Phenolics of Moringa oleifera leaves

Five flavonol glycosides characterised as kaempferide 3-O-(2',3'-diacetylglucoside), kaempferide 3-O-(2'-O-galloylrhamnoside), kaempferide 3-O-(2'-O-galloylrutinoside)-7-O-alpha-rhamnoside, kaempferol 3-O-[beta-glucosyl-(1 --> 2)]-[alpha-rhamnosyl-(1 --> 6)]-beta-glucoside-7-O-alpha-rhamnoside and kaempferol 3-O-[alpha-rhamnosyl-(1 --> 2)]-[alpha-rhamnosyl-(1 --> 4)]-beta-glucoside-7-O-alpha-rhamnoside together with benzoic acid 4-O-beta-glucoside, benzoic acid 4-O-alpha-rhamnosyl-(1 --> 2)-beta-glucoside and benzaldehyde 4-O-beta-glucoside have been isolated from methanolic extract of Moringa oleifera leaves. Also obtained from the same extract were known compounds, kaempferol 3-O-alpha-rhamnoside, kaempferol, syringic acid, gallic acid, rutin and quercetin 3-O-beta-glucoside. Their structures were determined using spectroscopic methods as well as comparison with data from known compounds.     

Three new 3-benzylbenzofuran-2-one derivatives from Homalium brachybotrys (Flacourtiaceae/Salicaceae s. l.)

Eight phenolic compounds, including two mixtures of two compounds, were isolated from the ethyl acetate extract of leaves and stems of Homalium brachybotrys. They were identified on the basis of spectroscopic data as quercetin-3-O-beta-glucopyranoside, luteolin-7-O-beta-glucopyranoside, 5,6-dihydro-6-beta-glucopyranosyloxy-3-(hydroxyphenyl-methyl)-2(4H)-benzofuranone (cochinolide 6-O-beta-glucopyranoside) (1), 2-(6-benzoyl-beta-glucopyranosyloxy)-5-hydroxybenzyl alcohol (poliothrysoside) (2), 2-(beta-glucopyranosyloxy)-5-hydroxybenzyl alcohol (salirepin) (3), 4,5-dihydro-7a-beta-glucopyranosyloxy-3-(hydroxyphenylmethyl)-2(7aH)-benzofuranone (isocochinolide-7a-O-beta-glucopyranoside) (4), 5,6-dihydro-3-(hydroxyphenylmethyl)-2(4H)-benzofuranone (6-deoxycochinolide) (5) and 3-benzylidine-6-hydroxy-2-benzofuranone (1'deoxy-4,5,6-dehydrocochinolide) (6). Benzofuranones (4), (5) and (6) are new natural products. The compounds isolated support the argument that Homalium is best placed in the Salicaceae s.l.     

New acylated anthocyanins and other flavonoids from the red flowers of Clematis cultivars

Six new acylated cyanidin glycosides, cyanidin 3-O-beta-(2'-E-caffeoylglucopyranosyl)-(1 --> 2)-O-beta-galactopyranoside (1), cyanidin 3-O-beta-(2'-E-caffeoylglucopyranosyl)-(1 --> 2)-O-beta-(6'-malonylgalactopyranoside) (2), cyanidin 3-O-beta-(2'-E-caffeoylglucopyranosyl)-(1 --> 2)-O-beta-(6'-succinylgalactopyranoside) (3), cyanidin 3-O-beta-(2'-E-caffeoylglucopyranosyl)-(1 --> 2)-O-beta-galactopyranoside-3'- O-beta-glucuronopyranoside (4), cyanidin 3-O-beta-(2'-E-caffeoylglucopyranosyl)-(1 --> 2)-O-beta-(6'-malonylgalactopyranoside)-3'-O-beta-glucuronopyranoside (5), and cyanidin 3-O-beta-(2'-E-feruloylglucopyranosyl)-(1 --> 2)-O-beta-(6'-malonylgalactoside)-3' -O-beta-glucuronopyranoside (6), were isolated from the red flowers of two Clematis cultivars, 'Niobe'and 'Madame Julia Correvon'. The chemical structures of the isolated anthocyanins were determined by UV, LC-MS, HPLC, TLC, characterization of hydrolysates, and 1H and 13C NMR spectroscopy, including H-H COSY, C-H COSY, HMBC, HMQC and NOESY. The last three anthocyanins were widely distributed in 37 red flower Clematis cultivars. On the other hand, the first three compounds were found only in two cultivars. Five known flavonol glycosides, kaempferol 3-O-glucoside, kaempferol 3-O-rutinoside, quercetin 3-O-galactoside, quercetin 3-O-glucoside and quercetin 3-O-rutinoside, were isolated from the flowers of'Madame Julia Correvon'.     

