Antitubercular triterpenes and phytosterols from Pandanus tectorius Soland. var. laevis.

Bioassay-guided chromatographic purification of the antitubercular chloroform extract of Pandanus tectorius Soland. var. laevis leaves afforded a new tirucallane-type triterpene, 24,24-dimethyl-5 beta-tirucall-9(11),25-dien-3-one (1), squalene and a mixture of the phytosterols stigmasterol and beta-sitosterol.

A new prenylated dihydrochalcone from the leaves of Artocarpus lowii.

A new prenylated dihydrochalcone, 2',4'-dihydroxy-4-methoxy-3'-prenyldihydrochalcone (1), along with two known compounds, 2',4',4-trihydroxy-3'-prenylchalcone (2) and 2',4-dihydroxy-3',4'-(2,2-dimethylchromene)chalcone (3) were isolated from the leaves of Artocarpus lowii. The structures of 1-3 were elucidated by spectroscopic methods and by comparison with data reported in the literature. Compounds 1-3 showed strong free radical scavenging activity towards 2,2-diphenyl-1-picrylhydrazyl (DPPH) measured by electron spin resonance (ESR) spectrometry.

Prenylated flavonoids and related compounds of the Indonesian Artocarpus (Moraceae).

Several species of the genus Artocarpus (Moraceae) have been investigated in our laboratories during the last decade. Over 60 phenolic constituents have been discovered and characterized, including 27 new compounds from 13 Indonesian taxa of Artocarpus, namely A. champeden, A.

Isolation of gelsedine-type indole alkaloids from Gelsemium elegans and evaluation of the cytotoxic activity of gelsemium alkaloids for A431 epidermoid carcinoma cells.

Four new gelsedine-type indole alkaloids (1-4) were isolated from the leaves of Gelsemium elegans, together with 11 known alkaloids. The structures were determined as 14-acetoxygelsenicine (1), 14-acetoxy-15-hydroxygelsenicine (2), 14-hydroxy-19-oxogelsenicine (3), and 14-acetoxygelselegine (4), respectively, by spectroscopic analysis. The cytotoxic effects of 14 Gelsemium alkaloids including two new compounds (1, 2) were evaluated using the A431 human epidermoid carcinoma cell line.

Partial agonistic effect of 9-hydroxycorynantheidine on mu-opioid receptor in the guinea-pig ileum.

Mitragynine is an indole alkaloid isolated from the Thai medicinal plant Mitragyna speciosa that is reported to have opioid agonistic properties. The 9-demethyl analogue of mitragynine, 9-hydroxycorynantheidine, is synthesized from mitragynine. 9-Hydroxycorynantheidine inhibited electrically stimulated guinea-pig ileum contraction, but its maximum inhibition was weaker than that of mitragynine and its effect was antagonized by naloxone, suggesting that 9-hydroxycorynantheidine possesses partial agonist properties on opioid receptors.

Camptothecins and two new monoterpene glucosides from Ophiorrhiza liukiuensis.

Two new monoterpene glucosides, demethylsecologanol and 3'''-O-glucosylsenburiside II, were isolated from Ophiorrhiza liukiuensis (Rubiaceae) together with 23 known compounds, including camptothecins and beta-carboline-type alkaloids. Their structures were determined by spectroscopic analysis.

Potentially cytotoxic triterpenoids from the root bark of Siphonodon celastrineus Griff.

A new oleanane-triterpene, 3beta-acetoxy-11alpha-benzoyloxy-13beta-hydroxyolean-12-one (1), was isolated along with a known quinone-methide triterpene, pristimerin (2), from the root bark of Siphonodon celastrineus Griff., a Thai medicinal plant of the family Celastraceae. Their structures were determined based on spectroscopic analysis.

Indole alkaloids of a Thai medicinal herb, Mitragyna speciosa, that has opioid agonistic effect in guinea-pig ileum.

