Total synthesis of syringalide B, a phenylpropanoid glycoside

The first total synthesis of syringalide B, 2-(4-hydroxyphenyl)ethyl 4-O-[(E)-feruloyl]-beta-D-glucopyranoside, is described. The hydroxyl groups were protected with allyloxycarbonyl (Aoc) and allyl groups, which successfully prevent the migration of the feruloyl group during the deblocking procedure.     

Total synthesis of phenylpropanoid glycosides, grayanoside A and syringalide B, through a common intermediate

Phenylpropanoid glycosides are known as bioactive natural products. Two of them, grayanoside A (1) and syringalide B (2), were synthesized through a common intermediate, using benzyl as temporary protecting group following a shorter route.     

New phenylpropanoid allopyranosides from the rhizomes of Cimicifuga dahurica

Five new phenylpropanoid allopyranosides (1–5), along with five known compounds (6–10) were isolated from the rhizomes of Cimicifuga dahurica. Their structures were established by means of spectroscopic analyses and chemical methods, as well as comparison with literatures. The anti-inflammatory activities of all isolates were evaluated. Compounds 6, 9 and 10 exhibited inhibitory effects on PGE₂ production in LPS stimulated RAW 264.7 macrophages with IC₅₀ values of 19.72, 6.33 and 39.90 µM, respectively.     

Trichotomoside: a new antioxidative phenylpropanoid glycoside from Clerodendron trichotomum

The structure and antioxidant properties of a new natural glycoside, trichotomoside (1), isolated from Clerodendron trichotomum, were investigated. Trichotomoside was identified as 2-(3-hydroxy-4-methoxyphenyl)ethyl 3-O-(2,3-di-O-acetyl-alpha-L-rhamnopyranosyl)-4-O-[(2E)-3-(3-hydroxy-4-methoxyphenyl)prop-2-enoyl]-beta-D-glucopyranoside. The compound was active towards intracellular reactive oxygen species (ROS) and exhibited DPPH-radical-scavenging effects. The radical-scavenging activity of 1 was found to protect the viability of Chinese hamster lung fibroblasts (V79-4 cells) exposed to H2O2 and gamma-irradiation.     

Four new phenylpropanoid glycosides from Clausena dunniana var. robustaand their antiinflammatory activities

Four new phenylpropanoid glycosides, clausenaglycosides A–D (1–4), along with fourteen known compounds (5–18) were isolated from the leaves and twigs of Clausena dunniana var. robusta. The structures of the isolated compounds were determined by a combination of 1D and 2D NMR, MS, and CD spectroscopic data. The NF-κB inhibitory activity was evaluated in HeLa cells. Compound 17 displayed a moderate inhibition against NF-κB activation.     

Isomartynoside,a phenylpropanoid glycoside from Galeopsis pubescens

The structure of isomartynoside, a new phenylpropanoid glycoside, isolated along with the known martynoside from Galeopsis pubescens, has been elucidated on the basis of chemical and spectral data as 3-hydroxy-4-methoxy-β-phenylethoxy-O-α-L-rhamnopyranosyl-(1 → 3)-6-O-feruloyl-β-D-glucopyranoside.     

Brandioside, a phenylpropanoid glycoside from Brandisia hancei.

A new phenylpropanoid glycoside, brandioside, was isolated from Brandisia hancei. Its structure, [beta-(3',4'-dihydroxylphenyl)-ethyl]-(2-O-acetyl)-(3,6-O-di-alpha -L-rhamnopyranosyl)-(4-O-caffeoyl)-beta-D-glucopyranoside, was established by chemical and spectroscopic methods.     

Antioxidant phenylpropanoid glycosides from the leaves of Wasabia japonica

From the MeOH extract of the leaves of W. japonica, seven phenylpropanoid gentiobiosides (1-7) were isolated along with eight known phenylpropanoids (8-15). Structures of 1-7 were determined based on spectroscopic data and chemical evidence. The activity of compounds 1-15 to scavenge superoxide anion radicals was investigated using an electron spin resonance (ESR) method.     