Kaempferol glycosides in the flowers of carnation and their contribution to the creamy white flower color

Three flavonol glycosides were isolated from the flowers of carnation cultivars 'White Wink' and 'Honey Moon'. They were identified from their UV, MS, 1H and 13C NMR spectra as kaempferol 3-O-neohesperidoside, kaempferol 3-O-sophoroside and kaempferol 3-O-glucosyl-(1 --> 2)-[rhamnosyl-(1 --> 6)-glucoside]. Referring to previous reports, flavonols occurring in carnation flowers are characterized as kaempferol 3-O-glucosides with additional sugars binding at the 2 and/or 6-positions of the glucose. The kaempferol glycoside contents of a nearly pure white flower and some creamy white flower lines were compared. Although the major glycoside was different in each line, the total kaempferol contents of the creamy white lines were from 5.9 to 20.9 times higher than the pure white line. Thus, in carnations, kaempferol glycosides surely contribute to the creamy tone of white flowers.     

Reactive oxygen species scavenging activity of flavone glycosides from Melilotus neapolitana

One new and six known flavone glycosides were isolated from the MeOH extract of Melilotus neapolitana Ten. The new compound, identified as 7-O-beta-D-glucopyranosyloxy-4',5-dihydroxy-3-[O-alpha-L-rhamnopyranosyl-(1-->6)-3-O-beta-D-glucopyranosyloxy]flavone (1) by 1D and 2D NMR techniques and mass spectra, was isolated along with kaempferol-3-O-rutinoside (2), kaempferol-3-O-glucoside (3), rutin (4), quercetin-3-O-glucoside (5), isorhamnetin-3-O-rutinoside (6), and isorhamnetin-3-O-glucoside (7). The antioxidant and radical scavenging activities of these compounds and the whole crude methanol extract were evaluated. The organic extract can inhibit MDA marker's synthesis by 57%. All the metabolites displayed good reducing power, with the kaempferol (2,3) and isorhamnetin derivatives (6,7) being less active than the corresponding quercetin derivatives 4,5.     

Prolyl endopeptidase inhibitors from the underground part of Rhodiola sachalinensis

The methanolic extract of the underground part of Rhodiola sachalinensis was found to show inhibitory activity on prolyl endopeptidase (PEP, EC. 3.4.21.26), an enzyme that plays a role in the metabolism of proline-containing neuropeptidase which is recognized to be involved in learning and memory. From the MeOH extract, five new monoterpenoids named sachalinols A (24), B (25) and C (26) and sachalinosides A (23) and B (27) were isolated, together with twenty-two known compounds, gallic acid (1), trans-p-hydroxycinnamic acid (2), p-tyrosol (3), salidroside (4), 6n-O-galloylsalidroside (5), benzyl beta-D-glucopyranoside (6), 2-phenylethyl beta-D-glucopyranoside (7), trans-cinnamyl beta-D-glucopyranoside (8), rosarin (9), rhodiocyanoside A (10), lotaustralin (11), octyl beta-D-glucopyranoside (12), 1,2,3,6-tetra-O-galloyl-beta-D-glucose (13), 1,2,3,4,6-penta-O-galloyl-beta-D-glucose (14), kaempferol (15), kaempferol 3-O-beta-D-xylofuranosyl(1-->2)-beta-D-glucopyranoside (16), kaempferol 3-O-beta-D-glucopyranosyl(1-->2)-beta-D-glucopyranoside (17), rhodionin (18), rhodiosin (19), (-)-epigallocatechin (20), 3-O-galloylepigallocatechin-(4-->8)-epigallocatechin 3-O-gallate (21) and rosiridin (22). Among these, nineteen compounds other than 3, 4 and 9 have been isolated for the first time from R. sachalinensis, and six (6, 8, 13, 16, 17, 20) are isolated from Rhodiola plants for the first time. Among them, six compounds (13, 14, 18, 19, 21, 22) showed noncompetitive inhibition against Flavobacterium PEP, with an IC50 of 0.025, 0.17, 22, 41, 0.44 and 84 microM, respectively.     