Recently, we found that mitragynine, a major constituent of Mitragyna speciosa, has an opioid agonistic activity, but its weak potency could not explain the opium-like effect of this plant. In the present study, bioassay-guided fractionation of the crude extract of the leaves of M. speciosa was carried out to search for potent opioid agonists other than mitragynine.

Structure elucidation and synthesis of lycoposerramine-B, a novel oxime-containing Lycopodium alkaloid from Lycopodium serratum Thunb.

A new alkaloid, lycoposerramine-B (1), containing an oxime function, was isolated from the club moss Lycopodium serratum Thunb. The structure of 1 was elucidated by spectroscopic analysis, including J-resolved HMBC spectroscopy, and confirmed by its synthesis from the known alkaloid, serratinine (3).

Protective effect of rhynchophylline and isorhynchophylline on in vitro ischemia-induced neuronal damage in the hippocampus: putative neurotransmitter receptors involved in their action.

Rhynchophylline and isorhynchophylline are major tetracyclic oxindole alkaloid components of Uncaira species, which have been long used as medicinal plants. In this study we examined the protective effects of rhynchophylline and isorhynchophylline on in vitro ischemia-induced neuronal damage in the hippocampus and interaction of these alkaloids with neurotransmitter receptors in a receptor expression model of Xenopus oocytes. In vitro ischemia was induced by exposing the hippocampal slices to oxygen- and D-glucose-deprived medium over 8 min.

New oleanan-type triterpene and cincholic acid glycosides from Peruvian "Uña de Gato" (Uncaria tomentosa).

A new oleanan-type triterpene and three new cincholic acid glycosides were isolated from Peruvian "Una de Gato" (Cat's claw, plant of origin: Uncaria tomentosa), a traditional herbal medicine in Peru. Their structures were determined by spectroscopic analysis.

New type of trimeric and pentameric indole alkaloids from Psychotria rostrata.

Two new tryptamine-related alkaloids, psychotrimine and psychopentamine, were isolated from the leaves of Psychotria rostrata, and their novel structures were elucidated on the basis of spectroscopic analyses.

A new 9-methoxyyohimbine-type indole alkaloid from Mitragyna africanus.

A new yohimbine-type indole alkaloid (1). was isolated from the stem bark of Mitragyna africanus (WILLD.) collected in Nigeria, along with known seven Corynanthe-type oxindole alkaloids, two secoiridoids, three lignans, and a quinovic acid derivative.

Antinociceptive effect of 7-hydroxymitragynine in mice: Discovery of an orally active opioid analgesic from the Thai medicinal herb Mitragyna speciosa.

Mitragynine is an indole alkaloid isolated from the Thai medicinal plant Mitragyna speciosa. We previously reported the morphine-like action of mitragynine and its related compounds in the in vitro assays. In the present study, we investigated the opioid effects of 7-hydroxymitragynine, which is isolated as its novel constituent, on contraction of isolated ileum, binding of the specific ligands to opioid receptors and nociceptive stimuli in mice.

Mesaconitine-induced relaxation in rat aorta: role of Na+/Ca2+ exchangers in endothelial cells.

Previously, we reported that mesaconitine, an aconite alkaloid, increased intracellular Ca(2+) concentration ([Ca(2+)](i)) level in endothelium and caused relaxation in rat aorta via nitric oxide production. In the present study, we investigated the mechanisms of increase in the [Ca(2+)](i) level induced by mesaconitine in rat aorta and in human umbilical vein endothelial cells (HUVECs). Treatment with the low Na(+) buffer delayed the 30 microM mesaconitine-, but not 10 microM acetylcholine-, induced relaxation in rat aorta.

Biosynthesis of camptothecin. In silico and in vivo tracer study from [1-13C]glucose.

