Polyoxypregnane glycosides from the flowers of Dregea volubilis

Three novel polyoxypregnane glycosides, volubiloside A, B and C (1-3), were isolated from the flowers of Dregea volubilis Linn., and their structures were elucidated as drevogenin D-3-O-beta-D-glucopyranosyl (1-->4)-6-deoxy-3-O-methyl-beta-D-allopyranosyl (1-->4)-beta-D-cymaropyranosyl (1-->4)-beta-D-cymaropyranoside, drevogenin D-3-O-beta-D-glucopyranosyl (1-->4)-6-deoxy-3-O-methyl-beta-D-allopyranosyl (1-->4)-beta-D-cymaropyranosyl (1-->4)-beta-D-digitoxopyranoside and drevogenin P-3-O-beta-D-glucopyranosyl (1-->4)-6-deoxy-3-O-methyl-beta-D-allopyranosyl (1-->4)-beta-D-cymaropyranosyl (1-->4)-beta-D-cymaropyranoside, respectively, on the basis of extensive NMR experiments, MALDI-TOF MS, and some chemical strategies.     

Neolignan and flavonoid glycosides in Juniperus communis var. depressa

Two neolignan glycosides (junipercomnosides A and B) were isolated from aerial parts of Juniperus communis var. depressa along with two known neolignan glycosides and seven flavonoid glycosides. The structures of the isolated compounds were determined by spectral analysis, in particular by 2D-NMR analysis. The significance of distribution of flavonoids in the chemotaxonomy of genus Juniperus was also discussed.     

Iridoid glycosides from Harpagophytum procumbens D.C. (devil's claw)

Iridoid glycosides, harprocumbide A (6'-O-alpha-D-galactopyranosylharpagoside, 1) and harprocumbide B (6'-O-(cis-p-coumaroyl)-procumbide, 2) were isolated from the tubers of Harpagophytum prucumbens D.C., along with nine known iridoid glycosides 6-O-alpha-D-galactopyranosylharpagoside (3), and harpagoside (4), harpagide (5), 8-cinnamoylmyoporoside (6), 8-O-feruloylhapagide (7), procumbide (8), 6'-O-(p-coumaroyl)-procumbide (9), 8-O-(p-coumaroyl)-harpagide (10) and 8-O-(cis-p-coumaroyl)-harpagide (11). Compound 10 showed marginal inhibition activity against macrophages respiratory burst.     

Iridoid glycosides and cucurbitacin glycoside from Neopicrorhiza scrophulariiflora

Three iridoid glycosides, picrorosides A (1), B (2) and C (3), and a cucurbitacin glycoside, scrophoside A (4), were isolated from the rhizomes of Neopicrorhiza scrophulariiflora (Scrophulariaceae), along with two known iridoid glycosides, picrosides I (5) and II (6), and three known cucurbitacin glycosides (7-9). Their structures were elucidated on the basis of both chemical and spectroscopic data.     

Two chromone-secoiridoid glycosides and three indole alkaloid glycosides from Neonauclea sessilifolia

From the dried roots of Neonauclea sessilifolia, two new chromone-secoiridoid glycosides, sessilifoside and 7"-O-beta-D-glucopyranosylsessilifoside, and three novel indole alkaloid glycosides, neonaucleosides A, B, and C, were isolated along with the main known glycosides, 5-hydroxy-2-methylchromone-7-O-beta-D-apiofuranosyl-(1-->6)-beta-D-glucopyranoside, sweroside, loganin, grandifloroside, and quinovic acid 3 beta-O-beta-D-quinovopyranoside-28-O-beta-D-glucopyranoside. The structures of these new glycosides were determined by spectroscopic and chemical means. Neonaucleoside A and its C-3 epimer were prepared from secologanin and tryptamine.     

通光藤甙F,G,H和I结构

从通光藤(Marsdeniatenacissima)的茎中分离得到4个新的C21甾体甙———通光藤甙F(3),G(4),H(5)和I(6),以及2个已知化合物通光藤甙A(1)和B(2)。根据光谱数据和化学方法推定了其结构。同时,通过COLOC谱和二维核磁共振谱指定了这些化合物中甙元上11和12位的酯基确切连接位置。     

Melanogenesis inhibitory activity of monoterpene glycosides from gardeniae fructus

A new iridoid glycoside, 10-O-(4″-O-methylsuccinoyl)geniposide (7), and two new pyronane glycosides, jasminosides Q and R (13 and 14, resp.), along with nine known iridoid glycosides, 1-6 and 8-10, and two known pyronane glycosides, 11 and 12, were isolated from a MeOH extract of Gardeniae Fructus, the dried ripe fruit of Gardenia jasminoides (Rubiaceae). The structures of new compounds were elucidated on the basis of extensive spectroscopic analyses and comparison with literature. Upon evaluation of compounds 1-14 on the melanogenesis in B16 melanoma cells induced with α-melanocyte-stimulating hormone (α-MSH), three compounds, i.e., 6-O-p-coumaroylgeniposide (3), 7, and 6'-O-sinapoyljasminoside (12), exhibited inhibitory effects with 21.6-41.0 and 37.5-47.7% reduction of melanin content at 30 and 50?μM, respectively, with almost no toxicity to the cells (83.7-106.1% of cell viability at 50?μM).     