Synthesis of two bidesmosidic ursolic acid saponins bearing a 2,3-branched trisaccharide residue

The focus of this work was on the synthesis of two bidesmosidic ursolic acid saponins bearing a 2,3-branched trisaccharide residue. Therefore, 3-O-{[beta-D-glucopyranosyl-(1-->2)]-[alpha-L-arabinopyranosyl-(1-->3)]-alpha-L-arabinopyranosyl}ursolic acid-28-O-[beta-D-glucopyranosyl] ester 1 was concisely synthesized by two strategies in 22% and 41% overall yield, respectively, and another congener 3-O-{[beta-D-xylopyranosyl-(1-->2)]-[beta-D-glucopyranosyl-(1-->3)]-alpha-L-arabinopyranosyl}ursolic acid-28-O-[beta-D-glucopyranosyl] ester 2 was also efficiently prepared in 81% overall yield. The (1)H NMR and (13)C NMR signals of saponin 2 are all consistent with those reported for the natural product.     

Isoangoroside C, a phenylpropanoid glycoside from Scrophularia scorodonia roots

A new phenylpropanoid glycoside isoangoroside C was isolated from the roots of Scrophularia scorodonia. Its structure was determined on the basis of spectral data as: 3-hydroxy-4-methoxy-beta-phenylethoxy-O-alpha-L-arabinopyranosy l-(1-->6)alpha L-rhamnopyranosyl-(1-->3)-4-O-Z-feruloyl-beta-D-glucopyranoside. Additionally, one known phenylpropanoid, angoroside C, and five known iridoid glycosides, harpagoside, bartsioside, 8-O-acetyl-harpagide, aucuboside and harpagide were isolated and identified.     

Antioxidant phenylpropanoid glycosides from Smilax bracteata

From the ethanolic extract of Smilax bracteata, six phenylpropanoid glycosides, smilasides G-L (1-6), along with four known phenylpropanoid compounds, helonioside A, helonioside B, smilaside E, and (1-p-O-coumaroyl-6-O-feruroyl)-beta-d-fructofuranosyl-alpha-d-glucopyranoside, and fourteen known phenolic compounds were isolated. Their structures were elucidated on the basis of spectroscopic analyses. Moreover, 1-6 exhibited moderate scavenging activities against DPPH radicals.     

Structures and biological evaluation of phenylpropanoid derivatives from Murraya koenigii

Four new phenylpropanoid derivatives (1–4), together with eleven known analogues (5–15) were isolated and identified by comparison with their references and extensive spectroscopic methods from Murraya koenigii for the first time. Compounds (1–15) were assayed for their inhibitory activities by measuring IL-6-induced STAT3 promoter activities in HepG2 cells, and found compounds 1, 2, 6, and 15 showed inhibitory effects with IC₅₀ values of 11.5, 18.7, 8.9, and 22.7 μM, respectively. The inhibitory activities of compounds (1–15) were screened against NO production in lipopolysaccharide (LPS)-induced RAW264.7 macrophage cells, and found compounds 3, 4, 9, 11, and 14 exhibited inhibitions against LPS-induced NO production in RAW264.7 macrophages, with IC₅₀ values of 32.7, 7.9, 42.1, 58.9, and 62.4 μM, respectively.     

Synthesis of Lewis X trisaccharide analogues in which glucose and rhamnose replace N-acetylglucosamine and fucose,respectively

Two analogues of the Le(x) trisaccharide, alpha-L-Fucp-(1-->3)-[beta-D-Galp-(1-->4)]-D-Glcp were synthesized as allyl glycosides. In these derivatives either only the N-acetylglucosamine is replaced by glucose or both the N-acetylglucosamine and the fucosyl residue are replaced by glucose and rhamnose, respectively. Our synthetic scheme used armed beta-thiophenyl fuco- and rhamnoside glycosyl donors that were prepared anomerically pure from the corresponding alpha-glycosyl bromides. The protecting groups were chosen to allow access to the fully deprotected trisaccharides without reduction of the allyl glycosidic group. These analogues will be used as soluble antigens in binding experiments with anti-Le(x) antibodies and can also be conjugated to a carrier protein and used as immunogens. In the course of this synthetic work, we also describe the use of reversed-phase HPLC to purify key protected trisaccharide intermediates prior to their deprotection.     