Camptothecin derivatives are clinically used antitumor alkaloids that belong to monoterpenoid indole alkaloids. In this study, we investigated the biosynthetic pathway of camptothecin from [1-13C]glucose (Glc) by in silico and in vivo studies. The in silico study measured the incorporation of Glc into alkaloids using the Atomic Reconstruction of Metabolism software and predicted the labeling patterns of successive metabolites from [1-13C]Glc.

New oxindole alkaloids and iridoid from Carolina jasmine (Gelsemium sempervirens Ait. f.).

Three new gelsedine-type oxindole alkaloids, GS-1, GS-2, and GS-3, and one new iridoid, GSIR-1, were isolated from the stems and leaves of cultivated Carolina jasmine (Gelsemium sempervirens AIT. f.) and their structures were determined by spectroscopic analysis.

Ten new Lycopodium alkaloids having the lycopodane skeleton isolated from Lycopodium serratum Thunb.

Ten new alkaloids, lycoposerramines-F (1), -G (2), -H (3), -I (4), -J (5), -K (6), -L (7), -M (8), -N (9), and -O (10), having lycopodine-related structures, were isolated from the club moss Lycopodium serratum THUNB. and their structures were elucidated on the basis of spectroscopic analysis and/or chemical transformation.

Pharmacological evidence for antidementia effect of Choto-san (Gouteng-san), a traditional Kampo medicine.

To clarify the clinical efficacy of one of the traditional medicines in the treatment of patients with vascular dementia, we investigated the pharmacological activities of Choto-san in animal models. Pretreatment with Choto-san (0.75-6.

Two oligostilbenes, cis- and trans-diptoindonesin B, from Dryobalanops oblongifolia.

Two oligostilbenes, cis- and trans-diptoindonesin B, have been isolated from the tree bark of Dryobalanops oblongifolia (Dipterocarpaceae). The structures and relative configurations of both compounds were determined on the basis of spectroscopic evidence, including 2D-NMR spectroscopic analysis.

First asymmetric total synthesis of Us-7 and -8, novel D-seco Corynanthe-type oxindole alkaloids from Uncaria attenuata: structure revision of Us-7 and determination of absolute stereochemistry.

[reaction: see text] Starting from (S)-glycidol, the asymmetric total synthesis of novel D-seco Corynanthe-type oxindoles Us-7 and Us-8 was accomplished. The structure of Us-7 was revised from the reported structure 1 with the (3R,7S) form to structure 22 with (3S,7R), and the absolute stereochemistry at C15 of both alkaloids was established.

Structure reinvestigation of gelsemoxonine, a constituent of Gelsemium elegans, reveals a novel, azetidine-containing indole alkaloid.

[structure: see text] The structure of gelsemoxonine, isolated from Gelsemium elegans Benth., was revised to be a novel oxindole alkaloid having an azetidine unit. A new alkaloid, 14,15-dihydroxygelsenicine, which was presumed to be a biosynthetic precursor of gelsemoxonine, was also isolated.

Camptothecin biosynthetic genes in hairy roots of Ophiorrhiza pumila: cloning, characterization and differential expression in tissues and by stress compounds.

Camptothecin derivatives are clinically used anti-tumor compounds that biogenetically belong to a group of monoterpenoid indole alkaloids (TIA). We have already established a hairy root culture of Ophiorrhiza pumila (Rubiaceae) that produces camptothecin. The present study describes the cloning and characterization of cDNAs encoding strictosidine synthase (OpSTR; EC 4.

Metabolite profiling of alkaloids and strictosidine synthase activity in camptothecin producing plants.

Camptothecin derivatives are clinically used anti-neoplastic alkaloids that biogenetically belong to monoterpenoid indole alkaloids. Camptothecin-related alkaloids from the methanol extracts of Ophiorrhiza pumila, Camptotheca acuminata and Nothapodytes foetida plants were profiled and identified using a reverse-phase high performance liquid chromatography coupled with on-line photodiode array detection and electrospray-ionization ion-trap mass spectrometry. A natural 10-glycosyloxy camptothecin, chaboside, was accumulated in tissues of O.