Phenolic glycosides from Barnettia kerrii

From the leaves and branches Barnettia kerrii, two verbascoside derivatives (6"-O-acetylverbascoside and 4"'-O-acetylverbascoside), as well as two phenolic glycosides (khaephuosides A and B) were isolated together with 15 known compounds. The structural elucidations were based on analyses of spectroscopic data.     

nor-Oleanene type triterpene glycosides from the leaves of Acanthopanax japonicus

Three new (1-3) and two known (4-5) triterpene glycosides were isolated from the leaves of Acanthopanax japonicus (Araliaceae) and elucidated structurally by mass, 1D, and 2D NMR spectroscopy. All the compounds possessed a nor-oleanene triterpene skeleton as the aglycone. The structures of 1-5 were established as 28-O-alpha-L-rhamno-pyranosyl-(1-->4)-beta-D-glucopyranosyl-(1-->6)-beta-D-glucopyranosyl ester of 3beta-hydroxy- 30-nor-olean-12,20(29)-diene-23,28-dioic acid, designated as acanjaposide A, 3beta- hydroxy-23-oxo-30-nor-olean-12,20(29)-diene-28-oic acid, named acanjaposide B, 3beta,20alpha-dihydroxy-23-oxo-30-nor-olean-12-en-28-oic acid, named acanjaposide C, and nipponoside E, a known saponin, respectively.     

Cucurbitacins from Bacopa monnieri

Four cucurbitacins, bacobitacin A-D (1-4) as well as, a known cytotoxic, cucurbitacin E (5) together with three known phenylethanoid glycosides, monnieraside I, III and plantioside B were isolated form the aerial part of Bacopa monnieri. Their structures were elucidated on the basis of extensive spectroscopic investigations (1D, 2D NMR and ESI-QTOF-MS/MS). This is the first report on the characterization of cucurbitacins in B. monnieri.     

Phenylethanoids, iridoids and a spirostanol saponin from Veronica turrilliana

From the aerial parts of Veronica turrilliana two phenylethanoid glycosides, turrilliosides A and B and a steroidal saponin, turrillianoside were isolated and their structures elucidated as beta-(3,4-dihydroxyphenyl)ethyl-4-O-E-caffeoyl-O-[beta-glucopyranosyl-(1-->4)-alpha-rhamnopyranosyl-(1-->6)]-beta-glucopyranoside, beta-(3,4-dihydroxyphenyl)ethyl-4-O-E-caffeoyl-[6-O-E-feruloyl-beta-glucopyranosyl-(1-->4)-alpha-rhamnopyranosyl-(1-->6)]-beta-glucopyranoside and (23S,25S)-12beta,23-dihydroxyspirost-5-en-3beta-yl O-alpha-rhamnopyranosyl-(1-->4)-beta-glucopyranoside, respectively. Furthermore, eight known glucosides are reported namely, catalpol, catalposide, verproside, amphicoside, isovanilloylcatalpol, aucubin, arbutin, and 6-O-E-caffeoylarbutin, the latter two for the first time in the genus Veronica. The two phenylethanoid glycosides were found to be potent DPPH radical scavengers. All of the tested compounds were inactive against the representative species of fungi and bacteria.     

Steroidal glycosides from the roots of Cynanchum amplexicaule Sieb. et Zucc

Seven new steroidal glycosides (amplexicosides A (4), B (7), C (8), D (9), E (10), F (11), and G (12)), along with six known compounds (cynatratoside A (1), tylophoside A (2), cynatratoside B (3), glaucogenin A (5), glaucoside A (6), and hancoside A (13)) were isolated from the 95% ethanol extract of the roots of Cynanchum amplexicaule (Sieb. et Zucc.). Their structures were determined based on spectral and chemical evidence. Compound 12 has a 14, 15-secopregnane-type skeleton aglycone, which has not been reported in literature.     

