New flavane gallates isolated from the leaves of Plicosepalus curviflorus and their hypoglycemic activity

Two new flavane gallates were isolated from the leaves of Plicosepalus curviflorus. The structure of the new compounds was established as 2S,3R-3,3′,4′,5,7-pentahydroxyflavane-5-O-gallate (1) and 2S,3R-3,3′,4′,5,5′,7-hexahydroxyflavane-4′,5-di-O-gallate (2), respectively. In addition, seven known compounds (−)-catechin (3), quercetin (4), lupeol (5), β-sitosterol (6), pomolic acid (7), β-sitosterol 3-O-β-d-glucopyranoside (8) and 4-methoxycinnamic acid (9) were reported for the first time from the genus Plicosepalus. Compounds 1, 2 and 3 were investigated for their hypoglycemic activity and showed significant hypoglycemic activity in Swiss Albino mice.     

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.     

Sesquiterpenes inhibiting NO production from Celastrus orbiculatus

Two new (1 and 2) and one known (3) β-dihydroagarofuran sesquiterpenes were isolated from the fruits of Celastrus orbicultus Thunb. Their structures were elucidated as 1β,13-diacetoxy-8β,9β-dibenzoyloxy-β-dihydroagarofuran (1), 1β,13-diacetoxy-8α-hydroxy-9β-benzoyloxy-β-dihydroagarofuran (2), and 1β,6α,13-triacetoxy-9α-benzoyloxy-β-dihydroagarofuran (3), on the basis of spectroscopic data analyses. All the compounds exhibited inhibitory effects on LPS-induced nitric oxide production in murine microglial BV-2 cells.     

Dammarane-type glycosides and long chain sesquiterpene glycosides from Gynostemma yixingense

A new dammarane-type glycoside and a new long chain sesquiterpene glycoside, along with nine known compounds 20(S)-ginsenoside Rh1 (3), 20(R)-ginsenoside Rh1 (4), ginsenoside F1 (5), amarantholidoside IV (6), ginsenoside Rc (7), 20(S)-ginsenoside Rg2 (8), 20(R)-ginsenoside Rg2 (9), ginsenoside Rd (10) and gypenoside XLVI (11) were isolated from Gynostemma yixingense. The structures of the new compounds were determined on the basis of spectroscopic analysis, including 1D-, 2D-NMR and ESI-MS techniques as well as by comparison of the spectral data with those of related compounds as 2α,3β,20(S)-trihydroxydammar-24-ene-3-O-[β-d-glucopyranosyl((1 → 2)-β-d-glucopyranosyl]-20-O-[β-d-xylopyranosyl((1 → 6)-β-d-glucopyranoside] (1) (2E,6E)-10-β-d-glucopyranosyl-1,10,11-trihydroxy-3,7,11-trimethyldodeca-2,6-diene (2).     

Three new sesquiterpenes from Tithonia diversifolia and their anti-hyperglycemic activity

Three new germacrane sesquiterpenes (1), (2), (3), along with eleven known sesquiterpenes, namely, tirotundin-3-O-methyl ether (4), deacetylvguiestin (5), 1β-hydroxydiversifolin-3-O-methyl ether (6), tagitinin C (7), 1β-hydroxytirotundin-3-O-methyl ether (8), 1β-hydroxytirotundin-1,3-O-dimethyl ether (9), tagitinin F-3-O-methyl ether (10), tagitinin F (11), tagitinin A (12), 3β-acetoxy-4α-hydroxyeduesm-11(13)-en-12-oic acid (13) and ilicic acid (14) were isolated from the aerial parts of Tithonia diversifolia. Their structures were established by spectroscopic analysis, while the relative configuration of compound 1 was confirmed by X-ray diffraction analysis. In addition, compounds 1–14 were evaluated in vitro for their anti-hyperglycemic activity by glucose uptake in 3T3-L1 adipocytes. It was found that 10 μg/mL 1, 3, 6 and 8 could significantly increase glucose uptake without significant toxic effects.     

New triterpene saponins from the root of Ilex pubescens

Two new triterpene glycosides named ilexpublesnin A (1) and ilexpublesnin B (2) were isolated from the root of Ilex pubescens. Their structures were determined as 3-O-(β-d-xylopyranosyl)-28-O-(β-d-glucopyranosyl)-3β, 19α-dihydroxyurs-23-oxo-12-en-28-oic acid (1) and 28-O-(β-d-xylopyranosyl-(2 → 1)-β-d-glucopyranosyl)-3β, 19α-dihydroxyurs-23-oxo-12-en-28-oic acid (2) on the basis of chemical and spectroscopic methods.     

