Sesquiterpenoids and norsesquiterpenoids from three liverworts

Six new sesquiterpenoids and two new norsesquiterpenoids were isolated from the essential oils of three liverworts. The isolated compounds include (+)-eudesma-4,11-dien-8α-ol from the liverwort Diplophyllum albicans, (−)-4β,5β-diacetoxygymnomitr-3(15)-ene, (+)-5β-acetoxygymnomitr-3(15)-ene, (−)-15-acetoxygymnomitr-3-ene, (−)-3β,15β-epoxy-4β-acetoxygymnomitrane, and (−)-3α,15α-epoxy-4β-acetoxygymnomitrane from Marsupella emarginata, and (+)-1,2,3,6-tetrahydro-1,4-dimethylazulene and (−)-2,3,3a,4,5,6-hexahydro-1,4-dimethylazulen-4-ol from Barbilophozia floerkei. These compounds were isolated by a combination of different chromatographic techniques, and their structures were determined by extensive spectroscopic studies (MS, ¹H, ¹³C, and 2D NMR) and chemical transformations using enantioselective GC.     

A new triterpene from Salvia xanthocheila Boiss

From the chloroform extract of the aerial parts of Salvia xanthocheila, one new triterpene, together with two known diterpenes, two known flavonoids and a phytosterol was isolated. On the basis of comprehensive spectroscopic analyses, including electron ionisation mass spectra, 1H-NMR, 13C-NMR, 1-D nuclear Overhauser effect, distortionless enchancement by polarisation transfer, H,H correlation spectroscopy, heteronuclear multiple quantum coherence, rotating frame Overhauser enhancement spectroscopy spectra and comparison with spectral data of known compounds, the structure of new compounds was established as 1β,3β-dihydroxy-olean-9(11),12-dienyl (1). The five known compounds (2-6) were 7α-acetoxyroyleanone, taxodione, salvigenin, apigenin-7,4'-dimethyl ether and β-sitosterol, respectively. These known structures are isolated from the aerial parts of S. xanthocheila for the first time.     

Antioxidant, anti-glycation and anti-inflammatory activities of phenolic constituents from Cordia sinensis

Nine compounds have been isolated from the ethyl acetate soluble fraction of C. sinensis, namely protocatechuic acid (1), trans-caffeic acid (2), methyl rosmarinate (3), rosmarinic acid (4), kaempferide-3-O-β-D-glucopyranoside (5), kaempferol-3-O-β-D-glucopyranoside (6), quercetin-3-O-β-D-glucopyranoside (7), kaempferide-3-O-α-L-rhamnopyranosyl (1→6)-β-D-glucopyranoside (8) and kaempferol-3-O-α-L-rhamno-pyranosyl (1→6)-β-D-glucopyranoside (9), all reported for the first time from this species. The structures of these compounds were deduced on the basis of spectroscopic studies, including 1D and 2D NMR techniques. Compounds 1-9 were investigated for biological activity and showed significant anti-inflammatory activity in the carrageen induced rat paw edema test. The antioxidant activities of isolated compounds 1-9 were evaluated by the DPPH radical scavenging test, and compounds 1, 2, 4 and 7-9 exhibited marked scavenging activity compared to the standard BHA. These compounds were further studied for their anti-glycation properties and some compounds showed significant anti-glycation inhibitory activity. The purity of compounds 2-5, 8 and 9 was confirmed by HPLC. The implications of these results for the chemotaxonomic studies of the genus Cordia have also been discussed.     

Quinquenoside F₆, a new triterpenoid saponin from the fruits of Panax quinquefolium L

Six triterpenoid saponins, including one new compound, quinquenoside F?(1), and five known compounds ginsenoside Re, ginsenoside Rg?, ginsenoside Rg?, ginsenoside Rh? and pseudo-ginsenoside F??, were isolated from the fruits of Panax quinquefolium L., and the structure of compound 1 was elucidated as 6-O-β-d-glucopyranosyl-20-O-[α-l-arabino- furanosyl-(1-6)-β-d-glucopyranosyl]-dammar-24-ene-3β, 6α, 12β, 20S-tetraol by the combination of the analysis of spectroscopic data and chemical evidences. The complete signal assignments of the six compounds were carried out by means of 2D NMR spectral analysis.     

