Aromatic glycosides from the flower buds of Lonicera japonica

Six new glycosides (1–6) have been isolated from the flower buds of Lonicera japonica. Their structures including the absolute configurations were determined by spectroscopic and chemical methods as ( ? )-2-hydroxy-5-methoxybenzoic acid 2-O-β-d-(6-O-benzoyl)-glucopyranoside (1), ( ? )-4-hydroxy-3,5-dimethoxybenzoic acid 4-O-β-d-(6-O-benzoyl)-glucopyranoside (2), ( ? )-(E)-3,5-dimethoxyphenylpropenoic acid 4-O-β-d-(6-O-benzoyl)-glucopyranoside (3), ( ? )-(7S,8R)-(4-hydroxyphenylglycerol 9-O-β-d-[6-O-(E)-4-hydroxy-3,5-dimethoxyphenylpropenoyl]-glucopyranoside (4), ( ? )-(7S,8R)-(4-hydroxy-3-methoxyphenylglycerol 9-O-β-d-[6-O-(E)-4-hydroxy-3,5-dimethoxyphenylpropenoyl]-glucopyranoside (5), and ( ? )-4-hydroxy-3-methoxyphenol β-d-{6-O-[4-O-(7S,8R)-(4-hydroxy-3-methoxyphenylglycerol-8-yl)-3-methoxybenzoyl]}-glucopyranoside (6), respectively.     

Aromatic glycosides from the whole plants of Iris japonica

Phytochemical investigation on the whole plants of Iris japonica led to the isolation of four new aromatic glycosides. Their structures including the absolute configurations were determined by spectroscopic and chemical methods as (?)-4-hydroxy-3-methoxy acetophenone 4-O-β-d-{6-O-[4-O-(7R,8S)-(4-hydroxy-3-methoxyphenylglycerol-8-yl)-3-methoxybenzoyl]}-glucopyranoside (1), (?)-4-hydroxy-3-methoxy acetophenone 4-O-β-d-{6-O-[4-O-(7S,8R)-(4-hydroxy-3-methoxyphenylglycerol-8-yl)-3-methoxybenzoyl]}-glucopyranoside (2), (?)-4-hydroxy-3-methoxy acetophenone 4-O-β-d-{6-O-[4-O-(7R,8R)-(4-hydroxy-3-methoxyphenylglycerol-8-yl)-3-methoxybenzoyl]}-glucopyranoside (3), (?)-4-hydroxy-3-methoxy acetophenone 4-O-β-d-{6-O-[4-O-(7S,8S)-(4-hydroxy-3-methoxyphenylglycerol-8-yl)-3-methoxybenzoyl]}-glucopyranoside (4), respectively.     

Ceramides and cerebrosides from the marine bryozoan Bugula neritina inhabiting South China Sea

From the marine bryozoan Bugula neritina inhabiting South China Sea, a new ceramide named (2S,3R,4E)-2-(14′-methyl-pentadecanoylamino)-4-octadecene-l,3-diol (1) and a new cerebroside named 1-O-(β-d-glucopyranosyl)-(2S,3R,4E)-2-(heptadecanoylamino)-4-octadecene-l,3-diol (6), together with one known ceramide (2) and three known cerebrosides (3, 4, and 5), were isolated. Their structures were deduced by extensive spectral analysis and chemical evidences. Compound 1 is branched with a methyl [–CH(CH₃)₂] in the fatty acid moiety, which is a rare structural feature among ceramides. Compound 6 is a new cerebroside with 17 carbons in the fatty acid moiety, while 5 is a new natural product which was isolated from a natural origin for the first time.     

Two novel flavanes from the leaves of Morus alba L.

Two new flavanes, (2R,4S)-2′,4′-dihydroxy-2H-furan-(3″,4″:8,7)-flavan-4-ol (1) and (2S)-2′,4′-dihydroxy-7-methoxyl-8-butyricflavane (2), together with four known flavonoids, were isolated from the leaves of Morus alba L. Their structures were determined on the basis of spectroscopic analysis.     