Flavonoid glycosides from Microtea debilis and their cytotoxic and anti-inflammatory effects

Two new 5-O-glucosylflavones, 5-O-β-d-glucopyranosyl cirsimaritin (1) and 5, 4′-O-β-d-diglucopyranosyl cirsimaritin (2), four known flavonoids, cirsimarin (3), cirsimaritin (4), salvigenin (5), 4′, 5-dihydroxy-7-methoxyflavone (6), and a norisoprenoid, vomifoliol (7), have been isolated from the aerial parts of Microtea debilis. All isolates were tested for cytotoxicity in human cancer cell lines (Hep G2, COLO 205, and HL-60) and anti-inflammatory activities in LPS-treated RAW264.7 macrophages. Compound 6 was found to be a potent inhibitor to nitrite production in macrophages. Compounds 2, 4, 6, and 7 showed moderate anti-proliferative activity against COLO-205 cells with IC₅₀ values of 7.1, 13.1, 6.1, and 6.8 μM, respectively.     

New anthraquinone glycosides from the roots of Morinda citrifolia

Six new anthraquinone glycosides: digiferruginol-1-methylether-11-O-β-gentiobioside (1); digiferruginol-11-O-β-primeveroside (2); damnacanthol-11-O-β-primeveroside (3); 1-methoxy-2-primeverosyloxymethyl-anthraquinone-3-olate (4); 1-hydroxy-2-primeverosyloxymethyl-anthraquinone-3-olate (5); and 1-hydroxy-5,6-dimethoxy-2-methyl-7-primeverosyloxyanthraquinone (6) were isolated from Morinda citrifolia (Rubiaceae) roots together with four known anthraquinone glycosides. The structures of the new compounds were established using spectral methods. For five of the new compounds, the sugar is attached via the hydroxymethyl group of the anthraquinone C-2 carbon. This type of bond is rarely found for anthraquinone glycosides isolated from natural sources.     

A new 9-nor-atractylodin from Atractylodes lancea and the antibacterial activity of the atractylodin derivatives

A new compound, namely, 9-nor-atractylodin (1) and one known atractylodin (2) were isolated from the rhizomes of Atractylodes lancea. The structural modifications of atractylodin were carried out and a series of atractylodin derivatives (3-10) were obtained. The antibacterial activities of 1-10 were examined against Escherichia coli, Staphylococcus aureus, Bacillus subtilis and Candida albicans. Compounds 4 and 8, which contained the α, β-unsaturated carbonyl fragment, were found to be active against E. coli and S. aureus.     

Mushroom tyrosinase inhibitors from Aloe barbadensis Miller

Two new chromones, 5-((S)-2′-oxo-4′-hydroxypentyl)-2-(β-glucopyranosyl-oxy-methyl)chromone (1) and 5-((S)-2′-oxo-4′-hydroxypentyl)-2-methoxychromone (2), together with four known analogues, 8-C-glucosyl-7-O-methyl-(S)-aloesol (3), isoaloeresin D (4), 8-C-glucosyl-(R)-aloesol (5), and aloesin (6) were isolated from the aqueous extract of Aloe barbadensis Miller. Their structures were determined on the basis of spectroscopic evidences (1-D and 2-D NMR, HRMS, UV, and IR data), chemical methods and the literature data. The Mosher's method was applied to establish the absolute configuration of compounds 1 and 2. The inhibitory effects of these chromones on the activity of mushroom tyrosinase were examined, and compound 6 was identified as a noncompetitive tyrosinase inhibitor with an IC₅₀ value of 108.62 μg·mL^− 1.     

Trichalasins C and D from the plant endophytic fungus Trichoderma gamsii

Two new cytochalasans, trichalasins C (1) and D (2) together with known cytochalasans aspochalasins D (3), M (4) and P (5) were isolated from one endophytic fungus Trichoderma gamsii inhabiting in traditional medicinal plant Panax notoginseng (BurK.) F.H.Chen. The structures for the new compounds 1 and 2 were determined by NMR and HRESIMS, and their relative configurations were established by analysis of coupling constants and NOESY correlations. Compound 3 displaying inhibitory activity with EC₅₀ value 5.72 μM, whereas the EC₅₀ values for compounds 1, 2 and 4, 5 are more than 40 μM.     

