Biologically active <Emphasis Type="Italic">C</Emphasis>-alkylated flavonoids from <Emphasis Type="Italic">Dodonaea viscosa</Emphasis>

A new C-alkylated flavonoid (5,7-dihydroxy-3′-(4″-acetoxy-3″-methylbutyl)-3,6,4′-trimethoxyflavone (1), along with two known C-alkylated flavonoids (5,7-dihydroxy-3′-(3-hydroxymethylbutyl)-3,6,4′-trimethoxyflavone (2), 5,7,4′-trihydroxy-3′-(3-hyroxymethylbutyl)-3,6-dimethoxyflavone (3) and two new source C-alkylated flavonoids (5,7-dihydroxy-3′-(2-hydroxy-3-methyl-3-butenyl)-3,6,4′-trimethoxyflavone (4), 5,7,4′-trihydroxy-3,6-dimethoxy-3′-isoprenyl-flavone (5) were isolated from the aerial parts of Dodonaea viscosa. The structures of all compounds were established on the basis of 1D and 2D NMR spectroscopy and mass spectrometry. The isolated compounds were evaluated for their inhibitory effect on urease and α-chymotrypsin enzyme. All the compounds (1–5) exhibited mild inhibition against urease but remained recessive in case of α-chymotrypsin.     

Iridoid glucoside, (3<Emphasis Type="Italic">R</Emphasis>)-oct-1-en-3-ol glycosides,and phenylethanoid from the aerial parts of <Emphasis Type="Italic">Caryopteris incana</Emphasis>

Eleven compounds of interest were isolated from the aerial parts of Caryopteris incana, specifically a new acyl derivative (3) of 8-O-acetylharpagide, two new (3R)-oct-1-en-3-ol glycosides (5, 6), and 6-O-caffeoylphlinoside A (11) along with seven known compounds, 8-O-acetylharpagide (1), 6′-O-p-coumaroyl-8-O-acetylharpagide (2), (3R)-oct-1-en-3-ol (matsutake alcohol) O-α-l-arabinopyranosyl-(1″ → 6′)-O-β-d-glucopyranoside (4), apigenin 7-O-neohesperidinoside (7), 6′-O-caffeoylarbutin (8), and two phenylethanoids, leucosceptoside A (9) and phlinoside A (10). This paper deals with structural elucidation of the new compounds.     

A new prenylated dihydrochalcone from the leaves of <Emphasis Type="Italic">Artocarpus lowii</Emphasis>

A new prenylated dihydrochalcone, 2′,4′-dihydroxy-4-methoxy-3′-prenyldihydrochalcone (1), along with two known compounds, 2′,4′,4-trihydroxy-3′-prenylchalcone (2) and 2′,4-dihydroxy-3′,4′-(2,2-dimethylchromene)chalcone (3) were isolated from the leaves of Artocarpus lowii. The structures of 1–3 were elucidated by spectroscopic methods and by comparison with data reported in the literature. Compounds 1–3 showed strong free radical scavenging activity towards 2,2-diphenyl-1-picrylhydrazyl (DPPH) measured by electron spin resonance (ESR) spectrometry.     

A new furofuran lignan from <Emphasis Type="Italic">Isodon japonicus</Emphasis>

A new sesamin type furofuran lignan, (−)-sesamin-2,2′-diol (1), along with two known flavonoids (2 and 3) and three phenolic compounds (4–6) were isolated from the aerial parts of Isodon japonicus. The structures of these compounds were determined by analysis of spectroscopic data (1D-, 2D-NMR, HRMS and CD) and by comparison of the data with those of related metabolites.     

Potential anthelmintics: polyphenols from the tea plant <Emphasis Type="Italic">Camellia sinensis</Emphasis> L. are lethally toxic to <Emphasis Type="Italic">Caenorhabditis elegans</Emphasis>

A novel gallate of tannin, (−)-epigallocatechin-(2β→O→7′,4β→8′)-epicatechin-3′-O-gallate (8), together with (−)-epicatechin-3-O-gallate (4), (−)-epigallocatechin (5), (−)-epigallocatechin-3-O-gallate (6), and (+)-gallocatechin-(4α→8′)-epigallocatechin (7), were isolated from the tea plant Camellia sinensis (L.) O. Kuntze var. sinensis (cv., Yabukita). The structure of 8, including stereochemistry, was elucidated by spectroscopic methods and hydrolysis. The compounds, along with commercially available pyrogallol (1), (+)-catechin (2), and (−)-epicatechin (3), were examined for toxicity towards egg-bearing adults of Caenorhabditis elegans. The anthelmintic mebendazole (9) was used as a positive control. Neither 2 nor 3 were toxic but the other compounds were toxic in the descending order 8, 7 ≈ 6, 9, 4, 5, 1. The LC₅₀ (96 h) values of 8 and 9 were evaluated as 49 and 334 μmol L⁻¹, respectively. These data show that many green tea polyphenols may be potential anthelmintics.     

