Isolation and X-ray crystal structure of a new isoquinoline-N-oxide alkaloid from Calycotome villosa subsp. intermedia

A new isoquinoline-N-oxide alkaloid was extracted from the alkaloid fraction of a methanol extract of the seeds of Calycotome villosa subsp. intermedia. Its structure was established as 1-hydroxymethyl-6,7-dimethoxyisoquinoline-N-oxide (1) by spectroscopic techniques and X-ray diffraction analysis.     

Morphinandienone alkaloids from Dehaasia longipedicellata

Five morphinoid alkaloids have been isolated from Dehaasia longipedicellata, namely (-) pallidine, a new alkaloid (+) pallidinine (1), (+)-milonine, (-) 8,14-dehydrosalutaridine and (-) sinoacutine.     

8-demethoxyrunanine from Sinomenium acutum

A new hasubanane-type alkaloid, named 8-demethoxyrunanine, was isolated from the rhizome of Sinomenium acutum. Its structure was determined by spectroscopic methods and X-ray diffraction analysis.     

A new benzophenanthridine alkaloid from Zanthoxylum buesgenii

A new benzophenanthridine alkaloid, 6-[2'-ethoxy-2'-(2',4',5'-trimethoxyphenyl)] ethyl-7,8-dimethoxy-5-methyl-2,3-methylenedioxy-5,6-dihydrobenzo[c]phenanthridine named buesgeniine (1), as well as the known decarine, were isolated from the extract of the stem bark of Zanthoxylum buesgenii. In addition, three known lignans, sesamine, matairesinol dimethylether, and methylpluviatilol, were also identified. The structure of 1 was elucidated using spectroscopic methods.     

A novel aporphine alkaloid from Magnolia officinalis

A novel aporphine alkaloid, magnofficine (1), has been isolated from the root barks of the Chinese medicinal plant Magnolia officinalis, along with seven known compounds. Elucidations of their structures were achieved by spectroscopic methods. Magnofficine is the first example of an adduct of aporphine alkaloid and 4-hydroxyphenethylamino bridged by a methylene.     

A new oxoaporphine alkaloid from Sinofranchetia chinensis

A new oxoaporphine alkaloid, sinofranine, was isolated from the stem of Sinofranchetia chinensis. The structure of the new alkaloid was elucidated by a combination of spectral methods (IR, MS, 1H and 13C-NMR, NOED and COSY).     

Alkaloids from Sarcomelicope megistophylla

Two new alkaloids were isolated from the bark of Sarcomelicope megistophylla. Cyclomegistine B (1), a new quinolone alkaloid, that possesses a rare cyclobuta[b]quinoline ring system and sarcomejine B (2) which is a quinolone alkaloid with an unusual side chain. The structure of both compounds was elucidated on the basis of MS data and extensive NMR studies.     

Millaurine A, a new guanidine alkaloid from seeds of Millettia laurentii

A new guanidine alkaloid, millaurine A (1), was isolated from the methanol extract of the seeds of Millettia laurentii. The structure of the new compound was elucidated on the basis of spectral analysis.     

Bisindole alkaloids and secoiridoids from Alstonia macrophylla Wall. ex G. Don

The ethanolic extract from stems of a Thai medicinal plant, Alstonia macrophylla Wall. ex G. Don (Apocynaceae) showed a significant inhibitory effect on acetylcholinesterase (AChE) determined by using Ellman assay. Four compounds i.e., a bisindole alkaloid, macralstonine (1), a new bisindole alkaloid, thungfaine (2), a secoiridoid glycoside, sweroside (3) and a new secoiridoid glycoside, naresuanoside (4) were isolated. Compound 4 showed moderate AChE and butyrylcholinesterase (BChE) inhibitory effects. Interestingly, compound 4 inhibited cell growth on human androgen-sensitive prostate cancer cell line (LNCaP) but no effect on viability of human foreskin fibroblast cells (HF).     

