Three new isoflavone glycosides from Tongmai granules

Three new isoflavone glycosides, 3′-methoxydaidzein-7,4′-di-O-β-d-glucopyranoside (1), biochanin A-8-C-β-d-apiofuranosyl-(1 → 6)-O-β-d-glucopyranoside (2), daidzein-7-O-β-d-glucopyranosyl-(1 → 4)-O-β-d-glucopyranoside (3), and a new natural isoflavone glycoside, daidzein-7-O-α-d-glucopyranosyl-(1 → 4)-O-β-d-glucopyranoside (4) were isolated along with 18 known isoflavones from the EtOAc and n-BuOH fractions of the aqueous extraction of Tongmai granules. All the isoflavones were obtained and determined for the first time from Tongmai granules. The structures of these compounds were elucidated by spectral methods. It was confirmed that the compounds 1–4 were originally from Puerariae Lobatae Radix based on HPLC-DAD analysis of the crude drug extract. The isoflavones isolated were tested for their antioxidative activities by measuring the capacities of scavenging the 2,2′-diphenyl-1-picrylhydrazyl radical.     

Two new compounds from the leaves of Indocalamus latifolius

Two new compounds, erythro-syringylglycerol-9-O-trans-4-hydroxycinnamate 7-O-β-d-glucopyranoside (1) and indocalatin A (2), together with three known ones, 5,7,3′-trihydroxy-6-C-β-d-digitoxopyranosyl-4′-O-β-d-glucopyranosyl flavonoid (3), 5,4′-dihydroxy-3′,5′-dimethoxy-7-O-[β-d-apiose-(1→2)]-β-d-glucopyranosyl flavonoid (4), and tricin-6-C-β-boivinopyranosyl-8-C-β-glucopyranoside (5), were isolated from the 95% EtOH extract of Indocalamus latifolius leaves. Their molecular structures were determined by UV, IR, HRESIMS, CD, and 1D and 2D NMR data analyses.     

Two new flavone glycosides from the seeds of Impatiens balsamina L.

Two new flavone glycosides were isolated from the seeds of Impatiens balsamina L. and their structures were determined as quercetin-3-O-[α-l-rhamnose-(1 → 2)-β-d-glucopyranosyl]-5-O-β-d-glucopyranoside (1), and quercetin-3-O-[(6?-O-caffeoyl)-α-l-rhamnose-(1 → 2)-β-d-glucopyranosyl]-5-O-β-d-glucopyranoside (2) on the basis of various spectral and chemical studies.     

Two new anthraquinone glycosides from the roots of Rheum palmatum

Two new anthraquinone glycosides, named 1-methyl-8-hydroxyl-9,10-anthraquinone-3-O-β-d-(6′-O-cinnamoyl)glucopyranoside (1) and rhein-8-O-β-d-[6′-O-(3″-methoxyl malonyl)]glucopyranoside (2), have been isolated from the roots of Rheum palmatum, together with seven known compounds, rhein-8-O-β-d-glucopyranoside (3), physcion-8-O-β-d-glucopyranoside (4), chrysophanol-8-O-β-d-glucopyranoside (5), aleo-emodin-8-O-β-d-glucopyranoside (6), emodin-8-O-β-d-glucopyranoside (7), aleo-emodin-ω-O-β-d-glucopyranoside (8), and emodin-1-O-β-d-glucopyranoside (9). Their structures were elucidated on the basis of chemical and spectral analysis.     

Two new flavonoid glycosides from the whole herbs of Hyssopus officinalis

Two new flavonoid glycosides, quercetin 7-O-β-d-apiofuranosyl-(1 → 2)-β-d-xylopyranoside (1) and quercetin 7-O-β-d-apiofuranosyl-(1 → 2)-β-d-xylopyranoside 3′-O-β-d-glucopyranoside (2), together with nine known flavonoids were isolated from the whole herbs of Hyssopus officinalis L. cultivated in Xinjiang Uygur Autonomous Region of China. All structures were characterized by the spectroscopic methods including UV, IR, ESI-MS, 1D, and 2D NMR. Their potent free radical scavenging activity against the stable 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical was evaluated.     

Three new C-flavonoids from Corallodiscus flabellata

Three new C-glycosylflavones, named 5,7,4′-trihydroxy-6-methoxy-8-C-[β-d-xylopyranosyl- (1 → 2)]-β-d-glucopyranosyl flavonoside (1), 5,7,4′-trihydroxy-8-methoxy-6-C-[β-d-xylopyranosyl-(1 → 2)]-β-d-glucopyranosyl flavonoside (2), and 5,3′,4′-trihydroxy-7,8-dimethoxy-6-C-[β-d-xylopyranosyl-(1 → 2)]-β-d-glucopyranosyl flavonoside (3), along with two known compounds 5,4′-dihydroxy-7-methoxy-6-C-glucopyranosyl-flavonoside (4), 3-methoxy-4-hydroxymethyl benzoate (5) were isolated from 70% acetone extract of Corallodiscus flabellata. Their structures were identified on the basis of spectroscopic techniques and chemical methods.     

