leaf mass, and declined substantially with increasing canopy openness primarily because leaf nitrogen (N) in this species decreased about 0.9 mg g⁻¹ with each 10% rise in canopy openness. In contrast, A₁₆₀₀ of oak showed a weak response to mass-based N, and furthermore the percentage of N remained constant in oak leaf tissues across the canopy gradient. Therefore, oak photosynthetic capacity along the canopy gradient was best related to leaf area, and increased as the spruce canopy thinned primarily because LMA rose 8.6 g m⁻² for each 10% increase in canopy openness. These findings support the premise that spruce stand structure regulates photosynthetic capacity of beech through processes that determine N status of this species; leaf N (mass basis) was greatest under relatively closed spruce canopies where leaves apparently acclimate by enhancing light harvesting mechanisms. Spruce stand structure regulates photosynthetic capacity of oak through processes that control LMA; LMA was greatest under open spruce canopies of high light availability where leaves apparently acclimate by enhancing CO₂ fixation mechanisms.     

A new dilactone from the seeds of Gaultheria yunnanensis

Gaultheriadiolide (1), a new compound, together with the known dauosterol (2), ginkgetin (3), myricetin (4), 6-ethyl-5-hydroxy-2,7-dimethoxy-1,4-naphthoquinone (5), ursolic acid (6), methyl salicylate 2-O-β-d-xylosyl(1→6)β-d-glucopyranoside (7), and methyl salicylate 2-O-β-d-glucopyranoside (8) were isolated from Gaultheria yunnanensis. The structure was elucidated on the basic of spectral analysis, especially 1D and 2D NMR. Primary bioassays showed that compound 1 had medium cytotoxic activity against HEp-2 and HepG2 Cells, with IC₅₀ of 23.337 μM and 29.4497 μM, respectively.     

A new cytotoxic 1-azaanthraquinone from the stems of Goniothalamus laoticus

A new 1-azaanthraquinone, named laoticuzanone A (1), and a synthetically known 3-methyl-1H-1-azaanthracene-2,9,10-trione (2), together with four known compounds, Griffithazanone A (3), methyl sinapate (4), methyl p-coumarate (5), and p-hydroxyphenylethyl p-coumarate (6) were isolated from the stems of Goniothalamus laoticus. Their structures were established on the basis of spectroscopic data as well as comparisons with the previous literature data. Compound 1 showed the highest cytotoxicity against KB and HeLa cells with IC₅₀ values of 0.68 and 0.50 μg/ml, respectively.     

Humarain: A new dimeric gallic acid glycoside from Punica granatum L. bark

A new dimeric gallic acid glycoside named Humarain (1) was isolated from stem bark of Punica granatum. The structure of the compound was determined by spectroscopic data including 1D and 2D NMR spectral analysis.     

New coumarin glycosides from the leaves of Diospyros crassiflora (Hiern)

Two new 5-methylcoumarin glycosides named diosfeboside A (1) and B (2) and five known compounds namely kaempferol 3-O-α-l-rhamnopyranosyl-(1→2)-β-d-glucopyranoside (3), ursolic acid (4), betulinic acid (5), stigmasterol (6) and stigmasterol 3-O-β-d-glucopyranoside (7) were isolated from the leaves of Diospyros crassiflora (Hiern). Their structures were established through interpretation of 1 and 2D NMR, mass spectra analysis and comparison with reported data. In vitro cytotoxic activity of the new compounds against human carcinoma cell lines (HL-60, Bel-7402, BGC-823, and KB) was evaluated and no cytotoxicity was observed for each of them.     

Two new iridoid glucosides from Hedyotis diffusa

Two new iridoid glucosides, named diffusosides A and B, were isolated from the aerial part of Hedyotis diffusa Willd. Their structures were elucidated by 1D-, 2D-NMR spectroscopic analysis and HRESIMS. These two compounds showed no cytotoxic activity against SMMC-7721, SW480, SW620, Bel7402, and HepG2 cells.