Search

Calycanthine, the principal alkaloid of the order Calycanthaceae, has been isolated from a species of the genus Psychotria (Rubiaceae) occurring in some Pacific islands. The drug is considered as a very powerful convulsant poison but very little is known about its mechanism of action. The symptoms observed were similar to those of some neuropoisons such as strychnine. The properties of this alkaloid have been investigated on the genesis, conduction, and transmission of the nerve impulse, using giant axons of the cockroach (Periplaneta americana). Calycanthine hydrochloride (10(-5) M), which did not alter nervous conduction in pre- and post-synaptic fibers, significantly reduced the efficacy of the synaptic transmission.

Several kinds of loline-type alkaloids, norloline, loline, N-acetylnorloline, N-acetylloline, N-formylnorloline, N-formylloline and N-methylloline were detected in the urine of race-horses. Furthermore, a new compound of the alkaloids, N-senecioylnorloline, was also found and identified. These compounds were mainly identified by means of gas chromatography-mass spectrometry (GC-MS) and gas chromatography-fourier transform-infrared spectrometry (GC-FT-IR). A certain plant of Gramineae containing four kinds of loline-type alkaloids was found in a bale of hay used for the horse forage. The taxonomic feature of the plant was different from known plants containing loline-type alkaloids. The common fragmentation of loline-type alkaloids under electron ionization was briefly discussed.

The furanoacridone alkaloid isogravacridonchlorine has been isolated from the roots of Ruta graveolens, the structure was elucidated by spectroscopic means. Its mutagenic activity and mode of action was characterized without as well as with metabolic activation using different Salmonella typhimurium strains.

Taxol content in various parts of several Taxus species have been determined. The weight percent ranged from 0.00003 to 0.069.

Two new biocidal quinolinone alkaloids, 3-methoxy-1-methyl-2-propyl-4-quinolone [1] and 2(1'-ethylpropyl)-1-methyl-4-quinolone [2], were efficiently isolated using reversed-phase recycling hplc from the leaves of Esenbeckia leiocarpa. The structures were determined through spectroscopic data and confirmed by total synthesis. These alkaloids have antifeedant activities against the pink bollworm, Pectinophora gossypiella.

The stem and stem bark of Polyalthia longifolia afforded the cytotoxic aporphine alkaloid liriodenine [1], as well as two aporphine alkaloids, noroliveroline [2] and oliveroline-beta-N-oxide [3] and three azafluorene alkaloids, darienine [4], polyfothine [6], and isooncodine [7], which are not bioactive. Polyfothine [6] and isooncodine [7] are new natural compounds.

New sources for the antitumor natural product taxol [1] are needed as demands for this promising cancer chemotherapeutic agent increase. Presently, supplies of taxol for clinical studies are obtained from the bark of Taxus brevifolia, a potentially limited source. Using analytical methods, the needles and stems of six Taxus species have been examined for taxol [1] and 10-deacetylbaccatin III [5], a related compound that can be converted to taxol through a semi-synthetic route. Amounts of taxol comparable to quantities reported from the bark of T. brevifolia were found in the needles of four of the Taxus species investigated. In addition, taxol was isolated from the needles of one Taxus species. Thus, Taxus needles may provide a renewable source of this valuable compound.

Fragmentation of protonated molecular ions produced from catharanthine, tabersonine, ajmalicine and serpentine in a high-performance liquid chromatography (HPLC) thermospray ion source was studied. Collision-induced dissociation (CID) of the compounds was achieved by merely increasing the repeller potential; i.e. no discharge current was applied and filament was not on. Proportion of fragments to the protonated molecular ions increased with the potential at the 180-350 V range studied, but overall yield of detected ions decreased at the higher voltages in all cases. Comparison of fragments produced in the thermospray CID with those derived from the protonated molecular ions by colliding with argon in a triple-stage quadrupole instrument showed that the fragmentation is very similar in both cases. An analytical application for identifying the alkaloids from plant cell culture material by HPLC/mass spectrometry using the thermospray CID is described.

