Four new iridoid glucosides from Ajuga reptans

Four new iridoid glucosides were isolated from the whole plant of Ajuga reptans L. (Labiatae) along with four known iridoid glucosides, one known diterpenoid glycoside, one known aliphatic alcohol glycoside, and three known ecdysteroids. Their chemical structures were determined on the basis of spectroscopic data and chemical evidence. The diterpenoid glycoside exhibited 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical and H?O? scavenging activities.     

Two new iridoid glycosides from the Tibetan folk medicine Swertia franchetiana

Two new iridoid glycosides designated as senburiside III (2) and senburiside IV (3), together with one known iridoid glycoside senburiside I (1) and three known secoiridoid glucosides swertiamarin (4), gentiopicroside (5) and sweroside (6), were isolated from the whole plant of Swertia franchetiana. The structures of the two new compounds were elucidated by spectroscopic methods.     

Iridoid glycosides from Globularia davisiana

From the ethanolic extract of the aerial parts of Globularia davisiana, a new iridoid glycoside, davisioside (1), was isolated. Davisioside (1) comprises a rare iridoid aglycone structure with a saturated double bond between C-3 and C-4. Nine known iridoid glycosides, asperuloside (2), alpinoside (3), geniposide (4), globularin (5), globularicisin (6), 10-O-benzoylcatalpol (7), lytanthosalin (8), melampyroside (9), agnuside (10), and three known phenylethanoid glycosides, verbascoside, isoacteoside and leucosceptoside A were also isolated and characterized. The structures of the isolates were established by spectroscopic methods (one-dimensional (1D)- and two-dimensional (2D)-NMR, MS).     

Monoterpene constituents from Cistanche tubulosa--chemical structures of kankanosides A-E and kankanol-

Four new iridoid glycosides, kankanosides A (1), B (2), C (3), and D (4), a chlorinated iridoid, kankanol (5), and an acyclic monoterpene glycoside, kankanoside E (6), were isolated from the methanolic extract of dried stems of Cistanche tubulosa (SCHRENK) R. WIGHT (Orobanchaceae) together with 16 known compounds. The structures of these new compounds (1-6) were determined on the basis of the chemical and physicochemical evidence.     

A New Iridoid Glycoside and a New Iridoid from Pedicularis kansuensis f. aibiflora

A new iridoid glycoside 1 and a new iridoid 2 were isolated from the whole plant ofPedicularis kansuensis f. albiflora. Their structures were elucidated by spectroscopic methods.     

A New Iridoid Glycoside and a New Iridoid from Pedicularis kansuensis f. albiflora

A new iridoid glycoside 1 and a new iridoid 2 were isolated from the whole plant of Pedicularis kansuensis f. albiflora. Their structures were elucidated by spectroscopie methods.     

Iridoid Glycosides and Phenolic Compounds from the Flowers of Vitex agnus‐castus

A new and rare type of iridoid glycoside, agnusoside ( 1 ), a new caffeoylquinic acid derivative, castusic acid ( 2 ), and a new sugar ester, 1,2‐di‐(4‐hydroxybenzoyl)‐β‐glucopyranose ( 3 ), along with ten known compounds belonging to iridoid glycosides (agnuside, trans‐eurostoside), caffeoylquinic acid derivatives (chlorogenic acid and isochlorogenic acid A), flavonoids (isoorientin, isovitexin, kaempferol 3‐O‐sophoroside, luteolin 6‐C‐(2′′‐O‐trans‐caffeoyl)glucopyranoside, and simple phenolic acids (4‐hydroxybenzoic acid, 3,4‐dihydroxybenzoic acid), chemical classes were isolated from the flowers of Vitex agnus‐castus. The structures of the isolates were established by extensive 1D‐ and 2D‐NMR spectroscopic analysis as well as HR‐ESI‐MS. Agnusoside ( 1 ) represents an unusual type of iridoid glycoside with its 6‐keto C(4) nonsubstituted aglycone.     

