Phytochemical analysis of Viburnum davidii Franch. and cholinesterase inhibitory activity of its dihydrochalcones.

One flavonoid (quercetin, 1) and three dihydrochalcones (6''-O-p-hydroxybenzoyl-davidioside, 2, 4'-O-methyl-davidioside, 3, and davidioside, 4) were isolated from the leaves and young branches of Viburnum davidii Franch. All the structures were identified by comparison of their spectroscopic data (NMR and MS) with those present in literature. In addition, compounds 2-4 were evaluated for their cholinesterase inhibitory (ChEI) activity, for the first time. Accordingly, compounds 2 and 4 showed significant inhibition of both acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) with IC50 values equal to 36.883 and 39.274 µM, respectively for the former and 39.504 and 43.101 µM, respectively for the latter.

Harpagide: Occurrence in plants and biological activities - A review.

In this review article, the occurrence of harpagide in the plant kingdom and its associated biological activities are presented and detailed for the first time. The presence of harpagide has been reported in several botanical families within Asteridae, and harpagide has been observed to exert a wide number of biological activities such as cytotoxic, anti-inflammatory, and neuroprotective. These results show how harpagide can be recovered from several natural sources for several pharmacological purposes even if there is a lot to still be studied. Nowadays, the interest is related to its presence in phytomedicines. Threfore, these studies are useful to support and validate the large use of several plants in the folklore medicine.

Phytochemistry, Chemotaxonomy, and Biological Activities of the Araucariaceae Family-A Review.

In this review article, the phytochemistry of the species belonging to the Araucariaceae family is explored. Among these, in particular, it is given a wide overview on the phytochemical profile of Wollemia genus, for the first time. In addition to this, the ethnopharmacology and the general biological activities associated to the Araucariaceae species are singularly described. Lastly, the chemotaxonomy at the genus and family levels is described and detailed.

Nor-Lignans: Occurrence in Plants and Biological Activities-A Review.

In this review article, the occurrence of nor-lignans and their biological activities are explored and described. Nor-lignans have proven to be present in several different families also belonging to chemosystematically distant orders as well as to have many different beneficial pharmacological activities. This review article represents the first one on this argument and is thought to give a first overview on these compounds with the hope that their study may continue and increase, after this.

A new iridoid diglycoside from Sambucus ebulus L.

The phytochemical examination of the polar constituents of Sambucus ebulus L. leaves led to the identification of patrinoside (1) and of a new diglycoside iridoid, patrinoside-aglycone-11-O-[ß-D-glucopyranosyl-(1→6)-2'-deoxy-ß-D-glucopyranoside] (trivially named as sambuloside) (2). Both of these structures have been assigned by spectroscopic means (NMR and MS).

Pedicularis L. Genus: Systematics, Botany, Phytochemistry, Chemotaxonomy, Ethnopharmacology, and Other.

In this review, the relevance of the plant species belonging to the Pedicularis L. genus has been considered from different points of view. Particular emphasis was given to phytochemistry and ethnopharmacology, since several classes of natural compounds have been reported within this genus and many of its species are well known to be employed in the traditional medicines of many Asian countries. Some important conclusions on the chemotaxonomic and chemosystematic aspects of the genus have also been provided for the first time. Actually, this work represents the first total comprehensive review on this genus.

New Dihydrostilbene Derivatives from Chloraea chrysantha.

The study of the main components of the alcoholic extract obtained from Chloraea chrysantha Poepp. led to the isolation of two new dihydrostilbene derivatives together with the known gavilein (3). The new compounds have been assigned as 3-methoxy-5-{2-[3-methoxy-2-(3-methylbut-2-en-1-yl)phenyl]ethyl}phenol (1) and 1-[2-(3,5-dimethoxyphenyl)ethyl]-3-methoxy-2-(3-methylbut-2-en-1-yl)benzene (2). The presence of compounds 1-3 is perfectly in accordance with the current botanical classification of the genus.

Lignans and secoiridoid glycosides from the stem barks of Jasminum tortuosum.

This paper reports on the first phytochemical analysis ever performed on Jasminum tortuosum Willd. This analysis, mainly carried out by means of column chromatography separation, NMR spectroscopy and mass spectrometry, led to the isolation and the identification of four compounds, namely the lignans ginkgool (1) and olivil-4'-O-ß-glucopyranoside (2) and the secoiridoids oleoside dimethyl ester (3) and oleoside 11-methyl ester (4). The presence of these compounds is significant from a chemotaxonomic point of view, confirming the correct botanical classification of the species and, from a phytochemical standpoint, may suggest its possible use in the ethno-medicinal field.

A new iridoid diglucoside from Antirrhinum siculum.

A new iridoid diglucoside has been isolated from an ethanolic extract of Antirrhinum siculum, together with five-known compounds. Its structure has been assigned as 5-O-glucopyranosyl-7α-hydroxyharpagide by spectroscopic means.

A new iridoid diglucoside from Harpagophytum procumbens.

A new iridoid diglucoside has been isolated from an aqueous extract of Harpagophytum procumbens secondary roots, together with six known compounds. Its structure has been assigned as 6'-O-glucopyranosyl-8-O-trans-coumaroylharpagide by spectroscopic means.

Iridoid glycosides from Alonsoa meridionalis.

A new iridoid glucoside has been isolated from the Chilean native Alonsoa meridionalis (L.f.) Kuntze. Its structure has been assigned as 6'-O-ß-d-glucopyranosyl-8-O-acetylharpagide (1) by using spectroscopic methods. Harpagoside (2), laterioside (3) and verbascoside (4) were also identified.

Two new non-glycosidic iridoids from Sambucus ebulus.

Two new 'Valeriana-type' non-glycosidic iridoids were isolated from the aerial parts (leaves and young branches) of Sambucus ebulus L., a perennial herbaceous species widespread in Europe. The structures were elucidated, by spectroscopic means, as 7-O-acetylpatrinoside aglycone (1) and 10-O-acetylpatrinoside aglycone (2).

New acylated salicin bis-glucosides from Viburnum veitchii.

The phytochemical study of aerial parts of Viburnum veitchii C.H. Wright, a deciduous species originary of Central China, led to the isolation of three salicin derivative bis-glucosides, i.e. henryoside (1), and the new structures 2'b-acetyl-3'b-(3-methylbutyryl)-henryoside (2) and 2'b,6'b-diacetyl-3'b-(3-methylbutyryl)-henryoside (3). In addition, luteolin, lonicerin, robustaflavone and eugenyl-ß-D-glucopyranoside were also isolated.

Iridoid glucosides from Viburnum chinshanense.

The phytochemical study of the aerial parts of Viburnum chinshanense Graebn., a species growing in Western and Central China, led to the isolation of six iridoid glucosides: the novel 10,2'-diacetylpatrinoside, 1, and the known 2'-acetyldihydropenstemide, 2'-trans- p-coumaroyl-dihydropenstemide, 2'-acetylpatrinoside, decapetaloside, and patrinoside. In addition, amentoflavone and rosarin were also isolated.