Anti-stress constituents of Evolvulus alsinoides: an ayurvedic crude drug

Bioactivity-guided purification of n-BuOH soluble fraction from the ethanol extract of Evolvulus alsinoides resulted in the isolation of two new compounds, 2,3,4-trihydroxy-3-methylbutyl 3-[3-hydroxy-4-(2,3,4-trihydroxy-2-methylbutoxy)-phenyl]-2-propenoate (1) and 1,3-di-O-caffeoyl quinic acid methyl ester (2) along with six known compounds, caffeic acid (3), 6-methoxy-7-O-beta-glucopyranoside coumarin (4), 2-C-methyl erythritol (5), kaempferol-7-O-beta-glucopyranoside (6), kaempferol-3-O-beta-glucopyranoside (7) and quecetine-3-O-beta-glucopyranoside (8). The structure of new compounds 1 and 2 were elucidated by spectroscopic analysis, while known compounds were confirmed by direct comparison of their NMR data with those reported in literature. This is the first report of the presence of phenolic constituents in Evolvulus alsinoides. The isolated compounds 1-5 and 8 were screened for anti-stress activity in acute stress induced biochemical changes in adult male Sprague-Dawley rats. Stress exposure has resulted in significant increase of plasma glucose, adrenal gland weight, plasma creatine kinase (CK), and corticosterone levels. Compound 1 displayed most promising antistress effect by normalizing hyperglycemia, plasma corticosterone, CK and adrenal hypertrophy, while compounds 2 and 3 were also effective in normalizing most of these stress parameters, however compounds 4, 5 and 8 were ineffective in normalizing these parameters.     

Phenylpropanoid glycosides from Rhodiola rosea

Rhodiola rosea L. (Golden Root) has been used for a long time as an adaptogen in Chinese traditional medicine and is reported to have many pharmacological properties. Along its known secondary metabolites tyrosol (1), salidroside (rhodioloside) (2), rosin (3), rosarin (4), rosavin (5), sachaliside 1 (6) and 4-methoxy-cinnamyl-O-beta-D-glucopyranoside (7), four compounds were isolated from aqueous methanol extract of the plant and identified as cinnamyl-(6'-O-beta-xylopyranosyl)-O-beta-glucopyranoside (8), 4-methoxy-cinnamyl-(6'-O-alpha-arabinopyranosyl)-O-beta-glucopyranoside (9), picein (10) and benzyl-O-beta-glucopyranoside (11) by UV, MS and NMR methods. Compounds 8 and 9 are new natural compounds whereas compounds 10 and 11 were isolated first time from R. rosea. Also the compounds 6 and 7 are isolated earlier only from the callus cultures of the plant but not from the differentiated plant.     

New flavonoid glycosides from the leaves of Solidago altissima

Two new flavonoid glycosides kaempferol 3-O-beta-D-apiofuranosyl-(1-->6)-beta-D-glucopyranoside (1), and quercetin 3-O-beta-D-apiofuranosyl-(1-->6)-beta-D-glucopyranoside (2), together with six known flavonoid glycosides were isolated from the leaves of Solidago altissima L. grown in Kochi of Japan. The structure elucidation of the isolated compounds was performed by acid hydrolysis and spectroscopic methods including UV, IR, ESI-MS, 1D- and 2D-NMR experiments.     