Lavandulifolioside B: a new phenylethanoid glycoside from the aerial parts of Stachys lavandulifolia Vahl

Reversed-phase preparative HPLC analyses of the methanol extract of the aerial parts of Stachys lavandulifolia afforded a new phenylethanoid glycoside, 4,3',4'-trimethoxy-lavandulifolioside A, named lavandulifolioside B, together with three other known phenylethanoid glycosides, lavandulifolioside A, verbascoside and leucosceptoside A, and an iridoid glycoside 5-O-β-allopyranosyloxy-aucubin (5-O-β-allopyranosyl-monomelittoside). While the structures of the known compounds, except the iridoid glycoside, were established by direct comparison of their spectroscopic data with respective literature data, lavandulifolioside B and 5-O-β-allopyranosyloxy-aucubin were identified comprehensively by extensive 1D and 2D NMR analyses. The distribution of the isolated compounds within the genus Stachys has been discussed.     

A novel iridoid glycoside from the aerial parts of the Tunisian Prasium majus

Repeated fractionation of the acetylated methanol extract of Prasium majus afforded acetylated derivatives of a new iridoid glycoside hamighriprasin (1), myoporoside (2), beta-D-glycopyranose (3) and saccharose (4). The structures of 1 and 2 were established by interpretation of 1D and 2D NMR data of their corresponding acetylated derivatives and by comparison with the literature.     

A new iridoid glycoside with nerve growth factor-potentiating activity,gelsemiol 6'-trans-caffeoyl-1-glucoside,from Verbena littoralis

A new iridoid glycoside, gelsemiol 6'-trans-caffeoyl-1-glucoside (1), was isolated from Verbena littoralis, together with four known phenylethanoid glycosides, acteoside (2), 2'-acetylacteoside (3), jionoside (4), and isoverbascoside (5). Their structures were elucidated by spectral data. Compound 1 showed weak enhancement of nerve growth factor (NGF)-mediated neurite outgrowth from PC12D cells.     

Iridoids and sesquiterpenoids with NGF-potentiating activity from the rhizomes and roots of Valeriana fauriei

A new iridoid glycoside, 10-isovaleryl kanokoside C (1), and a new sesquiterpene (2) together with two known compounds (3, 4) were isolated from the rhizomes and roots of Valeriana fauriei. Their structures were elucidated on the basis of spectroscopic analysis. Compounds 2 and 4 showed enhancing activity of nerve growth factor (NGF)-induced neurite outgrowth in PC 12D cells.     

New constituents from the leaves of Morinda citrifolia

A new iridoid glycoside, citrifoside (1), and a new anthraquinone, 1,5,15-trimethylmorindol (2), together with 24 known compounds, were isolated from the leaves of Morinda citrifolia. The structures of the new compounds were elucidated by spectral data. 1,5,15-Trimethylmorindol (2) did not show significant cytotoxic activity by itself but showed cytotoxicity when combined with tumor necrosis factor-related apoptosis-inducing ligand (TRAIL), while citrifoside (1) did not show any activity even with TRAIL.     

Iridoid and phenolic glycosides from the roots of Prismatomeris connata

A new phenolic glycoside, 1-O-[beta-D-glucopyranoyl-(1-->6)-beta-D-glucopyranosyl]-3,4,5-trimethoxyphenol, named prismaconnatoside (1), together with one known phenolic glycoside (2) and four aspruloside type iridoid glycosides (3-6) were isolated from the roots of Prismatomeris connata. Their structures were determined by spectroscopic and spectrometric methods. Based on the results, along with those from other studies, iridoids were suggested to be chemical markers to distinguish between P. connata and P. tetrandra, two species that are confused in traditional Chinese medicine.     