4‴-O-acetylsarotanoside,a novel flavanone glycoside from Nierembergia hippomanica

A new flavanone glycoside was isolated from the aerial parts of Nierembergia hippomanica and identified as the 4?-acetate of pinocembrin 7-neohesperidoside.     

Unusual new phenylethanoid and phenylpropanoid diglycosides from the leaves of Chloranthus spicatus (Thunb.) Makino

Chloranthus spicatus (Thunb.) Makino (Chloranthaceae) has been used to treat aches, trauma, and bleeding in Traditional Chinese Medicine. Phytochemical investigation of the leaves of this plant led to the isolation an unusual new phenylethanoid diglycoside, spicaoside (1), and a new phenylpropanoid diglycoside, 1-allyl-3-methoxy-4- [apiofuranosyl(1 ⿿ 2)-glucopyranosyloxybenzene] (2), along with two known sesquiterpenoid glycosides, chloranoside A (3) and chloranthalactone E 8-O-β-d-glucopyranoside (4). Their structures were established by spectroscopic means. New compounds 1 and 2 showed moderate tyrosinase inhibitory activities with the IC₅₀ value of 15.4 μM and 29.1 μM. This study represents the first report of glycoside from C. spicatus.     

抗肿瘤药物帕玛度胺类似物的合成

目的：设计并合成抗肿瘤药物帕玛度胺的3位N取代的新型类似物。方法：从3-硝基邻苯二甲酸（2）和N-（叔丁氧羰基）．L-谷氨酰胺（4）出发,经过六步反应得到目标化合物。3-硝基邻苯二甲酸（2）经脱水制得3-硝基邻苯二甲酸酐（3）。用N-（叔丁氧羰基）-L-谷氨酰胺（4）经闭环、脱保护制得3-氨基-2,6-哌啶二酮三氟乙酸盐（6）。4与6经缩合、钯碳催化氢化制得免疫调节剂Pomalidomide（8）,（8）经过酰化得到3-乙酰氨基-N-（2,6-二氧代-3-哌啶基）邻苯二甲酰亚胺（1）。以（4）计总收率约34．9％。结果：得到3-乙酰氨基-N-（2,6-二氧代-3-哌啶基）-邻苯二甲酰亚胺（1）,应用于细胞活性测试。结论：改进了帕玛度胺的合成工艺,得到了3位N乙酰化的新型帕玛度胺类似物（1）,初步研究显示（1）的生物活性与帕玛度胺接近。     

A new phenylpropanoid ester from the roots of Anthriscus sylvestris and its chemotaxonomic significance

A new phenylpropanoid ester, anthriscusin I (1), along with six known compounds (2–7) were isolated from the Anthriscus sylvestris (L.) Hoffm roots. The new compound structure was elucidated via spectroscopic analyses, while the known compounds were identified via comparison literature. The chemotaxonomic significance of these compounds was discussed.     

Effects of verbascoside,a phenylpropanoid glycoside from lemon verbena,on phospholipid model membranes

Phenylpropanoid glycosides are water-soluble compounds widely distributed, most of them deriving from medicinal herbs. Among them, verbascoside or acteoside has exhibited a wide biological activity, being free radical scavenging the most representative one. Moreover, antitumor, antimicrobial, anti-inflammatory, anti-thrombotic and wound healing properties have been previously described. Herein, the interaction of verbascoside with phospholipid membranes has been studied by means of differential scanning calorimetry, fluorescence anisotropy and dynamic light scattering. Verbascoside showed stronger affinity for negatively charged membranes composed of phosphatidylglycerol (PG) than for phosphatidylcholine (PC) membranes. This compound promoted phase separation of lipid domains in PC membranes and formed a stable lipid complex with and approximate phospholipid/verbascoside ratio of 4:1. Despite its hydrophilic character, verbascoside's caffeoyl moiety was located deep into the hydrophobic core of PC membranes and was almost inaccessible to spin probes located at different depths in PG membranes. This compound affected the ionization behavior of the PG phosphate group and most likely interacted with the vesicles surface. The presence of verbascoside decreased the particle size in PG unilamellar vesicles through the increase of the phospholipid head group area. A localization of verbascoside filling the upper region of PG bilayers close to the phospholipid/water interface is proposed. These effects on membranes may help to understand the mechanism of the biological activity of verbascoside and other similar phenylpropanoid glycosides.