Three new flavanoids from artificially induced dragon’s blood of Dracaena cambodiana

Three new flavanoids, (2R)-7,4′-dihydroxy-8-methylflavan (1), (2R)-7,4′-dihydroxy-6-methylflavan (2), and (3R)-7,3′,4′-trihydroxyhomoisoflavan (3), together with seven known compounds (4–10), were isolated from artificially induced dragon’s blood of Dracaena cambodiana, and their structures were determined based on HR-ESI-MS and extensive spectroscopic techniques (UV, IR, 1D-, and 2D-NMR). Compound 2 exhibited weak cytotoxicity against BEL-7402 cells line with the IC₅₀ value of 39.2 μM. In addition, compound 3 showed significant acetylcholinesterase (AChE) inhibitory activity.     

New dianthramide and cinnamic ester glucosides from the roots of Aconitum carmichaelii

Four new compounds N-salicyl-3-hydroxyanthranilic acid methyl ester (1), N-(2′-dehydroxysalicyl)-3-hydroxyanthranilic acid methyl ester (2), methyl-4-β-D-allopyranosyl-ferulate (3), and methyl-4-β-D-gulopyranosyl-cinnamate (4), along with six known compounds (5–10), were isolated from the roots of Aconitum carmichelii Debx. Their structures were elucidated on the basis of spectral data analysis, including 1D, 2D-NMR, and HR-ESI-MS. Compounds 1 and 2 showed the inhibition of nitric oxide (NO) production with IC₅₀ values of 9.13 and 19.94 μM, respectively.     

Two new antioxidant diarylheptanoids from the fruits of Alpinia oxyphylla

Two new diarylheptanoids, 1-(3′,5′-dihydroxy-4′-methoxyphenyl)-7-phenyl-3-heptanone (1) and 1-(2′,4′-dihydroxy-3′-methoxyphenyl)-7-(4″-methoxyphenyl)-3-heptanone (2), along with known diarylheptanoid yakuchinone A (3), and five flavanoids, tectochrysin (4), chrysin (5), izalpinin (6), kaempferol 7, 4′-dimethyl ether (7), and kaempferide (8) were isolated from the fruits of Alpinia oxyphylla Miq. Their structures were determined by means of spectroscopic methods. Antioxidant activities of all the isolated compounds were evaluated using a 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay. Compounds 1–3 and 6–8 exhibited potent antioxidant activities in the DPPH assay.     

New anthraquinone dimer from the root bark of Cassia artemisioides (Gaudich. Ex. DC) Randell

The phytochemical investigation of the root bark of Cassia artemisioides (Gaudich. Ex. DC) Randell resulted in the isolation of one new anthraquinone 1,1′-dihydroxy-3,3′-dimethyl-8,8′-dimethoxy-6,6′-O-bianthraquinone (1) along with four known anthraquinones 1,6-dihydroxy-8-methoxy-3-methylanthraquinone (2), 1-hydroxy-8-methoxy-3-methylanthraquinone (3), 1,8-dihydroxy-6-methoxy-3-methylanthraquinone (4), and 1,6,8-trihydroxy-3-methylanthraquinone (5). The structures of the compounds were elucidated using spectroscopic techniques including 1D and 2D NMR. The compounds were evaluated for antioxidant activity. 1,6,8-Trihydroxy-3-methyl anthraquinone (5) showed good activity among the tested compounds.     

Triterpenoids with antioxidant activities from Myricaria squamosa

A new triterpenoid, namely myricarin C (compound 1), together with three known compounds myricarin A (compound 2) and myricarin B (compound 3), 3α-hydroxy-D-friedoolean-14-en-28-oic acid (compound 4), was isolated from the overground part of Myricaria squamosa. Compound 2 and compound 3 existed in the solution by the form of cis-trans isomers. Their structures were elucidated by means of extensive spectroscopic methods, including 1D-NMR, 2D-NMR, and HR-ESI-MS. The antioxidant properties of all compounds were calculated based on the DPPH radical scavenging activities. Results showed that myricarin A and myricarin C had general antioxidant activities with EC₅₀ values of 40.90 μg/ml, 42.22 μg/ml, respectively, compared to the control, rutin (5.17 μg/ml). The EC₅₀ values of myricarin B was 195.81 μg/ml. Compound 4 had no antioxidant activities.     

