New flavonol glycosides from Aconitum burnatii Gáyer and Aconitum variegatum L.

Six flavonol glycosides, compounds 1-3 from A. burnatii Gáyer and 4-6 from A. variegatum L., were obtained from their methanol extracts of aerial parts. The identified structures were quercetin 3-O-β-d-glucopyranoside-7-O-(6-E-p-coumaroyl)-β-d-glucopyranosyl-(1 → 3)-α-l-rhamnopyranoside (1), quercetin 3-O-β-d-glucopyranoside-7-O-β-d-glucopyranosyl-(1 → 3)-α-l-rhamnopyranoside (2), quercetin 3-O-β-d-glucopyranoside-7-O-(6-E-caffeoyl)-β-d-glucopyranosyl-(1 → 3)-α-l-rhamnopyranoside (3), kaempferol 3-O-β-d-galactopyranoside-7-O-α-l-arabinopyranoside (4), quercetin 3-O-β-d-glucopyranoside (5), and kaempferol 3-O-β-d-glucopyranoside (6). Compounds 1, 2 and 4 were isolated for the first time. The antioxidant potential of the methanol extracts and pure compounds was tested with different assays.     

Study on secondary metabolite content of Helleborus niger L. leaves

Phytochemical investigation of Helleborus niger L. (Ranunculaceae) leaf methanol extract allowed to isolate a phenolic glucoside derivative and two flavonoid glycosides characterized as phenyllactic acid 2-O-β-d-glucopyranoside (1), quercetin 3-O-2-(E-caffeoyl)-α-l-arabinopyranosyl-(1 → 2)-β-d-glucopyranoside-7-O-β-d-glucopyranoside (2), and kaempferol 3-O-α-l-arabinopyranosyl-(1 → 2)-β-d-galactopyranoside-7-O-β-d-glucopyranoside (3), respectively. Compounds 1 and 2 were isolated for the first time and their structural characterization was obtained on the basis of extensive NMR spectral studies.     

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.     

Polyprenylated isoflavanone and isoflavonoids from Ormosia henryi and their cytotoxicity and anti-oxidation activity

A rare naturally-occurring polyprenylated isoflavanone, designated ormosinol (1), and a new isoflavonoid glycoside, named ormosinoside (2), along with 21 known compounds were isolated from the root bark of Ormosia henryi Prain. The structures of compounds 1 and 2 were determined as 5,7,2′,4′-tetrahydroxyl-6,8,5′-tri-(γ,γ-dimethylallyl)isoflavanone and isoprunetin-7-O-β-d-xylopyranosyl-(1 → 6)-β-d-glucopyranoside on the basis of a combination of 1D-, 2D-NMR and mass spectroscopic measurements. Compound 1 showed significant anti-oxidation activity against DPPH radicals (IC₅₀ 28.5 μM) and cancer cell line (A549, LAC, and HepG2) growth inhibitory activity with IC₅₀ ranging from 4.25 to 7.09 μM, while compound 2 found to be inactive to both testing systems.     

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).     

Aporphine alkaloids,clerodane diterpenes,and other constituents from Tinospora cordifolia

Phytochemical investigation of the methanol extract of Tinospora cordifolia aerial parts led to the isolation of four new and seven known compounds. The structures of two new aporphine alkaloids, N-formylasimilobine 2-O-β-d-glucopyranosyl-(1 → 2)-β-d-glucopyranoside (tinoscorside A, 1) and N-acetylasimilobine 2-O-β-d-glucopyranosyl-(1 → 2)-β-d-glucopyranoside (tinoscorside B, 2), a new clerodane diterpene, tinoscorside C (3), and a new phenylpropanoid, sinapyl 4-O-β-d-apiofuranosyl-(1 → 6)-O-β-d-glucopyranoside (tinoscorside D, 6) were determined by extensive spectroscopic methods including FTICR-MS and 1D and 2D NMR.     

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.     

BACE inhibitory flavanones from Balanophora involucrata Hook. f.