Sesquiterpene lactone glucosides and alkyl glycosides from the fruit of cumin

From the polar portion of the methanolic extract of cumin (fruit of Cuminum cyminum L.), two sesquiterpenoid glucosides, cuminoside A and B, and two alkyl glycosides were isolated together with five known compounds. Their structures were established as (1S,5S,6S,10S)-10-hydroxyguaia-3,7(11)-dien-12,6-olide beta-D-glucopyranoside, (1R,5R,6S,7S,9S,10R,11R)-1,9-dihydroxyeudesm-3-en-12,6-olide 9-O-beta-D-glucopyranoside, methyl beta-D-apiofuranosyl-(1-->6)-beta-D-glucopyranoside and ethane-1,2-diol 1-O-beta-D-apiofuranosyl-(1-->6)-beta-D-glucopyranoside, respectively.     

4'-deoxy iridoid glycosides from Centranthus longiflorus

The new iridoid glycosides, 4'-deoxykanokoside A and 4'-deoxykanokoside C, were isolated from the methanolic root extract of Centranthus longiflorus ssp. longiflorus. They were accompanied by the three known iridoid glycosides, kanokoside A, kanokoside C and valerosidatum, and two known phenylpropanoid glycosides, coniferin and isoconiferinoside. The structures were elucidated mainly by spectroscopic methods. The presence of 4-deoxy glucose as a part of plant glycosides is rather unusual. Cytotoxic effects of the isolated compounds were also investigated.     

Steroidal glycosides from Cynanchum forrestii Schlechter

Nine new steroidal glycosides, cynaforrosides B, C, D, E, and F, based on a 13, 14: 14, 15-disecopregnane-type skeleton, cynaforrosides G, H, and I with a new aglycone named cynaforrogenin A, and cynaforroside J together with three known C21 steroidal glycosides cynatratoside A, hancoside and komaroside C were isolated from the ethanol extract of the roots of Cynanchum forrestii Schlechter. The structures of new compounds were determined on the basis of spectral and chemical evidence. Steroidal glycosides with three kinds of skeletons were isolated from this plant simultaneously. The sugar units of cynaforrosides B-I contained two moieties of glucoses and especially cynaforrosides E-I contained two glucoses with the mode of 1-->6 linkage, which were rare among steroidal glycosides of the genus Cynanchum.     

Chemotaxonomic markers in Digitalideae (Plantaginaceae)

In a chemosystematic investigation of Digitalideae (Plantaginaceae), the water-soluble part of extracts of two species of Digitalis, two species of Isoplexis, as well as Erinus alpinus and Lafuentea rotundifolia were studied with regard to their content of main carbohydrates, iridoids and caffeoyl phenylethanoid glycosides (CPGs). Digitalis and Isoplexis contained sorbitol, cornoside and a number of other phenylethanoid glycosides including the new tyrosol beta-D-mannopyranoside, sceptroside but were found to lack iridoid glucosides. Erinus contained mainly glucose, the new 8,9-double bond iridoid, erinoside, and a number of known iridoid glucosides including two esters of 6-rhamnopyranosylcatalpol, as well as the CPG poliumoside. Finally, Lafuentea was characterized by the presence of glucose, aucubin and cryptamygin B but apparently lacked CPGs. The chemosystematic significance of the isolated compounds is discussed.     

Phenylethanoid Glycosides from Caryopteris aureoglandulosa and Their Biological Activities

This study describes the isolation and identification of two novel phenylethanoid glycosides, aureoglanduloside A ( 1 ) and aureoglanduloside B ( 2 ), as well as a newly discovered diterpene glycoside, aureoglanduloside C ( 29 ). Additionally, 31 known compounds were isolated from the n-butyl alcohol (BuOH) soluble fraction of Caryopteris aureoglandulosa whole dried plants. Their structures were characterized using various spectroscopic techniques and high-resolution electrospray ionization mass spectroscopy (HR-ESI-MS). Furthermore, the neuroprotective effects of all phenylethanoid glycosides were evaluated. Specifically, compounds 2 and 10 – 12 exhibited the ability to promote the phagocytosis of myelin by microglia, and compounds 2 , 10 – 11 , and 24 showed the ability to promote the phagocytosis of myelin by astrocytes.     

Leishmanicidal cycloartane-type triterpene glycosides from Astragalus oleifolius

Two new cycloartane-type glycosides oleifoliosides A (1) and B (2) were isolated from the lower stem parts of Astragalus oleifolius. Their structures were identified as 3-O-[beta-xylopyranosyl-(1 --> 2)-alpha-arabinopyranosyl]-6-O-beta-xylopyranosyl-3beta,6alpha,16beta,24(S),25-pentahydroxycycloartane and 3-O-[beta-xylopyranosyl-(1 --> 2)-alpha-arabinopyranosyl]-6-O-beta-glucopyranosyl-3beta,6alpha,16beta,24(S),25-pentahydroxycycloartane, respectively, by means of spectroscopic methods (IR, 1D and 2D NMR, ESI-MS). Three known cycloartane glycosides cyclocanthoside E (3), astragaloside II (4) and astragaloside IV (5) were also isolated and characterized. All five compounds were evaluated for in vitro trypanocidal, leishmanicidal and antiplasmodial activities as well as their cytotoxic potential on primary mammalian (L6) cells. Except for the compound 5, all compounds showed notable growth inhibitory activity against Leishmania donovani with IC50 values ranging from 13.2 to 21.3 microg/ml. Only weak activity against Trypanosoma brucei rhodesiense was observed with the known compounds astragaloside II (4, IC50 66.6 microg/ml) and cyclocanthoside E (3, IC50 85.2 microg/ml), while all compounds were inactive against Trypanosoma cruzi and Plasmodium falciparum. None of the compounds were toxic to mammalian cells (IC50's > 90 microg/ml). This is the first report of leishmanicidal and trypanocidal activity of cycloartane-type triterpene glycosides.     