A new phenolic glucoside from an Uzbek medicinal plant, Origanum tyttanthum

A new phenolic glucoside was isolated from the aerial parts of Origanum tyttanthum, an Uzbek medicinal plant, together with 12 known compounds. The structure of the new compound was elucidated as 4-O-β-d-glucopyranosylbenzyl-3′-hydroxyl-4′-methoxybenzoate (1) based on the spectral and chemical evidence.     

A new ceramide from <Emphasis Type="Italic">Ramaria botrytis</Emphasis> (Pers.) Ricken

A new ceramide, (2S,2′R,3R,4E,8E)-N-2′-hydroxyoctadecanoyl-2-amino-9-methyl-4,8-heptadecadiene-1,3-diol (1), was isolated together with four known sterols, 5α,6α-epoxy-3β-hydroxy-(22E)-ergosta-8(14),22-dien-7-one (2), ergosterol peroxide (3), cerevisterol (4) and 9α-hydroxycerevisterol (5), from the fruiting bodies of Ramaria botrytis (Pers.) Ricken (Ramariaceae). The structure of the new compound was elucidated based on spectral data.     

Immunosuppressive effects of new cyclolanostane triterpene diglycosides from the aerial part of <Emphasis Type="Italic">Cimicifuga foetida</Emphasis>

Two new cyclolanostane diglycosides, cimifoetiside A (1) and cimifoetiside B (2), were isolated from an 80% ethanolic extract of the aerial part of Cimicifuga foetida L. (Ranuculaceae). Using spectral data and chemical analysis, the structures of 1 and 2 were identified as (23R, 24S) cimicigenol 3-O-β-D-glucopyranosyl-(1″→3′)-β-D-xylopyranoside and (23R, 24S) cimicigenol 3-O-β-D-glucopyranosyl-(1″→2′)-β-D-xylopyranoside, respectively. The in vitro immunosuppressive effects of the two new compounds 1 and 2, as well as four other known cyclolanostane saponins 3–6 on T cells were evaluated. All the agents tested effectively inhibited the proliferation of murine splenocytes induced by Concanavalin A (ConA), with IC₅₀ values ranging from 12.7 nM to 33.3 nM.     

Flavonoids from the aerial parts ofLonicera japonica

Seven flavonoids were isolated from the aerial parts ofLinocera japonica. Their structures were characterized as hydnocarpin1, quercetin2, ochnaflavone3, ochnaflavone 4′-O-methylether4, astragalin5, isoquercitrin6, and rhoifolin7 by chemical and spectroscopic evidences.     

Four new glucosides from the aerial parts of Mediasia macrophylla

As part of our chemical studies on the medical plants in Uzbekistan aimed at searching for new drug leads, we have examined the aerial parts of Mediasia macrophylla. This has resulted in the isolation of four new glucosides, together with 30 known compounds. The structures of new compounds were elucidated as (1′S)-(4-hydroxyphenyl) ethane-1′,2′-diol 2′-O-β-glucopyranoside (1), 3-(4′-methoxyphenyl)-propanol 1-O-β-glucopyranoside (2), 2-methoxy-3-hydroxy-5-(E)-propenyl-phenol 1-O-β-glucopyranoside (3), 1-O-angeloyl-β-glucopyranose (4), on the basis of spectral analysis.     

Phenolic constituents of <Emphasis Type="Italic">Acorus gramineus</Emphasis>

The purification of a MeOH extract from the rhizome of Acorus gramineus (Araceae) using column chromatography furnished two new stereoisomers of phenylpropanoid, acoraminol A (1) and acoraimol B (2). It also furnished 17 known phenolic compounds, β-asarone (3), asaraldehyde (4), isoacoramone (5), propioveratrone (6), (1′R,2′S)-1′,2′-dihydroxyasarone (7), (1′S,2′S)-1′,2′-dihydroxyasarone (8), 3′,4′-dimethoxycinnamyl alcohol (9), 3′,4′,5′-trimethoxycinnamyl alcohol (10), kaempferol 3-methyl ether (11), 2-[4-(3-hydroxypropyl)-2-methoxyphenoxy]-1,3-propanediol (12), hydroxytyrosol (13), tyrosol (14), (2S,5S)-diveratryl-(3R,4S)-dimethyltetrahydrofuran (15), (7S,8R)-dihydrodehydrodiconiferyl alcohol (16), 7S,8S-threo-4,7,9,9′-tetrahydroxy-3,3′-dimethoxy-8-O-4′-neolignan (17), 7S,8R-erythro-4,7,9,9′-tetrahydroxy-3,3′-dimethoxy-8-O-4′-neolignan (18), and dihydroyashsbushiketol (19). The structures of the new compounds were elucidated by analysis of spectroscopic data including 1D and 2D NMR data. The absolute configurations of 1 and 2 were determined using the convenient Mosher ester procedure. Compounds 5–19 were isolated for the first time from this plant source. The isolated compounds were tested for cytotoxicity against four human tumor cell lines in vitro using a Sulforhodamine B (SRB) bioassay.     