One new flavanone (S)-5,7,3′,5′-tetrahydroxy-flavanone-7-O-(6″-galloyl)-β-D-glucopyranose (1), together with one known flavanone and four known dihydrochalcones were isolated from the ethyl acetate partitions from an alcoholic extract of the whole plant of Balanophora involucrata Hook. f. All of the compounds were characterized by spectroscopic methods. Their in vitro BACE inhibitory effects were evaluated. Compounds 1, 2, 4, and 5 were found to be a little more active than the positive control, although all of which are below 50% inhibition at 10 μM.     

Phenolic glycosides from Dodecadenia grandiflora and their glucose-6-phosphatase inhibitory activity

Phytochemical investigation of Dodecadenia grandiflora leaves led to the isolation and identification of three phenolic glycosides, designated 1-[(4′-O-(E)-p-coumaroyl)-β-d-glucopyranosyl]-oxy-2-phenol (1), 1-[(6′-O-(E)-p-coumaroyl)-β-d-glucopyranosyl]-oxy-2-phenol (2) and 1-[O-β-d-glucopyranosyl(1→2)-β-d-glucopyranosyl]-oxy-2-phenol (3), along with nine known compounds. Compounds 1, 2, 5 and 9 exhibited significant glucose-6-phosphatase inhibitory activity (63.7, 66.9, 82.9 and 85.4%) with IC₅₀ values of 88.5, 81.0, 51 and 50 μM respectively. On the basis of biological results, a structure–activity relationship has been discussed.     

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 antioxidant and antiglycation active triterpenoid saponins from the root bark of Aralia taibaiensis

Four new oleanane type triterpenoid saponins (1-4) and a known saponin (5) were isolated from the root bark of Aralia taibaiensis Z.Z. Wang et H.C. Zheng. The structures of the four new compounds were elucidated as 3-O-{β-d-glucopyranosyl-(1 → 2)-[β-d-glucopyranosyl-(1 → 3)]-β-d-glucurono-pyranosyl}-olean-11,13(18)-diene-28-oic acid 28-O-β-d-glucopyranosyl ester (1), 3-O-{β-d-gluco-pyranosyl-(1 → 3)-[α-l-arabinofuranosyl-(1 → 4)]-β-d-glucuronopyranosyl}-olean-11,13(18)-diene-28-oic acid 28-O-β-D-glucopyranosyl ester (2), 3-O-{β-d-glucopyranosyl-(1 → 2)-[α-l-arabinofuranosyl-(1 → 4)]-β-d-glucuronopyranosyl}-oleanolic acid 28-O-β-D-glucopyranosyl ester (3) and 3-O-{β-d-glucopyranosyl-(1 → 2)-[β-d-glucopyranosyl-(1 → 3)]-β-d-glucuronopyranosyl}-oleanolic acid 28-O-β-d-glucopyranosyl ester (4), on the basis of extensive spectral analysis and chemical evidence. Compounds 1-5 exhibited moderate effects on antioxidant and antiglycation activities, which correlated with treatment of diabetes mellitus.     

Antioxidant flavonoids from Epimedium wushanense

Two new flavonoids, wushanicaritin (1) and wushankaempferol (2), along with 24 known flavonoids were isolated from the whole herb of Epimedium wushanense T.S. Ying (Berberidaceae). On the basis of NMR and ESI-MS spectroscopic analysis, structures of compounds 1 and 2 were elucidated as 8-γ-hydroxy-γ,γ-dimethylpropyl-3,5,7-trihydroxy-4′- methoxyflavone and kaempferol 3-O-α-l-[2,3-di-O-β-d-(6-E-p-coumaroyl) glucopyranosyl]-rhamnopyranosyl-7-O-α-l-rhamnopyranoside, respectively. DPPH radical scavenging activity tests indicated that 1 (IC₅₀ 35.3 μM) exhibited antioxidant activity comparable to Vitamin C (IC₅₀ 32.0 μM), while 2 (IC₅₀ 443.7 μM) showed weak activity.     