Alkaloids from Clematis manshurica Rupr.

Three new alkaloids together with two known compounds have been isolated from the roots of Clematis manshurica. On the basis of their spectroscopic and chemical evidence, the new compounds were elucidated as methyl 7-ethoxy-3-indolecarbonate (2), methyl 7-O-α-l-rhamnopyranosyl-(1 → 6)-β-d-glucopyranosyl 3-indolecarbonate (3) and α-l-rhamnopyranosyl-(1 → 6)-β-d-glucopyranosyl 3-indolecarbonate (4).     

Steroidal alkaloids from the bulbs of Fritillaria unibracteata

Two new steroidal alkaloids peimisine-3-O-β-d-glucopyranoside (1) and puqiedinone-3-O-β-d-glucopyranoside (3), together with three known compounds peimisine (2), puqiedinone (4), and puqiedine (5), were isolated and characterized from the bulbs of Fritillaria unibracteata. Their structures were fully elucidated by spectroscopic and chemical methods. Compound 1 showed moderate protection effect on neurotoxicity of PC12 cell lines induced by rotenone.     

Isoflavonoid glycosides from the flowers of Pueraria lobata

Pueraria lobata flower is a medicinal herb for treating intoxication, hepatic, and gastrointestinal tract lesions induced by alcohol. This study aims to investigate the isoflavonoid glycosides in P. lobata flowers. Two new isoflavone compounds were isolated from the extract of P. lobata flowers. Their structures were determined to be 5,6,7,4′-tetrahydroxyisoflavone-6,7-di-O-β-d-glucopyranoside and 5,6,7-trihydroxy-4′-methoxyisoflavone-6,7-di-O-β-d-glucopyranoside on the basis of spectroscopic means including HR-ESI-MS, UV, IR, ¹H, and ¹³C NMR.     

Two new C21 steroidal glycosides from Cynanchum wallichii Wight

Two new C₂₁ steroidal glycosides, characterized with caudatin as the aglycone moiety and 2,6-dideoxy-pyranoses as component sugars, have been isolated from the roots of Cynanchum wallichii Wight. Their structures were elucidated as caudatin-3-O-β-d-cymaropyranosyl-(1 → 4)-β-d-digitoxopyranoside (1) and caudatin-3-O-β-d-oleandropyranosyl-(1 → 4)-β-d-cymaropyranoside (2) by spectroscopic evidence.     

A new flavonoid glucoside from Rhododendron seniavinii

The leaves of Rhododendron seniavinii Maxim with little phytochemical information are used as folk remedies for the treatment of acute and chronic bronchitis in China. In our pursuing for the biologically active chemical constituents in the leaves, a new flavonoid glycoside 5,7,3′-trimethoxy-quercetin-3-O-β-d-glucopyranoside (1) was isolated from the water extract of its leaves, together with two known compounds 5,7,3′-trimethoxy-quercetin (2) and ovafolinin B-9′-O-β-d-glucopyranoside (3). The structures of the new flavonoid glucoside as well as two known compounds were elucidated by spectroscopic and chemical methods.     

Two new terpenoid glucosides from Aster flaccidus

Two new terpenoid glucosides, namely 2-O-β-d-glucopyranoside-vicodiol (1) and 10-O-β-d-glucopyranoside-oplopanone (2), along with seven known compounds, were isolated from the aerial part of Aster flaccidus (composite), a traditional Chinese herb medicine. The structures of 1 and 2 were established by spectroscopic methods, especially 2D NMR experiments.     

Two new sesquiterpene glycosides from Pogostemon cablin

Two new rearranged patchoulane sesquiterpene glycosides, 3α-hydroxypatchoulol 3-O-β-d-glucopyranoside (1) and 15-hydroxypatchoulol 15-O-β-d-glucopyranoside (2) together with rubusoside, a known diterpene glycoside, were isolated from the ethanol extract of the whole plant of Pogostemon cablin (Blanco) Benth. The structures of 1 and 2 were elucidated by spectroscopic analysis.     

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.     

Two new compounds from Urena lobata L.

Two new compounds 1 and 2 have been isolated from the aerial parts of Urena lobata L. The structures of the two new compounds were established as ceplignan-4-O-β-d-glucoside (1) and 2,5-dihydroxy benzoic acid-7-(2,6-dimethyl-6-hydroxy-2,7-octadienoic acid) anhydride-5-O-β-d-apiofuranosyl(1 → 2)-β-d-glucoside (urenoside A) (2), on the basis of chemical and spectral evidence, including 1D and 2D NMR spectroscopic data as well as mass spectrometry (HR-ESI-MS).     