Proanthocyanidins ofPolygonum corarium. II

Eight proanthocyanidins have been isolated from the roots ofPolygonum coriarum. The structures of two dimers, two trimers, including an acylglycosylated one, a tetramer, and three oligomers have been determined. All the compounds isolated were polymers and copolymers of (-)epigallocatechin, (-)epigallocatechin gallate and (-)epicatechin with C-4β→C-8 interflavan bonds.     

A new isorhamnetin glycoside and other phenolic compounds from Callianthemum taipaicum

A new flavonol glycoside together with five known phenolic compounds were isolated from the whole herb of Callianthemum taipaicum. The compounds were identified as isorhamnetin-3-O-α-L-arabinoside-7-O-β-D-glucoside (1), isorhamnetin-3-O-β-D-glucoside (2), dibutyl phthalate (3), (+)-1-hydroxylpinoresinol-4'-β-D-glucoside (4), pinoresinol-4'-O-β-D-glucoside (5) and 2-phenylethyl-β-primeveroside (6). Compound 1 was identified as a new flavonol glycoside. The compound 6 was isolated for the first time as natural product. All compounds were isolated for the first time from the Callianthemum genus. Furthermore, the 2D-NMR data of the four known compounds 2-5 are given for the first time in this paper. All the structures were identified on the basis of detailed spectral analysis. The compounds 1 and 4 exhibited certain antifungal activity.     

Anti-inflammatory and antioxidant components from Hygroryza aristata

Twenty-six known compounds and two new compounds, including a new lignan, (7S*,8R*,7'R*,8'S*)-icariol A?-9-O-β-xylopyranoside (1), and a new indole alkaloid, hygarine (2), were isolated from the extracts of Hygroryza aristata (Gramineae). The structures of all compounds were elucidated on the basis of NMR spectral analysis. The compounds (-)-epigallocatechin-3-O-gallate (4) and (-)-epicatechin-3-O-gallate (5) possess free radical scavenging activities and compound 1 could inhibit superoxide anion generation and elastase release by fMLP/CB-induced human neutrophils with IC?? values of 19.33 ± 0.86 and 24.14 ± 1.59 μM, respectively.     

Antioxidant secondary metabolites from Geranium lasiopus Boiss. & Heldr

Chromatographic studies on the EtOAc soluble portion of the MeOH extract of Geranium lasiopus led to the isolation of eight flavonoids (kaempferol (1), quercetin (2), quercetin 3-O-β-glucopyranoside (3), quercetin 3-O-β-galactopyranoside (4), kaempferol 3-O-α-rhamnopyranosyl-(1?→?6)-β-glucopyranoside (5), quercetin 3-O-α-rhamnopyranosyl-(1?→?6)-β-glucopyranoside (6), kaempferol 3-O-α-rhamnopyranosyl-(1?→?2)-β-glucopyranoside (7) and quercetin 3-O-α-rhamnopyranosyl-(1?→?2)-β-glucopyranoside (8)), two simple phenolic compounds (gallic acid (9) and its methyl ester (10)) and a hydrolysable tannin (pusilagin (11)). The structures of the compounds were elucidated by 1- and 2-dimensional NMR techniques ((1)H, (13)C, COSY, HMBC, HMQC) and ESI-TOF-MS spectrometry. Inhibitory effects on H(2)O(2)-induced lipid peroxidation in human red blood cells of the different extracts of G. lasiopus, as well as isolated compounds, were investigated. All tested compounds showed comparable or higher activity than that of ascorbic acid and trolox.     

A straightforward synthesis of (E)-δ-alkenyl-β,γ-unsaturated δ-lactones by a tandem ring-closing/cross-coupling metathesis process

The access to (E)-δ-alkenyl-β,γ-unsaturated δ-lactones starting from 3-O-(1,4-pentadienyl) 3-butenoate has been investigated by using a tandem process including two different metathesis reactions. By this way, new structures, isomers of natural compounds like argentilactone, were isolated in good yields. Reconjugation of the internal CC bond can be achieved under basic conditions to give α-pyrones.     

Phenolic compounds from the aerial parts of Diplomorpha canescens

One new C-methyl flavanone glucoside, farrerol 4'-O-β-D-glucopyranoside (1) was isolated from the aerial parts of Diplomorpha canescens (MEISN.) C. A. MEYER. Fourteen known phenolic compounds such as farrerol (2), luteolin 7-methyl ether 5-O-β-D-glucopyranoside (3), (-)-pinoresinol (4), (-)-lariciresinol (5), (-)-dihydrosesamin (6), (±)-dehydrodiconiferyl alcohol (7), rutarensin (8), umbelliferone (9), coniferyl aldehyde (10), sinapyl aldehyde (11), p-coumaric acid methyl ester (12), p-hydroxybenzaldehyde (13), p-hydroxyacetophenone (14) and syringaldehyde (15) were also isolated for the first time from this plant. Structure of 1 was determined on the basis of spectroscopic data including two dimensional (2D)-NMR, circular dichroism (CD) and by the application of Klyne's rule.     