A new cyclolignan glycoside from the tubers of Pinellia ternata

A new 2,7′-type cyclolignan glycoside, cyclolignanyingoside A (1), together with six known compounds (2–7) were isolated from the tubers of Pinellia ternata (Thunb.) Breit. The structure of 1 was elucidated on the basis of chemical and spectral analysis, including 1D, 2D NMR analyses, HR-ESI-MS, and CD spectrometry. The cytotoxic, antioxidant and tyrosinase-inhibiting activities of all the isolates were determined. However, all the isolates exhibited no activity on the selected cell lines (Hep-3B, Bcap-37, and MCF-7). In addition, compounds 1–3 and 7 exhibited strong 2,2′-azino-bis (3-ethylbenzothiazoline-6-sulphonic acid) free radical scavenging activity, and compounds 2 and 4 showed a moderate mushroom tyrsinase inhibitory activity.     

New phenylpropanoid esters of sucrose from <Emphasis Type="Italic">Polygonum hydropiper</Emphasis> and their antioxidant activity

By various chromatographic methods, two new phenylpropanoid esters of sucrose named hidropiperosides A (1) and B (2), and three known compounds as vanicosides A (3), B (4), and E (5) were isolated from the methanolic extract of the whole plant of Polygonum hydropiper L. (Polygonaceae). Their structures were elucidated by extensive spectroscopic methods including 1D-and 2D-NMR experiments, as well as ESI-MS analysis. All the isolated compounds were tested for their antioxidant activity in the 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging assay system. Among them, compounds 2 and 3 showed significant antioxidant activity with their SC₅₀ values of 23.4 and 26.7 μg/mL, respectively.     

Antioxidant and cytotoxic lignans from the roots of Bupleurum chinense

In the search for biologically active compounds from the roots of Bupleurum chinense D C., phytochemical investigation of its ethanol extract led to the isolation and identification of a new 8-O-4′ neolignan glucoside, saikolignanoside A (1), along with eight known lignans (2–9). Their structures were determined on the basis of IR, UV, HRESIMS, and NMR spectroscopic analyses. The antioxidant and cytotoxic effects of isolated compounds were evaluated in vitro. The isolated compounds (IC₅₀ > 200 μM) did not display 2, 2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity. Whereas compounds 1–2, 5, 7, and 9 exhibited potent 2, 2′-azinobis(3-ethyl-benzothiazoline-6-sulfonic acid) (ABTS) free radical scavenging properties with IC₅₀ values ranging from 8.34 to 15.24 μM, while compounds 3–4, 6, 8 showed moderate properties. In addition, all compounds were evaluated for cytotoxicities against A549, HepG2, U251, Bcap-37, and MCF-7 cell lines. Compounds 5 and 9 (IC_50?相似文献   

A New Sesquiterpene Lactone Glucoside from Ixeris Sonchifolia

Abstract

A new sesquiterpene lactone glucoside, Ixerin Z₁ (1), was isolated from the whole plants of Ixeris sonchifolia (Bge.) Hance, along with 15 known compounds. The structure of 1 was elucidated as 1(10),3,11(13)-guaiatriene-12,6-olide-2- one-3-O-[6′-(p-hydroxyphenylaceryl)]-gluco-pyranoside by spectroscopic methods including 2D-NMR techniques.     

Two new lignans from the aerial part of Vitex negundo

A new phenyldihydronaphthalene-type lignan, (3R,4S)-6-hydroxy-4-(4-hydroxy- 3-methoxyphenyl)-5,7-dimethoxy-3,4-dihydro-2-naphthaldehyde-3a-O-β-d-glucopyranoside (1), and a new phenylnaphthalene-type lignan, 6,7,4′-trihydroxy-3′-methoxy-2,3- cycloligna-1,4-dien-2a,3a-olide (2), along with 10-known lignan derivatives (3–12) were isolated from the aerial part of Vitex negundo var. heterophylla. Their structures were established by comprehensive 1D- and 2D-NMR spectroscopic analyses.     