Myeloperoxidase inhibitory and radical scavenging activities of flavones from Pterogyne nitens

Two new flavone glucosides, nitensosides A and B (1, 2), together with four known compounds, sorbifolin (3), sorbifolin 6-O-beta-glucopyranoside (4), pedalitin (5), and pedalitin 6-O-beta-glucopyranoside (6) were isolated from Pterogyne nitens. Their structures were elucidated from 1D and 2D NMR analysis, as well as by high resolution mass spectrometry. All the isolated flavones were evaluated for their myeloperoxidase (MPO) inhibitory activity. The most active compound, pedalitin, exhibited IC50 value of 3.75 nM on MPO. Additionally, the radical-scavenging capacity of flavones 1-6 was evaluated towards ABTS and DPPH radicals and compared to standard compounds quercetin and Trolox.     

New chemical constituents of roots of Urtica triangularis HAND-MASS

Studies on the chemical constituents of roots of Urtica triangularis HAND-MASS have led to the isolation of four new compounds. The structures, including the absolute configurations, of these constituents have been elucidated through spectral studies including (1)H-NMR, (13)C-NMR, 2D-NMR experiments (heteronuclear single-quantum coherence, heteronuclear multiple bonding connectivity and nuclear Overhauser effect spectroscopy), high resolution mass spectroscopy (HR-MS) and circular dichroism as (-)-4-methoxy-8'-acetyl olivil, (-)-4-methoxy-8'-acetyl olivil-4-O-alpha-arabinopyronosyl-(1-->6)-beta-glucopyranoside, (-)-olivil-9-O-beta-glucopyranoside and cyclo-olivil-9-O-beta-glucopyranoside.     

Medicinal foodstuffs. XXV. Hepatoprotective principle and structures of ionone glucoside, phenethyl glycoside, and flavonol oligoglycosides from young seedpods of garden peas, Pisum sativum L

A new ionone glucoside, pisumionoside, a phenethyl glycoside, sayaendoside, and two acylated flavonol oligoglycosides, pisumflavonosides I and II, were isolated from the young seedpods of garden peas, Pisum sativum L., together with quercetin and kaempferol 3-O-(6-O-trans-p-coumaroyl)-beta-D-glucopyranosyl (1-->2)-beta-D-glucopyranosyl (1-->2)-beta-D-glucopyranosides and quercetin and kaempferol 3-sophorotriosides. The structures of pisumionoside, sayaendoside, and pisumflavonosides I and II were determined on the basis of chemical and physicochemical evidence, respectively. Quercetin 3-sophorotrioside, a principle component, was found to show protective effects on liver injury induced by D-galactosamine and lipopolysaccharide and by carbon tetrachloride in mice.     

New iridoid glucosides from the aerial parts of Verbena brasiliensis

Two new iridoid glucosides, verbenabraside A (1) and verbenabraside B (2), were isolated from the aerial parts of Verbena brasiliensis VELL., along with six known iridoid glucosides, gelsemiol 3-O-beta-D-glucoside (3), verbraside (4), 9-hydroxysemperoside (5), griselinoside (6), aralidioside (7), and 6alpha-hydroxyforsythide dimethyl ester (8), three known phenylethanoid glycosides, 2-phenylethyl O-beta-D-xylopyranosyl-(1-->2)-beta-D-glucopyranoside (9), acteoside (10), and leucosceptoside A (11), two known lignan glucosides, dihydroxymethyl-bis(3,5-dimethoxy-4-hydroxyphenyl) tetrahydrofuran-9 (or 9')-O-beta-glucopyranoside (12) and (+)-lyoniresinol 3alpha-O-beta-D-glucopyranoside (13), a known methyl salicylate glucoside, methyl 2-O-beta-D-glucopyranosylbenzoate (14), and two known sterols, beta-sitosterol 3-O-beta-D-glucopyranoside (15) and beta-sitosterol (16). Their chemical structures were determined on the basis of spectroscopic data. Compound 1 exhibited stronger scavenging effect on the stable free radical 1,1-diphenyl-2-picrylhydrazyl than that of alpha-tocopherol.     