A new indolizidine alkaloid has been isolated from the seeds of Castanospermum [1] australe and identified as 7-deoxy-6-epi-castanospermine by ms and 1H- and 13C-nmr spectroscopy. The alkaloid is the first trihydroxylated indolizidine to be isolated from this plant and may represent an intermediate in the biosynthetic pathway to the tetrahydroxy-indolizidines and -pyrrolizidines. It inhibits amyloglucosidase and yeast alpha-glucosidase but is significantly less active as a glycosidase inhibitor than its isomer swainsonine [2] and the tetrahydroxylated alkaloids castanospermine [3], 6-epi-castanospermine [4], and australine [5].

From cell cultures of Eschscholtzia californica and their spent medium, three new benzo[c]phenanthridine alkaloids--namely 10-hydroxysanguinarine [2a], 12-hydroxychelirubine [4a], and 10-hydroxychelerythrine [7a]--and two new dihydrobenzo[c]phenanthridine alkaloids--10-hydroxydihydrosanguinarine [2b] and 12-hydroxydihydrochelirubine [4b]--together with the known constituents sanguinarine [1a], chelirubine [3a], macarpine [5a], dihydrosanguinarine [1b], dihydrochelirubine [3b], and dihydromacarpine [5b], were isolated and characterized. Structure elucidations were done by 1H nmr, decoupling experiments, and NOESY spectra. Isolated microsomes from E. californica, the site of hydroxylation activity within the cells, contained the whole set 1b to 8b of 5,6-dihydrobenzo[c]phenanthridines. A scheme for the biosynthesis of macarpine [5a] from protopine [9] via dihydrosanguinarine [1b] is presented.

Two aristololactam analogues were isolated from the extract of Saururus cernuus. One of these was the known aristololactam BII [1] (cepharanone B) and the other new, named sauristolactam [2], was shown to be the lactam of 10-aminomethyl-3-hydroxy-4-methoxyphenanthrene-1-carboxylic acid. Here we detail the first reported occurrence of compounds of the aristolactam group in the genus Saururus.

Crude sample solution prepared from the seeds of Castanosperum australe was fractionated by preparative liquid chromatography. The fractions thus obtained were subsequently analyzed by means of thermospray liquid chromatography-mass spectrometry (tsp lc-ms). Under the conditions employed, castanospermine [1], 6-epi-castanospermine [2], australine [3], 3,8-di-epi-alexine [4], and fagomine [5] could be separated and detected. The possible structures of other castanospermine-related alkaloids found in the crude sample solution are also discussed.

Lentiginosine, a dihydroxyindolizidine alkaloid, was extracted from the leaves of Astragalus lentiginosus with hot methanol and was purified to homogeneity by ion-exchange, thin-layer, and radial chromatography. A second dihydroxyindolizidine, the 2-epimer of lentiginosine, was also purified to apparent homogeneity from these extracts. Gas chromatography of the two isomers (as the TMS derivatives) showed that they were better than 95% pure; lentiginosine eluted at 8.65 min and the 2-epimer at 9.00 min. Both compounds had a molecular ion in their mass spectra of 157, and the NMR spectra demonstrated that both were dihydroxyindolizidines differing in the configuration of the hydroxyl group at carbon 2. Lentiginosine was found to be a reasonably good inhibitor of the fungal alpha-glucosidase, amyloglucosidase (Ki = 1 x 10(-5) M), but it did not inhibit other alpha-glucosidases (i.e., sucrase, maltase, yeast alpha-glucosidase, glucosidase I) nor any other glycosidases. The 2-epimer had no activity against any of the glycosidases tested.

A novel substance, isocoryne, affecting the GABA receptor complex, was isolated from the Corydalis pseudoadunca plant. The inhibitory effect of isocoryne on GABA-activated transmembrane current of single neurons isolated from trigeminal ganglia of rats was tested using concentration-clamp, voltage-clamp and intracellular perfusion techniques. Isocoryne, like other phthalide isoquinoline alkaloids with a 1S,9R isomeric form, produced an inhibitory effect on GABA-activated currents with a Ki = 10(-6) M.