Antioxidant and Antitumor Promoting Activities of the Flavonoids from Hedychium thyrsiforme

Abstract

Five flavonoids, including 3,7,4′-trimethoxy-5-hydroxyflavone (1), 3,4′-dimethoxy-5,7-dihydroxyflavone (2), 5,7,4′-trimethoxy-3-hydroxyflavone (3), 3,5,7,4′-tetramethoxyflavone (4), and 7,4′-dimethoxy-3,5-dihydroxyflavone (5), were isolated from the rhizome of Hedychium thyrsiforme and assayed for antioxidant and antitumor promoting activities. The antioxidant assays showed that 5,7,4′-trimethoxy-3-hydroxyflavone, 7,4′-dimethoxy-3,5-dihydroxyflavone and 3,4′-dimethoxy-5,7-dihydroxyflavone had strong activities. Only two compounds, 5,7,4′-trimethoxy-3-hychoxyflavone and 7,4′-dimethoxy-3,5-dihydroxyflavone, were found to be strong 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical scavengers with fifty percent inhibition concentration (IC₅₀) values of 92 and 119 μM, respectively. Antitumor promoting assays indicated that all the flavonoids showed strong inhibition activity towards Epstein-Barr virus (EBV) activation in Raji cells.     

Isolation and characterization of secondary metabolites from Plumeria obtusa

Chromatographic purification of the methanolic extract of Plumeria obtusa yielded two new iridoid obtusadoids A (1) and B (2), along with eight known compounds plumieridin A (3), plumieridine (4), 1α-plumieride (5), 15-demethylplumieride (6), rel-(3R,3′S,4R,4′S)-3,3′,4,4′-tetrahydro-6,6′-dimethoxy[3,3′-bi-2H-benzopyran]-4,4′-diol (7), glochiflavanoside B (8), oleanolic acid (9), and methyl coumarate (10). The structures of all the isolates (1–10) were determined by NMR spectroscopy and mass spectrometry. The data of known compounds (3–10) were further compared with the reported data for these compounds.     

New antioxidant phenylethanol glycosides from Torenia concolor

Two new phenylethanol glycosides, phenylethyl-O-α-l-rhamnopyranosyl-(1 → 2)-β-d-glucopyranoside (torenoside A, 1) and 2′-O-3,4-dihydroxy-β-phenylethoxy-O-α-l-rhamnopyranosyl-(1″ → 3′)-(4′-O-caffeoyl)-β-d-glucopyranoside (torenoside B, 2), along with the 17 known compounds (3–19) were isolated from Torenia concolor. Those structures were established on the basis of spectroscopic analysis including NMR spectroscopic techniques (¹³C, ¹H, ¹H–¹H COSY, HMQC, HMBC, TOCSY, and NOESY). Moreover, phenylethanol glycosides 3–6 exhibited significant antioxidant activities in DPPH radical scavenging assay.     

Flavonoids from silkworm droppings and their promotional activities on heme oxygenase-1

A new flavane glucoside, 7,2′-dihydroxy-8-hydroxyethyl-4′-methoxyflavane-2′-O-β-d-glucopyranoside (3), along with three known flavonoids, 7,2′-dihydroxy-8-prenyl-4′-methoxyflavane (1), euchrenone a₇ (2), and 7,2′-dihydroxy-8-prenyl-4′-methoxy-2′-O-β-d-glucopyranosylflavane (4), was isolated from silkworm droppings. The structures of the compounds were elucidated on the basis of 1D and 2D NMR spectroscopic analyses and optical rotational characteristics. The compounds isolated from silkworm droppings were evaluated for their effects on heme oxygenase-1 (HO-1) activity. Compounds 1 and 3 increased the expression of HO-1 in HepG2 cells. HO-1 is an antioxidant enzyme that catabolizes heme to carbon monoxide, free iron, and biliverdin, all of which are involved in the suppression of inflammatory mediators.     