Polyoxypregnane glycosides from Caralluma retrospiciens

Six related polyoxypregnane glycosides were isolated and characterised from Caralluma retrospiciens leaves. The compounds were identified as 12beta-benzoyloxy-8beta,14beta-dihydroxypregn-20-one-3-O-[3-O-methyl-6-deoxy-beta-D-allopyranosyl-(1 --> 4)-beta-D-cymaropyranosyl-(1 --> 4)-]-beta-D-cymaropyranoside], 12beta-benzoyloxy-8beta,14beta-dihydroxypregn-20-one-3-O-[beta-D-glucopyranosyl-(1 --> 4)-3-O-methyl-6-deoxy-beta-D-allopyranosyl-(1 --> 4)-beta-D-cymaropyranosyl-(1 --> 4)-beta-D-cymaropyranoside], 12beta-benzoyloxy-8beta,14beta-dihydroxypregn-20-one-3-O-[beta-D-glucopyranosyl-(1 --> 4)-3-O-methyl-6-deoxy-beta-D-galactopyranosyl-(1 --> 4)-3-O-methyl-6-deoxy-beta-D-galactopyranoside], 12beta-benzoyloxy-8beta,14beta-dihydroxypregn-20-one-3-O-[beta-D-glucopyranosyl-(1 --> 6)-beta-D-glucopyranosyl-(1 --> 4)-3-O-methyl-6-deoxy-beta-D-galactopyranosyl-(1 --> 4)-3-O-methyl-6-deoxy-beta-D-galactopyranoside], 12beta-benzoyloxy-11alpha-isovaleroyloxy-8beta,14beta-dihydroxypregn-20-one-3-O-[beta-D-glucopyranosyl-(1 --> 4)-3-O-methyl-6-deoxy-beta-D-galactopyranosyl-(1 --> 4)-3-O-methyl-6-deoxy-beta-D-galactopyranoside], and 12beta-benzoyloxy-11alpha-isovaleroyloxy-8beta,14beta-dihydroxypregn-20-one-3-O-[beta-D-glucopyranosyl (1 --> 4)-3-O-methyl-6-deoxy-beta-D-allopyranosyl-(1 --> 4)-beta-D-cymaropyranosyl-(1 --> 4)-beta-D-cymaropyranoside]. The structures were determined by detailed analysis of one- and two-dimensional NMR spectra as well as by chemical means. The compounds showed cytotoxic activities towards brine shrimp having IC50 values of 1.19 x 10(-4), 8.83 x 10(-5), 2.64 x 10(-4), 2.26 x 10(-4), 2.39 x 10(-4) and 1.70 x 10(-4) M, respectively. This is the first report of the isolation of these compounds from a natural source.     

Newbouldiosides A-C, phenylethanoid glycosides from the stem bark of Newbouldia laevis

From the stem bark of Newbouldia laevis three phenylethanoid glycosides, designated as newbouldioside A-C, were isolated together with a sodium salt of analogue B and the known compounds, verbascoside, 5-hydroxydehydro-iso-alpha-lapachone, 3,8-dihydroxydehydro-iso-alpha-lapachone, apigenin and luteolin. The structures of the phenylethanoid glycosides were elucidated by spectroscopic methods as beta-(3,4-dihydroxyphenyl)ethyl 5-O-syringoyl-beta-D-apiofuranosyloxy-(1-->2)-O-[alpha-L-rhamnopyranosyl-(1-->3)]-beta-D-glucopyranoside, ss-(3,4-dihydroxyphenyl)ethyl 5-O-syringoyl-beta-D-apiofuranosyloxy-(1-->2)-O-[alpha-L-rhamnopyranosyl-(1-->3)]-6-O-E-feruloyl-beta-D-glucopyranoside, and beta-(3,4-dihydroxyphenyl)ethyl 3-O-E-feruloyl-beta-D-apiofuranosyloxy-(1-->2)-O-alpha-L-rhamnopyranosyl-(1-->2)-6-O-E-sinapoyl-beta-D-glucopyranoside, respectively.