Iridoid glucosides from Melampyrum

Melampyrum arvense and M. cristatum contain, besides aucubin, 8-epiloganin and melampyroside, a new natural iridoid glucoside: gardoside methyl ester. In addition, M. arvense contains mussaenoside and M. cristatum mussaenosidic acid, another novel iridoid glucoside.     

Iridoid glucosides from Pedicularis

Pedicularis palustris contains the iridoid glucosides aucubin and gardoside methyl ester, and five hydroxy derivatives of 8-epi-deoxyloganin, together with boschnaloside and three hydroxy derivatives of boschnaloside. From P. silvatica, plantarenaloside, 8-epiloganin and euphroside have been isolated. Euphroside is also present in P. lapponica, in addition to aucubin and mussaenoside. Chemical evidence for the structure of euphroside is presented. Pedicularioside is shown to be identical with penstemoside, and the former name is thus redundant.     

Iridoid glucosides of Odontites verna

Five iridoids have been identified in the whole plant of Odontites verna.     

Iridoid glucosides from Parentucellia Viscosa

From Parentucellia viscosa a new glucosidic iridoid, gardoside methyl ester, was isolated along with bartioside, aucubin, melampyroside, shanzhiside methyl ester and 8-epiloganin. The structure of the new glucoside was confirmed by its chemical conversion into 8-epiloganin.     

A chemosystematic study of Veronica: Iridoid glucosides

Caffeoyl-catalpol, isoferuloyl-catalpol, protocatechuoyl-catalpol, benzoyl-catalpol, p-hydroxybenzoyl catalpol (catalposide), vanilloyl-catalpol and cinnamoyl-aucubin have been isolated from several Veronica species (Scrophulariaceae) in a more or less pure state. The first four compounds have never been recorded in plants before. A PC survey of forty-three species of the genus sensu lato has shown a general presence of aucubin and catalpol. They are accompanied in many of the species by a complex mixture of esters, especially esters of catalpol with aromatic acids. In only one species have aucubin esters been found. Loganin has been identified in five species, this being the first time that this compound has been found in the Scrophulariaceae. Loganin is accompanied by unidentified loganin esters in the same five species. From the systematic point of view the complex mixtures of esters of catalpol in Veronica seem to be noteworthy. Species of Globularia, Erinus, Scrophularia Verbascum, Wulfenia, Catalpa and Plantago investigated either totally lacked ester glucosides in leaves or contained mainly different types of esters. The possible systematic meaning of these results is briefly discussed.     

Iridoid glucosides from Campsis chinensis

Two new iridoid glucosides, 5-hydroxycampenoside and cachineside I, were isolated together with tecomoside from leaves of Campsis chinensis and their structures were elucidated. The absolute stereochemistry of 5-hydroxycampenoside has been established by X-ray analysis, and the structural correlation between 5-hydroxy-campenoside and tecomoside has been determined by spectral and chemical experiments.     

Iridoid glucosides in fouquieriaceae

From three Fouquieria sp. 12 iridoid glucosides were isolated and identified. Eight of these were structurally related to galioside (monotropein methylester), while four were hydroxy substitution products of deoxyloganin. In three cases the glucoside occurred together with the corresponding 10-O-acetate.     

Iridoid glucosides in Avicennia marina

2′-Cinnamoyl-mussaenoside, 10-O-(5-phenyl-2,4-pentadienoyl)-geniposide, 7-O-(5-phenyl-2,4-pentadienoyl)-8-epiloganin, and the known iridoids geniposide and mussaenoside have been isolated from a methylated extract of the leaves of Avicennia marina. Evidence is presented that the iridoids occur as the free acids in the plant. The taxonomic significance of these findings is discussed.     

Iridoid glucosides from Phlomis rotata

Two new iridoid glucosides, dehydropentstemoside and 7-epiphlomiol have been isolated from the aerial parts of Phlomis rotata and their structures elucidated by means of chemical and spectral methods. Shanzhiside methyl ester and barlerin have also been isolated and identified     

Iridoid glucosides in Griselinia, Aralidium and Toricellia

From three of five investigated species of Griselinia a new iridoid glucoside, griselinoside, was isolated. It was found to be present also in foliage of Aralidium pinnatifidum and Toricellia angulata, accompanied in the former by aralidioside another novel iridoid glucoside. The structures and absolute configurations of the two iridoids were elucidated by NMR spectroscopy and chemical conversions. From G. littoralis and T. angulata the glucosides magnolioside and syringoside respectively were isolated. ¹³C NMR spectra are given for thirteen iridoid derivatives.     

Iridoid glucosides from Satureja Vulgaris

Satureja vulgaris was shown to contain two new iridoid glucosides, 5-deoxylamiol and 4-methylantirrhinoside, as well as the known iridoid glucosides lamiol and 5-deoxylamioside. The structures of the new glucosides were established by spectroscopic studies and chemical evidence.     

Two new iridoid glucosides from Osmanthus fragrans

Two new iridoid glucosides, 10-acetoxyligustroside and 10-acetoxyoleuropein, along, with two known glucosides, acteoside and phillyrin, have been isolated from the leaves of Osmanthus fragrans Lour and their structures have been determined.     

Iridoid glucosides from Randia spinosa (Rubiaceae)

An iridoid glucoside: randinoside, along with five known iridoids: galioside, deacetylasperulosidic acid methyl ester, scandoside methyl ester, geniposide and gardenoside, were isolated from the stems of Randia spinosa. The structures were determined by spectroscopic analysis, including 2D NMR techniques.     

Two new iridoid glucosides from Gardenia jasminoides fruits

From the fruits of Gardenia jasminoides which have been employed as Chinese crude drug “Shan-zhii”, two further new iridoid glucosides, gardoside (8,10-dehydrologanic acid) and scandoside methyl ester have been isolated and their structures have been established.     

Iridoid glycosides from Galium verum

From the aerial parts of Galium verum in flower, asperuloside and V₁ iridoid were isolated. From the mother liquor obtained on recrystallizatio     

Iridoid aglycones from Deutzia scabra

Scabrogenin and deutziogenin, the stable aglycones of known iridoid glucosides scabroside and deutzioside, have been isolated from Deutzia scabra. Their structures and mutarotational equilibria were investigated by detailed analysis of ¹H NMR and ¹³C NMR data.     

Structure and configuration of unedide,an iridoid glucoside from Arbutus unedo

Unedide, a novel iridoid glucoside isolated from Arbutus unedo (Ericaceae), has been established to be 6,7-dihydro-6β-hydroxymonotropein by detailed analysis of ¹H and ¹³ C NMR spectral data.     

Two new iridoid glucosides from Mussaenda parviflora and Mussaenda shikokiana

From the leaves of Mussaenda parviflora, two new iridoid glucosides, mussaenoside and shanzhiside methyl ester were isolated and their structures e     

Iridoid glucosides from roots of Vietnamese Paederia scandens

Four iridoid glucosides, three of which are dimeric were isolated from the methanol extract of roots of Vietnamese Paederia scandens (Lour) Merrill together with the five known glucosides, paederoside, asperuloside, paederosidic acid, asperulosidic acid and geniposide. Seven sulfur-containing iridoid glucosides were also isolated. The structures of the iridoid glucosides were determined by a combination of high-resolution NMR, MS, IR and UV spectra, and chemical reaction such as acetylation.