Three new benzolactones from Lavandula angustifolia and their bioactivities

Three new benzolactones (1–3), together with four known ones (4–7), were isolated from the whole herb of Lavandula angustifolia. Their structures were established on the basis of detailed spectroscopic analysis (1D- and 2D-NMR, HRESIMS, UV, and IR) and comparison with data reported in the literature. New compounds were evaluated for their anti-tobacco mosaic virus (TMV) activities and cytotoxic activities. The results revealed that compounds 1–3 showed obvious anti-TMV activities with inhibition rates of 26.9, 30.2, and 28.4%, which were at the same grade as positive control. Compounds 1–3 also showed weak inhibitory activities against some tested human tumor cell lines with IC₅₀ values in the range of 32.1–7.6 μM.     

A new cytotoxic homoisoflavonoid from Dracaena cambodiana

A new homoisoflavonoid, named cambodianol (1), together with the two known flavanes, (2S)-7,3′-dihydroxy-4′-methoxy-8-methylflavane (2) and (2R)-7,4′-dihydroxy-8-methylflavane (3), were isolated from the stems of Dracaena cambodiana. Their structures were determined based on HR-ESI-MS and spectroscopic techniques (UV, IR, 1D-, and 2D-NMR). Compound 1 exhibited significant cytotoxic activities against K562 and SGC-7901 with the IC₅₀ values of 1.4 and 2.9 μg/ml, respectively.     

A new antioxidant compound from Capparis spinosa

An activity-directed fractionation and purification process was used to isolate 1,1-diphenyl-2-picrylhydrazyl radical (DPPH?) scavenging components from fruits of Capparis spinosa L. (Capparaeae). Ethyl acetate and aqueous fractions showed greater DPPH? scavenging activities compared to the petroleum ether fractions. The ethyl acetate fraction was subjected to purification using column chromatography. A new antioxidant cappariside (4-hydroxy-5-methylfuran-3-carboxylic acid, 1), together with seven known organic acids (2–8) for the first time from plants of genus Capparis and four known organic acids (9–12) were isolated from C. spinosa. The structures were elucidated by extensive analysis of 1D- and 2D-NMR spectroscopic. In addition, compounds 1, 2, 4, 5, 9, 10 and 12 indicated strong scavenging capacity for 1,1-diphenyl-2-picrylhydrazyl (DPPH) radicals with a SC₅₀ value of 0.204?±?0.002, 0.007?±?0.0, 0.011?±?0.0, 0.044?±?0.0016, 0.032?±?0.0, 0.090?±?0.001, and 0.350?±?0.017?mM, respectively.     

Homoisoflavanones with estrogenic activity from the rhizomes of Polygonatum sibiricum

A new homoisoflavanone, (3R)-5-hydroxy-7-methoxyl-3-(2′-hydroxy-4′- methoxybenzyl)-chroman-4-one (1), together with six known analogs, were isolated from the rhizomes of Polygonatum sibiricum. Their structures were elucidated on the basis of extensive spectroscopic analysis. All compounds were tested for their estrogenic activity using the MCF-7 estrogenresponsive human breast cancer cell lines. At a dose of 0.1 μmol/L, compounds 1–7 exhibited significant proliferative effects on MCF-7 cells compared with E₂. The molecular docking study results indicated that the activity of compounds 3, 5, 6, and 7 may be the binding with ERR.     

Phenolic compounds from Bletilla striata

Two new malic acid derivatives, namely eucomic acid 1-methyl ester (2) and 6′′′-acetylmilitaline (7), together with ten known compounds (1, 3–6, 8–12), were isolated from the dry tubers of Bletilla striata (Thunb.) Reichb. F., a perennial traditional Chinese medicinal herb, which was used for the treatment of pneumonophthisis, pneumonorrhagia, tuberculosis, and hemorrhage of the stomach or lung. Their structures were elucidated by spectroscopic analyses, including 1D-, 2D-NMR, and HR-ESI-MS.     

A new sesquiterpene lactone glycoside and a new quinic acid methyl ester from Patrinia villosa

A new sesquiterpene lactone glycoside (1) and a new quinic acid methyl ester (2) were isolated from Patrinia villosa, together with another two known compounds chlorogenic acid n-butyl ester (3), 3, 4-di-O-caffeoylquinic acid methyl ester (4). Their structures were established using 1D/2D-NMR spectroscopy, mass spectrometry, and comparing with spectroscopic data reported in the literature.