The synthesis of pennogenin 3-O-β-d-glucopyranosyl-(1 → 3)-[α-l-rhamnopyranosyl-(1 → 2)]-β-d-glucopyranoside

Pennogenin 3-O-β-d-glucopyranosyl-(1 → 3)-[α-l-rhamnopyranosyl-(1 → 2)]-β-d-glucopyranoside, a monodesmosidic saponin isolated from Paris polyphylla Smith var. yunnanensis with promised antitumor activities, was firstly synthesized from glucoside thiol via nine steps and with 27% overall yield.     

Two new phenols from Lysimachia patungensis

Two new phenols, methyl 3-(2-O-β-d-glucopyranosyl-3-hydroxy-5-methoxyphenyl) propionate (1) and myricetin-3,3′,5′-tri-O-α-l-rhamnopyranoside (2), together with six known phenols compounds (3–8), were isolated from the whole plant of Lysimachia patungensis Hand.-Mazz. Their structures were elucidated on the basis of the interpretation of spectroscopic data, viz., ESI-MS, HR-TOF-MS, UV, IR, and NMR. All the known phenols were isolated from the genus Lysimachia for the first time. A preliminary bioassay revealed that compounds 3 and 7 exhibited significant protective effects against hydrogen peroxide-induced damage in human retinal endothelial cells (HRECs) with the concentration of 10 μM, respectively. Compound 1 showed moderate activity against the HRECs damage at 100 μM.     

Isolation,structural elucidation of flavonoid constituents from Leptadenia pyrotechnica and evaluation of their toxicity and antitumor activity

An investigation of Leptadenia pyrotechnica (Forsk.) Decne (Asclepiadaceace) chemical constituents led to the isolation of six flavonoids, kaempferol-3-O-α-l-rhamnopyranosyl (1′″→6″)-O-β-d-glucopyranoside (E-I.1), kaempferol-3-O-β-d-rhamnopyranosyl (1′″→6″)-O-β-d-glucopyranoside (E-I.2), texasin-7-O-β-d-glucopyranoside E-II.2, kaempferol-3-O-β-d-glucopyranoside (E-III.1), kaempferol (E-IV.1) and kaempferide-3-O-α-l-rhamnopyranosyl (1′″→6″)-O-β-d-glucopyranoside (E-I.1a). The isolation of these compounds was carried out using Sephadex LH-20 low pressure liquid chromatography (LPLC), preparative paper chromatography (PC), and high performance liquid chromatography (HPLC). The chemical structures of the isolated compounds were established by mass spectrometry (FAB- and EI- techniques), nuclear magnetic resonance NMR (¹H-, ¹³C- and COSY) spectral data and ultraviolet (UV) spectroscopic techniques. The acute toxicity of total alcoholic and total flavonoid extracts were examined by brine shrimp. The LC₅₀ values were 11.89 and 84.14 ppm for the total alcoholic and total flavonoid extracts, respectively. The mortality rates of the isolated flavonoid fractions of E-I, E-I.1, E-I.2 represent the higher percentages of mortality compared with the rest of the flavonoid fractions. The plant exhibited activity as an antitumor agent in the initial potato disc screen.     

Note: Xanthone glycosides from Swertia franchetiana

A new xanthone glycoside (1) has been isolated from Swertia franchetiana together with five known xanthone glycosides. Their structures were elucidated as 7-O-[β-d-xylopyranosyl-(1→2)-β-d-xylopyranosyl]-1,7,8-trihydroxy-3-methoxyxanthone (1), 7-O-[α-l-rhamnopyranosyl-(1→2)-β-d-xylopyranosyl]-1,7,8-trihydroxy-3-methoxyxanthone (2), 8-O-β-d-glucopyranosyl-1,3,5,8-tetrahydroxyxanthone (3), 1-O-β-d-glucopyranosyl-1-hydroxy-3,7,8-trimethoxyxanthone (4), 1-O-[β-d-xylopyranosyl-(1→6)-β-d-glucopyranosyl]-1-hydroxy-2,3,5-trimethoxyxanthone (5) and 1-O-[β-d-xylopyranosyl-(1→6)-β-d-glucopyranosyl]-1-hydroxy-3,5-dimethoxyxanthone (6) on the basis of spectroscopic evidence.     

Two new triterpenoid saponins from Ilex cornuta

Two new triterpenoid saponins (1 and 2) were isolated from the stems of Ilex cornuta, along with two known triterpenoids (3 and 4). The structures of compounds 1 and 2 were determined as ursane-12,19-diene-28-oic acid 3β-O-β-d-glucuronopyranoside-6-O-methyl ester (1), 3α,23α-dihydroxy-olean-9(11),12-diene-28-oic acid 28-O-β-d-glucopyranosyl ester (2), on the basis of hydrolysis and spectral evidence, including 1D and 2D NMR and high resolution electrospray ionization mass spectrometry (HR-ESI-MS) analyses. Protective effects of compounds 1–4 were tested against H₂O₂-induced H9c2 cardiomyocyte injury, and the data showed that all these compounds had no cell-protective effect.