Study on the phenolic constituents of the flowers and leaves of Trifolium repens L

The flowers and leaves of Trifolium repens L. (Fabaceae) were subjected to phytochemical investigation in order to identify their major chemical constituents and to evaluate in?vitro antioxidant activity of the isolated compounds against DPPH˙. A total of 12 flavonoids, pterocarpan and methyl caffeate were isolated, then characterised by UV, MS, NMR spectroscopy and identified as quercetin and kaempferol 3-O-(6″-α-rhamnopyranosyl-2″-β-xylopyranosyl)-β-galactopyranosides (1, 2), kaempferol 3-O-(2″,6″-α-dirhamnopyranosyl)-β-galactopyranoside, mauritianin (3), quercetin and kaempferol 3-O-(2″-β-xylopyranosyl)-β-galactopyranosides (4, 5), kaempferol and quercetin 3-O-β-(6″-O-acetyl)-galactopyranosides (6, 7), trifolin (8), hyperoside (9), myricetin 3-O-β-galactopyranoside (10), quercetin (11), ononin (12), medicarpin 3-O-β-glucopyranoside (13) and methyl caffeate (14). Mauritianin, ononin, pterocarpan and methyl caffeate have been reported in this plant for the first time. The compounds 4, 7, 9, 10, and 11 were tested for their antioxidant effect against DPPH˙. All studied compounds were found to have potent activity, but the most effective in the test were compounds 9, 10 and 11 (EC(50) values in the range 7.51-9.52?μM).     

Lucidin type anthraquinone glycosides from Putoria calabrica

Two new lucidin type anthraquinone glycosides, putorinoside A (1) and putorinoside B (2) were isolated from Putoria calabrica, in addition to two known anthraquinone glycosides, lucidin 3-O-beta-glucopyranoside (3) and lucidin 3-O-primeveroside (4). Based on spectroscopic data, putorinosides A and B were identified as 2-hydroxymethyl-1-methoxy-3,5,6-trihydroxyanthraquinone 3-O-beta-glucopyranoside and 2-hydroxymethyl-1-methoxy-3,6-dihydroxyanthraquinone 3-O-beta-glucopyranoside, respectively.     

Five new bidesmoside triterpenoid saponins from Stauntonia chinensis

Eleven triterpenoid saponins (1-11) were isolated from Stauntonia chinensis DC. (Lardizabalaceae), including five new compounds, yemuoside YM(21-25) (1-3, 6, 7) structures of which were elucidated by chemical methods and a combination of MS, 1D- and 2D- NMR experiments including DEPT, (1)H--(1)H COSY, HSQC, HMBC, TOCSY, and NOESY as 3-O-alpha-L-arabinopyranosyl-(1 --> 3)-[alpha-L-rhamnopyranosyl-(1 --> 2)-]alpha-L-arabinopyranosyl-akebonicacid-28-O-alpha-L-rhamnopyranosyl-(1 --> 4)-beta-D-glucopyranosyl-(1 --> 6)-beta-D-glucopyranosyl ester (1), 3-O-beta-D-xylopyranosyl-(1 --> 3)-alpha-L-rhamnopyranosyl-(1 --> 2)-alpha-L-arabinopyranosyl-akebonic acid-28-O-alpha-L-rhamnopyranosyl-(1 --> 4)-beta-D-glucopyranosyl-(1 --> 6)-beta-D-glucopyranosyl ester (2), 3-O-beta-D-glucopyranosyl-(1 --> 3)-alpha-L-arabinopyranosyl-akebonic acid-28-O-alpha-L-rhamnopyranosyl-(1 --> 4)-beta-D-glucopyranosyl-(1 --> 6)-beta-D-glucopyranosyl ester (3), 3-O-alpha-L-arabinopyranosyl-(1 --> 3)-[alpha-L-rhamnopyranosyl-(1 --> 2)-]alpha-L-arabinopyranosyl-akebonic acid-28-O-beta-D-glucopyranosyl-(1 --> 6)-beta-D-glucopyranosyl ester (6), 3-O-alpha-L-arabinopyranosyl-(1 --> 3)-[alpha-L-arabinopyranosyl-(1 --> 2)-]alpha-L-arabinopyranosyl-akebonic acid-28-O-beta-D-glucopyranosyl-(1 --> 6)-beta-D-glucopyranosyl ester (7).     