A new phenolic glycoside syringate from the bark of <Emphasis Type="Italic">Juglans mandshurica</Emphasis> MAXIM. var. <Emphasis Type="Italic">sieboldiana</Emphasis> MAKINO

A new phenolic glycoside syringate, 4′-hydroxy-2′,6′-dimethoxyphenol 1-O-β-d-(6-O-syringoyl) glucopyranoside (1), together with two known ones, 2′-hydroxy-4′-methoxyphenol 1-O-β-d-(6-O-syringoyl) glucopyranoside (2) and 4′-hydroxy-2′-methoxyphenol 1-O-β-d-(6-O-syringoyl) glucopyranoside (3), were isolated from the bark of Juglans mandshurica MAXIM. var. sieboldiana MAKINO. Their structures were established on the basis of spectral and chemical data.     

Two new phenolic glycosides from <Emphasis Type="Italic">Syringa reticulata</Emphasis>

Two new phenolic glycosides—3′-O-β-d-glucopyranosysalidroside (1) and cis-echinacoside (2)—together with four known ones—forsythoside B (3), decaffeoylacteoside (4), osmanthuside F (5) and (−)-olivil-4′-O-β-d-glucopyranoside (6)—were isolated from the leaves of Syringa reticulata. Their structures were established on the basis of spectral and chemical data.     

Two new dihydrofuranoisoflavanones from the leaves of <Emphasis Type="Italic">Lespedeza maximowiczi</Emphasis> and their inhibitory effect on the formation of advanced glycation end products

Two new dihydrofuranoisoflavanones, 2′,4′,5-trihydroxy-[5″-(1,2-dihydroxy-1-methylethyl)-dihydrofurano(2″,3″:7,8)]-(3S)-isoflavanone (1) and 2′, 4′, 5-trihydroxy-[5″-(1,2-dihydroxy-1-methylethyl)-dihydrofurano(2″,3″:7,8)]-(3R)-isoflavanone (2) as well as one already-known compound, (+)-catechin (3), were isolated from an n-BuOH soluble fraction from the leaves of Lespedeza maximowiczi. Spectroscopic data was used to elucidate the structures of compounds 1 and 2. All of the isolates were evaluated in vitro for their inhibitory activity on the formation of advanced glycation end products (AGEs). Among these, compounds 1, 2, and 3 exhibited inhibitory activity against AGEs formation with IC₅₀ values of 20.6, 18.4, and 5.6 μM, respectively.     

Monoterpene glycoside and flavonoids from <Emphasis Type="Italic">Blumea lacera</Emphasis>

The dichloromethane extract of air-dried leaves of Blumea lacera (Asteraceae) afforded α-pinene-7β-O-β-d-2,6-diacetylglucopyranoside (1), 5,4′-dihydroxy-6,7,3′-trimethoxyflavone (2), and 3,5,4′-trihydroxy-6,7,3′-trimethoxyflavone (3). Compounds 1–3 showed moderate activity against Candida albicans, low activity against Trichophyton mentagrophytes, and were inactive against Aspergillus niger. Compounds 1 and 3 indicated low activity against Escherichia coli, Pseudomonas aeruginosa, and Staphylococcus aureus and were inactive against Bacillus subtilis, while 2 was inactive against all four bacteria tested.     

Two new neolignan glycosides from leaves of <Emphasis Type="Italic">Osmanthus heterophyllus</Emphasis>

Two new neolignan glycosides, (7R, 8R)-threo-guaiacylglycerol-8-O-4′-sinapyl ether 7-O-β-d-glucopyranoside (1) and (7S, 8R)-5-methoxydehydrodiconiferyl alcohol 4-O-β-d-glucopyranoside (2), and four known ones (3–6), were isolated from the leaves of Osmanthus heterophyllus. The structures of compounds 1–6 were established on the basis of spectral and chemical data.     