A new thiophene and two new monoterpenoids from Xanthium sibiricum

Three new compounds (1–3), together with six known compounds (4–9), were isolated from the fruits of Xanthium sibiricum. The structures and the absolute configurations of sibiricumthionol (1), (+)-(5Z)-6-methyl-2-ethenyl-5-hepten-1,2,7-triol [(+)-2], ( ? )-(5Z)-6-methyl-2-ethenyl-5-hepten-1,2,7-triol [( ? )-2], (2E,4E,1′S, 2′R, 4′S, 6′R)-dihydrophaseic acid (3), (+)-xanthienopyran [(+)-4] and ( ? )-xanthienopyran [( ? )-4] were established by extensive spectroscopic analyses, X-ray crystallographic analysis, ECCD analysis and ECD calculations. Caffeic acid (7) and caffeic acid ethyl ester (8) weekly inhibited α-glucosidase enzymatic activity by 44.5% and 40.2%, respectively, at 40 μM. Protocatechuic acid (9) selectively exhibited cytotoxicity against HepG2 cell lines, with an IC₅₀ value of 2.92 μM.     

Note: A new compound from Rhododendren anthopogonosides maxim

A new compound, (2R)-4-phenyl-2-O-[β-d-xylopyranosyl(1→6)-β-d-glucopyranosyl]butane (1), has been isolated from the aerial parts of Rhododendren anthopogonoides, together with two known compounds, fraxin (2), and lyoniside (3). Their structures were determined by means of physico-chemical evidence and spectral analyses, including UV, IR, HR-FABMS, ¹H and ¹³C NMR, and 2D NMR data.     

Flavans from the leaf of Ilex centrochinensis

Phytochemical investigation of the leaf of Ilex centrochinensis led to the isolation and characterization of four flavans, one flavanone (5), and one flavone (6), including a new compound whose structure was elucidated as (2S)-5,3′,4′-trihydroxy-7-methoxyflavan (1) and a new natural product whose structure was elucidated as (2S)-5-hydroxy-7,3′,4′-trimethoxyflavan (4) on the basis of spectroscopic methods especially 1D and 2D NMR, CD, and mass spectral analyses. Compounds 1 and 4 exhibited weak cytotoxic activity against Huh7 cell line and no cytotoxic activity against Caco-2 cell line.     

New phenolic glycosides from Pilea cavaleriei

Five new phenolic glycosides, 2-hydroxy-(2′E)-prenyl benzoate-2,4′-di-O-β-d-glucopyranoside (1), 2-hydroxy-(2′E)-prenyl benzoate-2-O-α-l-arabinopyranosyl-(1 → 6)-β-d-glucopyranoside (2), 4-methylphenol-1-O-α-l-rhamnopyranosyl-(1 → 6)-β-d-glucopyranoside (3), 4-methylphenol-1-O-α-l-arabinopyranosyl-(1 → 6)-β-d-glucopyranoside (4), and 3,5-dimethoxyphenol-1-O-β-d-apiofuranosyl-(1 → 2)-β-d-glucopyranoside (5), together with six known glycosides (6–11), were isolated from the n-BuOH fraction of the EtOH extract of Pilea cavaleriei Levl subsp. cavaleriei. Their structures were elucidated by extensive spectroscopic analysis, including 1D and 2D NMR spectroscopy as well as HR-ESI-MS, and chemical evidences. All these compounds were isolated from the genus Pilea for the first time.     