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.     

Norlanostane and lanostane glycosides from the bulbs of Chionodoxa luciliae and their cytotoxic activity

Ten lanostane glycosides (1-10), including two new norlanostane glycosides (2 and 7) and a new lanostane glycoside with a spirolactone ring system (9), were isolated from the fresh bulbs of Chionodoxa luciliae (Liliaceae). The structures of the new compounds were determined on the basis of extensive spectroscopic analysis and the results of hydrolytic cleavage to be (23S)-3beta-[(O-beta-D-apiofuranosyl-(1-->2)-O-[beta-D-glucopyranosyl-(1-->3)]-O-beta-D-glucopyranosyl-(1-->2)-alpha-L-arabinopyranosyl-(1-->6)-beta-D-glucopyranosyl)oxy]-17alpha,23-epoxy-28,29-dihydroxy-27-norlanost-8-en-24-one (2), (23S)-17alpha,23-epoxy-29-hydroxy-3beta-[(O-alpha-L-rhamnopyranosyl-(1-->2)-O-[O-beta-D-glucopyranosyl-(1-->2)-beta-D-glucopyranosyl-(1-->3)]-O-beta-D-glucopyranosyl-(1-->2)-alpha-L-arabinopyranosyl-(1-->6)-beta-D-glucopyranosyl)oxy]-27-norlanost-8-ene-15,24-dione (7), and (23S,25R)-17alpha,23-epoxy-29-hydroxy-3beta-[(O-alpha-L-rhamnopyranosyl-(1-->2)-O-[beta-D-glucopyranosyl-(1-->3)]-O-beta-D-glucopyranosyl-(1-->2)-alpha-L-arabinopyranosyl-(1-->6)-beta-D-glucopyranosyl)oxy]lanost-8-en-23,26-olide (9), respectively. The cytotoxic activity of the isolated compounds against HSC-2 human oral squamous cell carcinoma cells are also reported.     

Megastigmane glucosides from Equisetum debile and E. diffusum

A new megastigmane diglucoside, (3S,5R,6S,7E,9S)-megastigman-7-ene-5,6-epoxy-3,9-diol 3,9-O-beta-D-diglucopyranoside (3), was isolated from the aerial portion of Equisetum debile along with macarangioside D (debiloside A), sammangaoside A, (6R,9S)-3-oxo-alpha-ionol 9-O-beta-D-glucopyranoside, debiloside B, kaempferol 3-O-sophoroside, kaempferol 3,7-O-beta-D-diglucopyranoside, kaempferol 3-O-sophoroside-7-O-beta-D-glucopyranoside, phenylethyl O-beta-D-glucopyranoside, (Z)-3-hexenyl O-beta-D-glucopyranoside, (7S,8R)-dehydrodiconiferyl 4-O-beta-D-glucopyranoside, and L-tryptophan. The absolute configuration at C-6 of the original structure of debilo-side A was revised to 6R-configuration, and was identical with macarangioside D (1). From the aerial portion of E. diffusum, four compounds, sammangaoside A, kaempferol 3-O-sophoroside and L-tryptophan and (3S,5R,6S,7E,9S)-megastigman-7-ene-5,6-epoxy-3,9-diol 3-O-beta-D-glucopyranoside were identified. The spectroscopic data of (3S,5R,6S,7E,9S)-megastigman-7-ene-5,6-epoxy-3,9-diol 3-O-beta-D-glucopyranoside (13) were found to be identical with corchoionoside A (9R-isomeric compound). The structure of corchoionoside A was also discussed. Structure determinations were based on physical data and spectroscopic evidence.