A new highly hydroxylated triterpene from Salvia atropatana Bunge

One new triterpenoid olean-18-ene-1β, 2α, 3β-triol (1) along with four known compounds were isolated from the chloroform extract of the aerial part of Salvia atropatana Bunge. The known compounds were two flavonoids, 5-hydroxy-7,4'-dimethoxyflavone (2) and 5-hydroxy-6,7,4'-trimethoxyflavone (3), an abietane-type diterpene namely taxodione (4) and a phytosterol namely γ -sitosterol (5). The structure of (1) was elucidated by comprehensive spectroscopic analysis including electron ionization-mass spectra (EI-MS), (1)H NMR, (13)C NMR, distortionless enhancement by polarization transfer (DEPT), H,H correlation spectroscopy (COSY), heteronuclear multiple quantum coherence (HMQC) and heteronuclear multiple bond correlation (HMBC). The structure of known compounds 2-5 were identified by comparison of their spectral data with those reported in the literature.     

Antioxidant and anti-nitric oxide components from Quercus glauca

From the ethanolic extract of Quercus glauca, two new lignans, (+)-5'-methoxyisolariciresinol-9'-O-α-L-rhamnopyranoside (1) and (7R,8S)-dihydrodehydrodiconiferyl alcohol 4-β-D-xyloside (2), along with fourteen known compounds including four lignanoids (3-6), five triterpenoids (7-11), two flavonoids (12, 13), two aromatics (14, 15), and one steroid (16) were isolated. The structures of the new compounds were elucidated on the basis of spectroscopic analysis. Moreover, compounds 9 and 14 strongly inhibited nitric oxide (NO) production with IC50 values of 8.25 and 14.04?μM, respectively, and compounds 1, 4-6, 14, and 15 showed moderate antioxidant activities.     

Aristolactams and Alkamides of Aristolochia gigantea

A new aristolactam, aristolactam 9-O-β-D-glucopyranosyl-(1→2)-β-D-glucoside, and two alkamides, N-cis- and N-trans-p-coumaroyl-3-O-methyldopamine, were isolated from stems of Aristolochia gigantea, together with the known compounds allantoin, E-nerolidol, β-sitosterol, (+)-kobusin, (+)-eudesmin, trans-N-feruloyltyramine, trans-N-coumaroyltyramine, trans-N-feruloyl-3-O-methyldopamine, aristolactam Ia-N-β-D-glucoside, aristolactam Ia 8-β-D-glucoside, aristolactam IIIa, and magnoflorine. Their structures were determined by spectroscopic analyses.     

A new glycoside from Polygala tenuifolia Willd

A new tdterpenoid glycoside, 3-β-O-β-D-glucopyranosyl presenegenin 28-O-α-L-arabipyranosyl（1 → 3）-6-β- xylopyranosyl（1 → 4）-[β-D-apiofuranosyl（1 → 3）]-Ct-L-rhamnopyranosyl（1 → 2）-[α-L-rhamnopyranosyl（1 → 3）]-β-D-fucopyranosyl ester （1） was isolated from the Polygala tenuifolia Willd., together with two known saponins, including polygalasaponinXXIV （2） and polygalasaponinXXVIII （3）. The structure of new compound was elucidated by spectroscopic methods.     

A new isoflavone glycoside from Pueraria alopecuroides

A new isoflavone glycoside, (?)-tuberosin-3-O-β-D-glucopyranoside (1), along with 10 known compounds 1a-10, was isolated from Pueraria alopecuroides. Their structures were determined on the basis of spectral data including 1D and 2D NMR and HREIMS. These compounds were isolated from this plant for the first time.     

Flavonol glycosides from Epimedium pubescens

Five new flavonol glycosides (1, 3, 5-7) were isolated from the aerial parts of Epimedium pubescens Maxim., along with two known compounds, sagittasine C (2) and 4',5-dihydroxyl-8-(3,3-dimethylallyl)-flavonol 3-O-[β-D-xylopyranosyl(1→3)-4-O-acetyl-α-L-rhamnopyranoside]-7-O-β-D-glucopyranoside (4). The structures were elucidated on the basis of their 1D-, 2D-NMR, MS, UV and IR spectra data.     