A new meta-homoisoflavane from the fresh stems of dracaena cochinchinensis

A new meta-homoisoflavane, 10,11-dihydroxydracaenone C (1), together with 7,4′-dihydroxyflavone (2), 7,4′-dihydroxyflavane (3), 4,4′-dihydroxy-2-methoxychalcone (4), 4,4′-dihydroxy-2-methoxydihydrochalcone (5), 7,4′-dihydrohomoisoflavanone (6), 7,4′-homoisoflavane (7), lophenol (8), β-sitosterol (9), stigma-5, 22-diene-3-ol (10), 1-(4′-O-β-d-glucopyranosyl)benzyl-ethan-2-ol (11), 3,4-dihydoxy-1-allylbenezene-4-O-α-l-rhamnopyranosyl-(1 → 6)-O-β-d-glucopyranoside (12), 1-hydroxy-3,4,5-trimethoxybenzene-1-O-α-l-apiopyranosyl-(1 → 6)-O-β-d-glucopyranoside (13), and tachioside (14) have been isolated from the fresh stems of Dracaena cochinchinensis. Their structures have been established by spectroscopic analysis, especially by 2D NMR. This is the first time compounds 11, 13, 14 have been isolated from Dracaena.     

Flavonoids from the leaves of Pleioblastus argenteastriatus

A new flavonoid, 5,7,3′-trihydroxy-6-C-β-d-digitoxopyranosyl-4′-O-β-d-glucopyranosyl flavonoside (1), along with four known flavonoids 5,7,4′-trihydroxy-3′,5′-dimethoxy flavone (2), 5,3′,4′-trihydroxy-7-O-β-d-glucopyranosyl flavonoside (3), 5,4′-dihydroxy-3′,5′-dimethoxy-7-O-β-d-glucopyranosyl flavonoside (4), 5,3′,4′-trihydroxy-6-C-[β-d-glucopyranosyl-(1 → 6)]-β-d-glucopyranosyl flavonoside (5) were isolated from 95% EtOH extract of the leaves of Pleioblastus argenteastriatus. Their structures were determined on the basis of spectroscopic techniques and chemical methods.     

Two new 5,8-quinoflavans from the leaf of Ilex centrochinensis

Two new 5,8-quinoflavans were isolated from the leaf of Ilex centrochinensis, and their structures were elucidated as (2R)-7,3′,4′-trimethoxy-5,8-quinoflavan and (2S)-7-methoxy-4′-hydroxy-5,8-quinoflavan on the basis of spectroscopic methods, especially 1D and 2D NMR, CD, and mass spectral analyses. Both of them exhibited weak cytotoxic activity against HuH7 cell lines and no cytotoxic activity against CaCO-2 cell lines.     

Three new monoterpene glycosides from the roots of Paeonia lactiflora

Three new monoterpene glycosides, 2′-O-benzoylpaeoniflorin, albiflorin R₂, and albiflorin R₃ (1–3) were isolated from the roots of Paeonia lactiflora. Their structures were elucidated on the basis of spectroscopic means including one- and two-dimensional NMR experiments.     

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.     

Antioxidant and α-amylase inhibitory activities of extract and isolates from Zygogynum pancheri subsp. arrhantum

One new sesquiterpenoid (5R^*,8R^*,9R^*,10R^*)-cinnamolide (8), and seven known compounds, 5-hydroxy-7-methoxyflavonone (1), 8-hydroxy-3-(4′-hydroxyphenyl)-6,7-(2″,2″-dimethylchromene)-tetralone (2), 8-hydroxy-3-(3′,4′-dihydroxyphenyl)-6,7-(2″,2″-dimethylchromene)-tetralone (3), 1β-E-O-p-methoxycinnamoyl-bemadienolide (4), 1β-O-(E-cinnamoyl)-6α-hydroxy-9-epi-polygodial (5), 1β-O-(E-cinnamoyl)-6α-hydroxypolygodial (6), and 1β-O-E-cinnamoylpolygodial (7) were isolated from the ethyl acetate extract of barks of Zygogynum pancheri subsp. arrhantum (Winteraceae). The structures of these molecules were assigned predominantly based on spectral data. The structure of compound 8 was confirmed by X-ray crystallographic analysis. Compounds 2 and 3 exhibited significant antioxidant activity, whereas compounds 1 and 4–7 showed significant α-amylase inhibitory activity.     

