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.     

Two new minor cyclopeptides from Sagina japonica (Caryophyllaceae)

Two new minor cyclopeptides, named japonicin A (1), japonicin B (2), were isolated from the whole plants of Sagina japonica (Caryophyllaceae). Their structures were determined as cyclo-(Pro¹-Pro²-Leu²-Leu¹-Phe²-Pro³-Gly-Ser-Phe¹) (1) and cyclo-(Pro¹-Ile-Tyr-Asp-Pro²-Phe²-Pro³-Phe¹) (2) on the basis of spectroscopic data, especially by two-dimension NMR technologies.     

Two new triterpene saponins from the aerial parts of Paraquilegia microphylla

Two new triterpene saponins, paraquinosides A (1) and B (2) were isolated from the aerial parts of Paraquilegia microphylla (Royle) Dromm. et Hutch, a Tibetan ethnic medicine distributed in the Qinghai–Tibet Plateau. On the basis of 1D and 2D NMR evidence, their structure was elucidated as 3-O-α-L-rhamnopyranosyl (1→2)-β-D-glucopyranosyl-15-dehydroxyl-16-O-methyl-24, 25-deoxy-26-hydroxylshengmanol-26-O-β-D-glucopyranoside (1) and 3-O-α-L-Rhamnopyranosyl (1→2)-[β-D-glucopyranosyl(1→3)]-β-D-glucopyranosyl-15-dehydroxyl-16-O-methyl-24, 25-deoxy-26-hydroxylshengmanol-26-O-β-D- glucopyranoside (2), respectively.     

A new coumarin from Sarcandra glabra

Sarcandracoumarin (1), the first coumarin having a 1-phenylethyl substituent at the C-3 position, was isolated along with eleven known phenolic compounds from the water extract of Sarcandra glabra. Its structure was elucidated on the basis of spectroscopic data. Compound 1 exhibited moderate or weak cytotoxicity against several tumor cell lines.     

Two new benzofuran derivatives with anti-inflammatory activity from Liriope spicata var. prolifera

Two new benzofuran derivatives, 2-(4′-hydroxybenzyl)-5,6-methylenedioxy-benzofuran () and 2-(4′-hydroxybenzoyl)-5,6-methylenedioxy-benzofuran (), along with 8 known compounds were isolated from 60% EtOH extract of the fibrous roots of Liriope spicata var. prolifera. Their structures were elucidated on the basis of extensive spectroscopic analysis. In an in vitro bioactive assay, the two new benzofuran derivatives showed anti-inflammatory activity. Compounds 1 and 2 exhibited significant inhibitory activity against neutrophil respiratory burst stimulated by phorbol 12-myristate 13-acetate (PMA) with IC₅₀ value of 4.15 ± 0.07 and 5.96 ± 0.37 μM, respectively.     

Two new chamigrane metabolites from fermentation broth of Steccherinum ochraceum

Two new chamigrane-type metabolites named steperoxides C (1) and D (2) were isolated from the basidiomycetes Steccherinum ochraceum. The structures of 1 and 2 were established on the basis of spectral methods (MS, IR, ID and 2D NMR experiments). Compounds 2 showed significant antimicrobial activity against Staphylococcus aureus at 10 and 5 μg/disk.     

Two new cytotoxic isomeric indole alkaloids from the roots of Nauclea orientalis

A pair of new isomeric indole alkaloids, naucleaorals A (1) and B (2) were isolated from the roots of Nauclea orientalis. The structures of compounds 1 and 2 were fully characterized using spectroscopic data, and were tested for their cytotoxicity (HeLa and KB cells) and antimalarial activity. Compound 1 showed significant cytotoxicity to HeLa cells with an IC₅₀ value of 4.0 µg/mL, while compound 2 exhibited very modest cytotoxicity to both cell lines with IC₅₀ values of 7.8 and 9.5 µg/mL, respectively. Both compounds proved to be inactive in antimalarial assays (IC₅₀ > 10.00 µg/mL).     

Two new cerebrosides from the pollen of Typha angustifolia

Two new cerebrosides, 1-O-(β-d-glucopyranosyloxy)-(2S,3S,4R,8Z)-2-[(2′R)-2′-hydroxytricosanoylamino]-8-nonadecene-3,4-diol (1) and 1-O-(β-d-glucopyranosyloxy)-(2S,3R,4E,8Z)-2-[(2′R)-2′-hydroxynonadecanoylamino]-4,13-nonadecene-3-diol (2), were isolated from the pollen of Typha angustifolia. Their structures were elucidated by chemical and spectral means. This is the first report on the occurrence of cerebroside in Typha (Typhaceae). Compounds 1 and 2 exhibited effect on the proliferation of cultured vascular smooth muscle cell (VSMCs) induced by fatal bovine serum (FBS).     

Two new bufadienolides from the rhizomes of Helleborus thibetanus Franch

Two new bufadienolides, named tigencaoside A(1) and tigencaoside B(2), were isolated from the rhizomes of Helleborus thibetanus Franch., along with two known bufadienolides, hellebrigenin (3) and 5β,14β-dihydroxy-19-oxo-3β-[(α-L-rhamnopyranosyl)oxy]bufa-20,22-dienolide (4). Their structures were elucidated on the basis of extensive spectroscopic analysis. Two new compounds were evaluated for their cytotoxic activities against four strains of cultured tumor cells.     

Two new bisindole alkaloids from the seeds of Strychnos nux-vomica

The reinvestigation of Strychnos nux-vomica resulted in the isolation of two colorless monoquaternary bisindole alkaloids from the seeds. The structures of the two new compounds named 4-N-hydroxymethyl strychnidin-17-acetic acid (1) and 10, 11-dimethoxy-4-N-hydroxymethyl strychnidin-17-acetic acid (2), were defined by detailed spectral analyses, especially ¹H NMR, ¹³C NMR, DEPT, HSQC, ¹H NMR–¹H NMR, NOESY, HMBC and TOF-MS.     

Two new prenylated xanthones and a new prenylated tetrahydroxanthone from the pericarp of Garcinia mangostana

Two new prenylated xanthones and a new prenylated tetrahydroxanthone, garcimangosxanthone A–C (1–3), along with fourteen known xanthones were isolated from the pericarp of Garcinia mangostana. Their structures were elucidated on the basis of spectroscopic data. Compounds 1 and 2 exhibited in vitro cytotoxicity against A549, LAC and A375 cell lines with IC₅₀ values of 5.7–24.9 μM, which were comparable to those of doxorubicin.     

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.     

Two phenolic glycosides from Curculigo orchioides Gaertn

One new glycoside derivative from syringic acid and one new phenol glycoside, curculigoside E (1) and orchioside D (2), were isolated and characterized from the rootstock of Curculigo orchioides collected in the Nawalparasi District (Nepal). The structures of the new isolated compounds were elucidated by means of spectroscopic methods such as 1D, 2D NMR and MS.     

Two 22S-solanidine-type steroidal alkaloids from Fritillaria anhuiensis

Phytochemical investigation of the fresh bulbs of Fritillaria anhuiensis S. C. Chen et S. E. Yin, resulted in the isolation of a known steroidal alkaloid solanidine of (22S,25S)-solanid-5-en-3β-ol (1), which has never yet been found as a natural substance, and of a new steroidal alkaloid (22S,25S)-solanid-5,20(21)-dien-3β-ol. Compounds 1 and 2 were the first solanidine-type alkaloids with 22-S configuration discovered from nature. Their structures were elucidated based on spectroscopic analysis, including 1D and 2D NMR experiments.     

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.     

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 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.