Triterpenes and steroids from the roots of Scorzonera austriaca

A new D:B-friedoolean-type triterpene, 3β-acetoxyglutin-5(10)-en-6-oxo (1), together with seventeen known compounds (2-18) was isolated from the roots of Scorzonera austriaca. Their structures were elucidated mainly by NMR and HR-ESI-MS, as well as on comparison with the reported data. Cytotoxicities of compounds 2, 4, 6, 10-14 and 16 against selected cancer cells of human promyelocytic leukemia (HL-60) and human hepatoma (BEL-7404) were measured in vitro.     

New withanolides from Mandragora officinarum: First report of withanolides from the Genus Mandragora

Two new withanolides named mandragorolide A (1) and mandragorolide B (2) were isolated from the MeOH extract of the whole plant of Mandragora officinarum of Jordanian origin, along with five known withanolides namely larnaxolide A (3), withanolide B (4), datura lactone 2 (5), withanicandrin (6) and salpichrolide C (7). Compound 3 has been reported only once before, from the leaves of Larnax glabra. This is the first report of withanolides of different biogenetic types from the genus Mandragora. Isolation of known fatty compounds, coumarins, sterols and tropane alkaloids was also achieved in this study.     

New diterpenoids and cytotoxic and anti-inflammatory diterpenoids from Amentotaxus formosana

Two new abietane diterpenoids, ramentoxide (1) and ramentoxidone (2) and a new icetexane diterpenoid, amentonone (3) were isolated from the barks of Amentotaxus formosana. The structures of 1-3 were determined by spectroscopic methods. Known compounds brevitaxin (4), and (+)-ferruginol (5) and ent-kaur-16-en-15-one (6) isolated from this plant revealed potent cytotoxic activity against human breast adenocarcinoma cells, MCF-7 cells with an IC₅₀ value of 0.08 ± 0.05 μg/mL, and significant anti-inflammatory activities, respectively.     

Sesquiterpenes and acetogenins from the marine red alga Laurencia okamurai

Three new halogenated sesquiterpenes, 10-bromo-7α,8α-expoxychamigr-1-en-3-ol (1), 10-bromo-β-chamigren-8-ol (2), and 10-bromo-3-chlorocupar-5-en-2-ol (3), one new C₁₂-acetogenin, desepilaurallene (7), one new naturally occurring sesquiterpene, 7-hydroxylaurene acetate (4), two known sesquiterpenes, allolaurinterol acetate (5) and laurene (6), and one known C₁₅-acetogenin, epilaurallene (8), were isolated from the marine red alga Laurencia okamurai collected from the coast of Rongcheng, China. The structures of these compounds were unambiguously established by 1D, 2D NMR and mass spectroscopic techniques. The bioassay results showed that 4, 5 exhibited potent antibacterial activity, and 1, 4, 5 were toxic to brine shrimp.     

Two new benzophenone glycosides from the fruit of Psidium guajava L.

The ripe edible fruits of Psidium guajava L. was phytochemically investigated, three benzophenone glycosides, 2, 6-dihydroxy-3, 5-dimethyl-4-O-β-D-glucopyranosyl-benzophenone (1), 2, 6-dihydroxy-3-methyl-4-O-(6″-O-galloyl-β-D-glucopyranosyl)-benzophenone (2), 2, 6-dihydroxy-3, 5-dimethyl-4-O-(6″-O-galloyl-β-D-glucopyranosyl)-benzophenone (3) were isolated by means of chromatography, and their structures were elucidated on the basis of mass spectrometry, ¹H NMR, ¹³C NMR, HSQC and HMBC data. Compounds 1 and 2 were new benzophenone glycosides, and here we report the complete spectroscopic assignments for 3.     

New spirobenzofuranoid dibenzocyclooctadiene lignans from Kadsura oblongifolia

Two new spirobenzofuranoid dibenzocyclooctadiene lignans, kadsulignans O (1) and P (2) were isolated from the stems of Kadsura oblongifolia, together with five known same type lignans, kadsulignans C (3), E (4), F (5), G (6), and heteroclitin J (7). Their structures were elucidated on the basis of spectral evidences and comparisons with literatures. Compounds 3-7 were isolated from this plant for the first time.     

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 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.