A novel spinosin derivative from Semen Ziziphi Spinosae

A novel spinosin derivative, 6?-(4?′-O-β-d-glucopyranosyl)-vanilloyl spinosin (1) was isolated from the methanol extract of Semen Ziziphi Spinosae, together with five known flavonoids, swertish (2), spinosin (3), 6?-feruloylspinosin (4), isospinosin (5) and kaempferol 3-O-α-l-rhamnopyranosyl-(1 → 2)-O-[O-α-l-rhamnopyranosyl-(1 → 6)]-β-d-glucopyranoside (6), and two alkanoids, zizyphusine (7) and 6-(2′,3′-dihydroxyl-4′-hydroxymethyl-tetrahydro-furan-1′-yl)-cyclopentene[c]pyrrole-1,3-diol (8). The structure of compound 1 was elucidated by spectroscopic methods including UV, IR, ESI-TOF-MS, 1D, and 2D NMR techniques.     

A novel chloro-substituted pentenamide from the fruiting bodies of Amanita virgineoides

One unusual chloro-substituted pentenamide, (3R)-4-chloro-3-hydroxy-4-pentenamide (1), together with 11 known compounds (2–12) were isolated from the fruiting bodies of Amanita virgineoides. The structure of 1 including the absolute configuration was characterized by extensive spectroscopic analyses and quantum calculation. Compound 1 displayed no obvious activity against herpes simplex virus (HSV), human enterovirus 71 (EV71) or coxsackievirus B3 (CVB3).     

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 compounds from the dry leaves of Pleioblastus amarus (Keng) keng f.

Two new compounds, xylitol 1-O-(6′-O-p-hydroxylbenzoyl)-glucopyranoside (1) and bambulignan B (2), together with three known ones gastrodin (3), glucovanillin (4), and rel-(7S,7′R,8R,8′S)-4,4′-dihydroxy-3,3′,5,5′-tetramethoxy-7,7′-epoxyligna-9,9′-diol-9(or)9′-O-β-glucopyranoside (5), were isolated from the 95% EtOH extract of the dry leaves of Pleioblastus amarus (Keng) keng f. Their structures were determined by UV, IR, HR-ESI-MS, CD, and 1D and 2D NMR data analyses as well as GC experiments.     

Three new steroidal saponins from Fritillaria pallidiflora

Three new steroidal saponins, pallidiflosides A (1), B (2), and C (3), have been isolated from the dry bulbs of Fritillaria pallidiflora Schrenk. Their structures were elucidated as 26-O-β-d-glucopyranosyl-(25R)-furost-5,20(22)-dien-3β,26-diol-3-O-β-d-xylopyranosyl(1 → 4)-[α-l-rhamnopyranosyl(1 → 2)]-β-d-glucopyranoside (1); 26-O-β-d-glucopyranosyl-3β,26-dihydroxyl-20,22-seco-25(R)-furost-5-en-20,22-dione-3-O-α-l-rhamnopyranosyl(1 → 2)-β-d-glucopyranoside (2); and (25R)-spirost-5-ene-3β,17α-diol-3-O-β-d-glucopyranosyl(1 → 4)-β-d-galactopyranoside (3) by spectroscopic techniques and chemical means.     

Two flavonoid glycosides and a phenylpropanoid glucose ester from the leaves of Sterculia foetida

Two new flavonoid glycosides, hypolaetin 4′-methyl ether 8-O-β-d-glucuronide 2″-sulfate (1) and hypolaetin 4′-methyl ether 3′-O-β-d-glucoside (2), and a new phenylpropanoid glucose ester, 1,6-diferuloyl glucose (3), were isolated from the leaves of Sterculia foetida L. Their structures were elucidated by spectroscopic analysis and chemical evidence.