Biosynthesis, natural sources, dietary intake, pharmacokinetic properties, and biological activities of hydroxycinnamic acids.

Hydroxycinnamic acids are the most widely distributed phenolic acids in plants. Broadly speaking, they can be defined as compounds derived from cinnamic acid. They are present at high concentrations in many food products, including fruits, vegetables, tea, cocoa, and wine.

Naturally occurring xanthones; latest investigations: isolation, structure elucidation and chemosystematic significance.

In this review, an updated literature survey covering the reports of naturally occurring xanthones in the period of 2005-2008 is presented. In some 143 studies, the isolation of 264 different xanthones from 36 plant species (representing 15 genera in 6 families of higher plants), 7 species of fungi, and 1 lichen species were reported. Of these, 122 compounds were isolated for the first time from nature.

Ecstasy analogues found in cacti.

Human interest in psychoactive phenethylamines is known from the use of mescaline-containing cacti and designer drugs such as Ecstasy. From the alkaloid composition of cacti we hypothesized that substances resembling Ecstasy might occur naturally. In this article we show that lophophine, homopiperonylamine and lobivine are new minor constituents of two cactus species, Lophophora williamsii (peyote) and Trichocereus pachanoi (San Pedro).

Phytochemical investigation and hepatoprotective activity of Cupressus sempervirens L. leaves growing in Egypt.

Three phenolic compounds cosmosiin, caffeic acid, and p-coumaric acid were isolated for the first time from the leaves of Cupressus sempervirens L., together with cupressuflavone, amentoflavone, rutin, quercitrin, quercetin, myricitrin. The isolated compounds were identified using (1)H- and (13)C-NMR spectra.

Antimicrobial arylcoumarins from Asphodelus microcarpus.

A new aryl coumarin glucoside, asphodelin A 4'-O-beta-d-glucoside (1), and its aglycon, asphodelin A (2), were isolated from Asphodelus microcarpus. The structures were determined by detailed spectroscopic analysis and chemical transformation as 3-(2'-hydroxy-p-O-beta-d-glucopyranosyloxyphenyl)-4,7-dihydroxy-2H-1-benzopyran-2-one (1) and 3-(2',4'-dihydroxyphenyl)-4,7-dihydroxy-2H-1-benzopyran-2-one (2), respectively. These compounds were isolated following bioactivity-directed fractionation, using antimicrobial activity, in which 1 and 2 exhibited moderate and potent activities, respectively.

Aryl ketones from Acronychia pedunculata with cyclooxygenase-2 inhibitory effects.

1-[2,4-Dihydroxy-6-methoxy-3,5-bis(3-methylbut-2-en-1-yl)phenyl]ethanone (1), and a new aryl ketone, named acrovestenol (2), were isolated as cyclooxygenase-2 (COX-2) inhibitory principles from a CH2Cl2 extract of the bark of Acronychia pedunculata by a bioassay-guided fractionation procedure. Compound 2 inhibited COX-2 with an IC50 value of 142.0+/-2.

A Swedish collection of medicinal plants from Cameroon.

A collection of 32 botanically identified medicinal plants from the slopes of Mt. Cameroon made by two Swedish settlers in the beginning of the last century is described and the literature is followed up. The drug names were found to be unaltered during the century passed.

Prehistoric peyote use: alkaloid analysis and radiocarbon dating of archaeological specimens of Lophophora from Texas.

Two archaeological specimens of peyote buttons, i.e. dried tops of the cactus Lophophora williamsii (Lem.

Antimicrobial triterpenes from Poulsenia armata Miq. Standl.

Crude petroleum ether extract from the bark of Poulsenia armata showed antimicrobial activity. Activity-guided fractionation led to the isolation and structure elucidation of two active new triterpene derivatives, the stearate of glut-5-en-3beta-ol (1) and 3beta,28-diacetoxyurs-12-ene (4), for the first time as naturally occurring compounds. Compound 4 has previously been synthesized.

Constituents of Hypericum laricifolium and their cyclooxygenase (COX) enzyme activities.

Investigation of the aerial parts of the medicinal plant Hypericum laricifolium led to the isolation of two new natural products, hentriacontanyl caffeate (1a), nonacosanyl caffeate (1b). In addition, stigmasterol, beta-sitosterol, 3-epi-betulinic acid (2), caffeic acid (3), ferulic acid, docosanol, p-hydroxybenzoic acid, 3,4-dimethoxy benzoic acid, quercetin (4), quercetin-3-O-galactoside (5), quercetin-3-O-rutinoside (6), quercetin-3-O-rhamnoside (7), quercetin-3-O-glucuronide (8) and shikimic acid were also isolated. The structures were determined by 1D- and 2D-NMR, mass spectrometry, and chemical transformations.

New labdene iterpenes from Eupatorium glutinosum.

The new diterpene glucoside 3,15-dihydroxy-ent-labd-7-en-17-oic acid 3-O-beta-D-glucoside (1) and its aglycone (2) have been isolated from Eupatorium glutinosum. The structures were determined by IR, one- and two-dimensional NMR, high-resolution mass spectrometry, chemical transformations, and comparison of spectroscopic data with closely related diterpenes. Crude extracts showed antimicrobial and cytotoxic activities, but compounds 1 and 2 showed only antimicrobial activity.