Phenolic constituents of the aerial parts of Impatiens glandulifera Royle (Balsaminaceae) and their antioxidant activities

As a continuation of investigating Impatiens L. genus, eight flavonoids, eriodyctiol, eriodyctiol 7-O-β-?-glucoside, kaempferol 3-O-β-?-glucoside, kaempferol 3-O-β-?-galactoside, kaempferol 3-rhamnosyl-di-glucoside, kaempferol 3-O-β-?-rutinoside, quercetin 3-O-β-?-glucoside and quercetin 3-O-β-?-galactoside, two phenolic acids – p-hydroxybenzoic acid and protocatechuic acid, and 2-methoxynaphthalene-1,4-dione were isolated from the aerial parts of I. glandulifera collected in Poland. The structures of the compounds were established by analysis of their spectroscopic (¹H and ¹³C NMR) and spectrometric (MS) data, as well as by comparison of these with those reported in the literature. Quercetin 3-O-β-?-glucoside, kaempferol 3-O-β-?-galactoside and kaempferol 3-O-β-?-rutinoside were isolated for the first time from the investigated taxon. In addition, the antioxidant activities in different tests of all obtained compounds were evaluated. The results clearly showed that among analyzed constituents, quercetin 3-O-β-?-glucoside exhibited antioxidant activity comparable or better than ascorbic acid and Trolox which were used as a positive control.     

Three steroids with unique structural feature of 5β-Spirostan-1β,3β,17α-trihydroxyl from Reineckia carnea

A new spirostanol sapogenin and two spirostanol saponins, tentatively named reineckiagenin A (1), reineckiagenoside A (2), and reineckiagenoside B (3), were isolated from the whole plant of Reineckia carnea. By detailed analysis of their 1D and 2D NMR spectra, chemical methods, and by comparison with spectra data of known compounds, the structures of the new steroids were determined to be 25(S)-5β-spirostan-1β,3β,17α-triol (1), 25(S)-5β-spirostan-1β,3β,17α-triol 1-O-β-D-xylopyranoside (2), 25(S)-5β-spirostan-1β,3β,17α-triol 1-O-α-L-rhamnopyranosyl-(1→2)-β-D-xylopyranoside (3). Compounds 1, 2, and 3 are the first naturally occurring steroids with unique structural feature of 5β-spirostan-1β,3β,17α-trihydroxyl.     

Pyromeconic acid derivatives from Conyza canadnsis(L.) Cronq

A new pyromeconic acid derivative,pyromeconic acid-3-O-β-D-glucopyranoside-3′-(O-β-D-glucopyranoside)-6′-(O-4″-hydroxybenzoate) (1),along with two known ones,were isolated from the whole plants of Conyza canadensis.Their structures were elucidated based on the analysis of their spectroscopic data.The in vitro antibacterial testing results showed that all of these three compounds were inactive towards two bacterial strains,Escherichia coli and Staphyloccocus aureus.     

Cytotoxic compounds from the leaves of Gaillardia aristata Pursh. growing in Egypt

Ten compounds, neopulchellin (1), 6α- hydroxyneopulchellin (2), β-sitosterol-3-O-β-D-glucoside (3), apigenin (4), quercitin (5), eupafolin (6), kaempferol-3-methoxy-7-O-α-L-rhamnoside (7), apigenin-7-O-β-D-glucopyranoside (8), α-amyrin (9) and β-sitosterol (10), were isolated from the leaves of Gaillardia aristata by applying bioassay guided fractionation. The cytotoxicity was traced against two human cancer cell lines (breast (MCF7) and colon (HCT116)). The highest cytotoxicity was revealed by compounds 1 and 2 (isolated from chloroform extract); with IC(50) values of 0.43, 0.32?μg?mL(-1) against MCF7 and 0.46, 0.34?μg?mL(-1) against HCT116, respectively. Compounds 9 and 10 (isolated from the n-hexane extract) exhibited lower IC(50) values of 3.05, 2.35?μg?mL(-1) against MCF7 and 3.05, 2.35?μg?mL(-1) against HCT116, respectively, while compounds 4-7 obtained from the ethyl acetate extract revealed the lowest cytotoxicity. Identification of the aforementioned compounds was carried out on the basis of their physico-chemical properties and spectral analysis (UV, EI/MS, 1D and 2D).