New anthracene glycosides from <Emphasis Type="Italic">Rhodomyrtus tomentosa</Emphasis> stimulate osteoblastic differentiation of MC3T3-E1 cells

Two new anthracene glycosides (1, 2) were isolated from aerial parts of Rhodomyrtus tomentosa, along with three known compounds (3–5). The structures of two new compounds were established to be 4,8,9,10-tetrahydroxy-2,3,7-trimethoxyanthracene-6-O-β-D-glucopyranoside (1) and 2,4,7,8,9,10-hexahydroxy-3-methoxyanthracene-6-O-α-L-rhamnopyranoside (2) based on spectroscopic and chemical methods. Among them, compound 1, 2, and 5 significantly (P<0.05) increased the alkaline phosphatase activity, collagen synthesis, and mineralization of the nodules of MC3T3-E1 osteoblastic cells compared to those of the control, respectively.     

Phenylpropanoid glycosides from <Emphasis Type="Italic">Heterosmilax erythrantha</Emphasis> and their antioxidant activity

By various chromatographic methods, one new phenylpropanoid glycoside, heterosmilaside (1), two known phenylpropanoid glycosides, helonioside B (2), and 2′,6′-diacetyl-3,6-diferuloyl sucrose (3), and three known flavonoids, isoquercetin (4), quercetin-3-O-β-D-glucuronopyranoside (5), and quercetin-3-O-(2″-α-L-rhamnopyranosyl)-β-D-glucuronopyranoside (6) were isolated from the methanolic extract of the aerial part of Heterosmilax erythrantha Baill. Their structures were elucidated on the basis of spectroscopic analyses. All the isolated compounds were tested for antioxidant activity in the 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging assay. Among them, compounds 5 and 6 showed significant antioxidant activity with SC₅₀ values of 3.7 and 6.5 μg/mL, respectively.     

Chemical and biologically active constituents of <Emphasis Type="Italic">Pteris multifida</Emphasis>

A new compound, 4-caffeoyl quinic acid 5-O-methyl ether (2), together with 12 known compounds—identified as (2R,3R)-pterosin L 3-O-β-d-glucopyrannoside (3), β-sitosterol β-d-glucopyranoside (4), apigenin 7-Ο-β-d-glucopyranoside (5), luteolin 7-Ο-β-d-glucopyranoside (6), sucrose (7), caffeic acid (8), pterosin C 3-Ο-β-d-glucopyranoside (9), pteroside C (10), 4,5-dicaffeoyl quinic acid (11), pteroside A (12), wallichoside (13) and (2S)-5,7,3′,5′-tetrahydroxyflavanone (14)—were isolated from Pteris multifida. The structure of the new compound was determined by means of physical, chemical and spectroscopic evidence. Compounds 5 and 6 were the main constituents of the plant, with yields of 0.19% and 0.16%, respectively. The cytotoxic activities of 2, 3, and 9–13 were evaluated against a human cell line (KB cells). Among the isolated compounds, pterosin C 3-Ο-β-d-glucopyrannoside (9) and 4,5-dicaffeoylquinic acid (11) showed a significant selective cytotoxicity (IC₅₀ 2.35 and 5.38, respectively), while moderate activity was observed for compound 2 (IC₅₀ 12.3). The chemosystematics of Pteris species is also discussed.     

New isoflavone glycosides from <Emphasis Type="Italic">Iris spuria</Emphasis> L. (Calizona) cultivated in Egypt

Two new isoflavone glycosides, tectorigenin 7-O-β-d-glucopyranoside-4′-O-[β-d-glucopyranosyl-(1″″ → 6′′′)-β-d-glucopyranoside] (1) and iristectorigenin B 4′-O-[β-d-glucopyranosyl-(1′′′ → 6″)-β-d-glucopyranoside] (2), together with 11 known compounds, including six isoflavones, tectorigenin 7-O-β-d-glucopyranoside-4′-O-β-d-glucopyranoside (3), tectorigenin 4′-O-[β-d-glucopyranosyl-(1′′′ → 6″)-β-d-glucopyranoside] (4), tectorigenin 7-O-β-d-glucopyranoside (5), genistein 7-O-β-d-glucopyranoside (6), tectorigenin 4′-O-β-d-glucopyranoside (7), and tectorigenin (8); two phenolic acid glycosides, vanillic acid 4-O-β-d-glucopyranoside (9) and glucosyringic acid (10); a phenylpropanoid glycoside, E-coniferin (11); an auronol derivative, maesopsin 6-O-β-d-glucopyranoside (12); and a pyrrole derivative, 4-(2-formyl-5-hydroxymethylpyrrol-1-yl) butyric acid (13), were isolated from fresh Iris spuria (Calizona) rhizomes. The structures of these compounds were established on the basis of spectroscopic and chemical evidence. Inhibitory effects on the activation of Epstein–Barr virus early antigen were examined for compounds 1–8 and 12.