Abietane lactones and iridoids from Goldfussia yunnanensis

Two new abietane diterpene lactones (1--2), three new abietane diterpene lactone glycosides (3--5) and a new iridoid glycoside (6), together with five known compounds, were isolated from the aerial parts of Goldfussia yunnanensis. The new compounds were determined to be 18-hydroxyhelioscopinolide A (1), 18-oxohelioscopinolide A (2), 18-hydroxy-3-O-beta-D-glucopyranosylhelioscopinolide A (3), 3-O-beta-D-glucopyranosylhelioscopinolide A (4), 3-O-beta-D-galactopyranosylhelioscopinolide A (5), and 6-O-trans-cinnamoyl E-harpagoside (6) on the basis of spectral data and chemical evidence.     

Two New Megastigmane Glycosides and a New Iridoid Glycoside from Gelsemium elegans

Two new megastigmane glycosides, eleganosides A and B ( 1 and 3 , resp.), and one new iridoid glycoside, gouwenoside A ( 4 ), together with two known compounds, foliasalacioside B₁ ( 2 ) and loganin ( 5 ), were isolated from the aerial parts of Gelsemium elegans (Gardn. et Champ.) Benth. (Loganiaceae). Their structures were elucidated by spectroscopic methods including 1D‐ and 2D‐NMR techniques. The absolute configuration of 1 was determined by CD spectroscopy.     

Constituents of Cissus quadrangularis

Two new iridoids 6-O-[2,3-dimethoxy]-trans-cinnamoyl catalpol (1) and 6-O-meta-methoxy-benzoyl catalpol (2) along with a known iridoid picroside 1 (3), two stilbenes quadrangularin A (4) and pallidol (5), quercitin (6), quercitrin (7), beta-sitosterol (8) and beta-sitosterol glycoside (9) were isolated from Cissus quadrangularis Linn. The compounds 3 and 7 are first reported from this plant. The structures were elucidated by analysis of their spectroscopic data and by direct comparison with literature. This is the first reported occurrence of iridoids in C. quadrangularis.     

A new iridoid glycoside from the roots of Dipsacus asper

A new iridoid glycoside, named loganic acid ethyl ester (1), together with five known compounds: chlorogenic acid (2), caffeic acid (3), loganin (4), cantleyoside (5) and syringaresinol-4',4'-O-bis-β-D-glucoside (6) were isolated from the roots of Dipsacus asper. The structure of compound 1 was elucidated on the basis of detailed spectroscopic analyses. Lignan is isolated from Dipsacaceae species for the first time. Compounds 1, 4 and 5 had moderate neuroprotective effects against the Aβ????? induced cell death in PC12 cells.     

New Glycosidic Constituents of Abutilon pakistanicum

Pakisides A and B ( 1 and 2 , resp.), new catalpol‐type iridoid glycosides, and a new glycoside, 3 , of scutellarein have been isolated from the AcOEt‐soluble fraction of the whole plant of Abutilon pakistanicum, along with buddlejoside and lapachol. The structures of new compounds were elucidated by spectroscopic techniques including ¹H‐and ¹³C‐NMR (DEPT), and 2D‐NMR experiments.     

A new iridoid glycoside from Gardenia jasminoides

A new iridoid glycoside,6′-O-sinapoylgeniposide,was isolated from Gardenia jasminoides Ellis and its structure was elucidated on the basis of 1D and 2D NMR,HR-ESI-MS techniques.     

Iridoid,phenylethanoid and flavonoid glycosides from Forsythia suspensa

Abstract

As part of our continuing efforts to explore bioactive compounds from natural resources, a new iridoid glycoside, adoxosidic acid-6′-oleuroperic ester (1), together with one known phenylethanoid glycoside (2) and two known flavonoid glycosides (3–4) were isolated from the fruit of Forsythia suspensa. The structure of the new compound (1) was elucidated through 1D and 2D NMR spectroscopic data and HR-ESIMS. Interestingly, compound 1 was a monoterpene ester of one iridoid glycoside. Compounds 2–4 were identified as calceolarioside A (2), kaempferol-3-O-rutinoside (3), kampferol-3-O-robinobioside (4) on the basis of NMR spectroscopic data analyses and comparison with the data reported in the literature. The antiviral activity aganisist influenza A (H5N1) virus of compound 1 was studied as well.