Bioactive phenolics from the fruits of Livistona chinensis

This study investigated the antioxidant and cytotoxic activity of the phenolics isolated from the fruits of Livistona chinensis. Four new compounds, 1-{ω-isoferul[6- (4-hydroxybutyl)pentadecanoic acid]}-glycerol (1), E-[6′-(5″-hydroxypentyl)tricosyl]-4-hydroxy-3-methoxycinnamate (2), 2-(3′-hydroxy-5′-methoxyphenyl)-3-hydroxylmethyl-7-methoxy-2,3-dihydrobenzofuran-5- carboxylic acid (3), 7-hydroxy-5,4′-dimethoxy-2-arylbenzofuran (4), together with eleven known phenolics (5-15), were isolated and identified. Among these compounds, 1-4, 5-O-caffeoylshikimic acid (5), caffeic acid (7), and 3-O-caffeoylshikimic acid (8) showed potent antioxidant activity. 1-5, and 8 showed potent antiproliferative activities with IC₅₀ values among 5-150 μM against HepG2 human liver cancer, HL-60 human myeloid leukemia, K562 human myeloid leukemia, and CNE-1 human nasopharyngeal carcinoma cell lines. On the basis of these findings, it could be proposed that the fruits of L. chinensis may serve as attractive mines of powerful anticancer and antioxidant agents for various purposes.     

Dammarane-type saponins from Panax quinquefolium and their inhibition activity on human breast cancer MCF-7 cells

A new compound, named quinquefoloside-L_c (1), together with nine known compounds, was isolated from leaves of Panax quinquefolium, and its structure was elucidated as 3β,12β,20S-trihydroxy-25-methoxydammar-23-ene 3-O-β-d-glucopyranosyl (1 → 2) β-d-glucopyranosyl-20-O-β-d-xylopyanosyl (1 → 6) β-d-glucopyranoside (1), on the basis of MS, 1D-and 2D-NMR experiments as well as by chemical degradation. The cytotoxicity of these compounds against human breast cancer MCF-7 cell line was also tested by MTT method.     

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.     

Polyketides with antimicrobial activity from the solid culture of an endolichenic fungus Ulocladium sp

Two new polyketides, 7-hydroxy-3, 5-dimethyl-isochromen-1-one (1) and 6-hydroxy-8-methoxy-3a-methyl-3a,9b-dihydro-3H-furo[3,2-c]isochromene-2,5-dione (2), along with eleven known compounds, 5′-methoxy-6-methyl-biphenyl-3,4,3′-triol (3), 7-hydroxy-3-(2-hydroxy-propyl)-5-methyl-isochromen-1-one (4), rubralactone (5), isoaltenuene (6), altenuene (7), dihydroaltenuenes A (8), altenusin (9), alterlactone (10), 6-O-methylnorlichexanthone (11), norlichexanthone (12), and griseoxanthone C (13) were isolated from the culture of the endolichenic fungus Ulocladium sp. Compound 2 was obtained as a racemate with an unprecedented chemical skeleton. The NMR data assignments for 3 and 4 were achieved for the first time. Compounds 1-13 were screened for their antimicrobial and radical scavenging activities. Compound 1 showed some antifungal activity against Candida albicans SC 5314 with IC₅₀ of 97.93 ± 1.12 μM. Compounds 11-13 showed strong activity against Bacillus subtilis with IC₅₀ in the range of 1-5 μM. Compound 12 significantly inhibited the growth of methicillin-resistant Staphylococcus aureus with IC₅₀ of 20.95 ± 1.56 μM. Compounds 9 and 10 showed strong radical scavenging activity in comparison with vitamin C. The plausible biosynthetic pathways for compounds 1, 2, and 4-8 were discussed.     

A new triterpene saponin from Androsace integra

A new triterpene saponin, androsacin (1), along with two known compounds, ardisiacrispin A (2) and saxifragifolin A (3), were isolated from the whole plants of Androsace integra. The chemical structure of the new compound was elucidated as 3β-O-{β-D-glucopyranosyl-(1 → 4)-O-β-D-xylopyranosyl-(1 → 2)-O-β-D-glucopyranosyl-(1 → 4)-[O-β-D-glucopyranosyl-(1 → 2)]-α-L-arabinopyranosyl}-16α-hydroxy-13β,28-epoxy-olean-30-al on the basis of spectral evidence. Ardisiacrispin A (2) was cytotoxic toward HepG2 cancer cell with the GI₅₀ value of 1.56 μM.     

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.     

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.