The alkaloids, orientalidine, oripavine, thebaine, narceine, narceine, codeine, papaverine, isothebaine, alpenigenine and morphine react with a solution of sulfuric acid containing molybdate to give specific colors. Using the acid solution permitted the differentiation of Papaver bracteatum latex from P. orientale latex and P. pseudo-orientale latex.

The concentrations of total alkaloids and individual major alkaloids including the teratogen anagyrine were measured in various plant parts of teratogenic lupins as the plants matured. All alkaloids including angyrine were high in concentration in above-ground parts early in growth and decreased as plants matured, except for an increase in mature, intact seeds. Seeds were highest, followed by early growth leaves and stems. Roots were lowest with mature leaves and stems only slightly higher. Pregnant cows have the greatest risk of giving birth to calves with crooked calf disease when the concentration of the teratogen anagyrine is highest and the cows are in the susceptible 40-75 day gestation period when ingesting the plant.

Glaucium oxylobum Boiss and Buhse, population Ab-Ali, was demonstrated to contain one major alkaloid, glaucine (0.7%), and two minor alkaloids, O-methylatheroline and predicentrine, in the aerial parts. The root also contains protopine. Glaucine and O-methylatheroline were detected for the first time in this species, and predicentrine was detected for the first time in the Glaucium genus.

A phytochemical investigation of an alcoholic extract of the petioles of Nelumbo lutea resulted in the identification of the alkaloids N-methylasimilobine, anonaine, and roemerine. The alkaloids nuciferine, armepavine, N-nornuciferine, and N-norarmepavine, previously previously reported in the whole plant, were also identified.

Tandem mass spectrometry, applied to simple extracts of Backebergia militaris, indicated the presence of a number of new alkaloids, including fully aromatic oxygenated isoquinolines, their di- and tetra-hydro analogs, and beta-phenethylamines. These conclusions were supported by separation using radial tlc and comparison with authentic compounds. Traces of seven alkaloids new to this cactus species were identified; four (3,4,8,11) were known previously from other cacti. Three novel cactus alkaloids were identified and confirmed by synthesis as 7,8-dimethoxy-3,4-dihydroisoquinoline (12, dehydrolemaireocereine), 6,7-dimethoxyisoquinoline (13, backebergine), and 7,8-dimethoxyisoquinoline (14, isobackebergine). The last two compounds are the first simple, fully aromatic, isoquinoline alkaloids to be reported from the Cactaceae. The sensitivity of this approach to new alkaloid discovery is emphasized; the entire project consumed only 10 g of dried plant material.

Glaucium flavum Grantz, population Isfahan, contained four major alkaloids: dicentrine (0.8%), bulbocapnine (0.42%), protopine (0.35%), and salutaridine (0.2%). G. flavum Grantz, population Kazerun, contained four major alkaloids: dicentrine (1.4%), bulbocapnine (0.5%), O-methylflavinantine (0.5%), and salutaridine (0.3%); it also contained two minor alkaloids, protopine and alpha-allocryptonine. O-Methylflavinantine was found for the first time in the Papaveraceae.

TLC and GLC of an alkaloid extract of the aboveground portions of Lupinus argenteus Pursh. var. stenophyllus (Rydb.) Davis (Leguminosae) suggested the presence of sparteine, beta-isosparteine, delta5-dehydrolupanine, alpha-isolupanine, lupanine, thermopsine, and anagyrine. GLC-mass spectrometry confirmed these preliminary findings. Preparative TLC was used to isolate sparteine, and this alkaloid was further characterized by IR spectral analysis and derivatization.

Anticancer activity of certain highly cytotoxic alkaloids present in Korean mistletoe has been demonstrated in experimental animals. Unlike European mistletoe, no cytotoxic proteins were found in the Korean mistletoe.