Five new alkaloids from Coptidis Rhizoma–Euodiae Fructus couple and their cytotoxic activities against gastrointestinal cancer cells

A new indoloquinazoline alkaloid, 10-methoxywuchuyuamide I (1), three new benzylisoquinoline alkaloids, named as coptichic aldehyde (2), coptichine (3) and 13-carboxaldehyde-8-oxocoptisine (4), and a new isoindoline alkaloid, named as coptichinamide (5), together with two known alkaloids, wuchuyuamide I (6) and 8-oxocoptisine (7) were isolated from the Coptidis Rhizoma–Euodiae Fructus couple. Their chemical structures were determined by extensive spectroscopic analyses, including IR, UV, EI–MS, HRESI–MS, 1D and 2D NMR data (¹H NMR, ¹³C NMR, ¹H–¹H COSY, HSQC and HMBC). Cytotoxicities of the isolated alkaloids against NCI-N87 and Caco-2 cell lines were evaluated. Four benzylisoquinoline alkaloids 2–4 and 7 showed inhibitory activities against NCI-N87 cell with IC₅₀ values range from 8.92 to 35.98 μM. The alkaloid 3 was a new antiproliferation compound against NCI-N87 cells. The results provided valuable information for further investigation of alkaloid 3 as a chemopreventive agent.     

Cassine, an antimicrobial alkaloid from Senna racemosa

The leaves of Senna racemosa yielded the piperidine alkaloid cassine and an inositol methyl ether. Antimicrobial screening of the compounds revealed antibacterial activity of cassine with minimum inhibitory concentrations of 2.5 mg/ml for Staphylococcus aureus and Bacillus subtilis and 5.0 mg/ml for Candida albicans.     

Distribution of anticancer drug camptothecin in Nothapodytes foetida

The topoisomerase I-DNA inhibitor alkaloid camptothecin has been evaluated from the various parts of Nothapodytes foetida. The bark contained 0.27% dry wt of camptothecin and 0.11% dry wt 9-methoxycamptothecin followed by the root, stem, and leaves. Immature seeds contained higher concentrations of camptothecin (0.32% dry wt) and 9-methoxycamptothecin (0.16% dry wt) compared to mature seeds. Various parts of mature and immature seeds were analysed to determine the content of the major alkaloids. Zygotic embryos of immature seeds contained 0.11% dry wt of camptothecin and 0.04% dry wt of 9-methoxycamptothecin. The highest concentration of camptothecin (0.42% dry wt) and 9-methoxycamptothecin (0.18% dry wt) were accumulated in the cotyledons of immature seeds.     

New bisbenzylisoquinoline alkaloid from Laureliopsis philippiana

Phytochemical investigation of Laureliopsis philippiana resulted in isolation of a new bisbenzylisoquinoline alkaloid (1) named laureliopsine A. The structure was established by spectroscopic methods, including 2D homo- and heteronuclear NMR experiments. This finding of a bisbenzylisoquinoline alkaloid in Laureliopsis supports its close relationship to Atherosperma and its taxonomic segregation from Laurelia.     

A new quinazolinedione alkaloid from the fruits of Evodia officinalis

A new quinazolinedione alkaloid, wuchuyuamide IV (1) was isolated from the fruits of Evodia officinalis.1 showed moderate cytotoxicity against Hela and HT1080 cell lines.     

A new steroidal alkaloid from the seeds of Holarrhena antidysenterica

A new steroidal alkaloid, named antidysentericine, has been isolated from the seeds of Holarrhena antidysenterica and characterized as 3 beta-dimethylaminocon-5-enin-18-one (1).     

CNS activity of Alstonia macrophylla leaf extracts: an ethnomedicine of Onge of Bay Islands

Methanol extract at 100-200 mg/kg p.o. and major nonpolar fraction B at 50 mg/kg of Alstonia macrophylla leaves caused a significant reduction in spontaneous activity, remarkable decrease in exploratory behavioural pattern, a reduction in muscle relaxant activity and also significantly potentiated phenobarbitone sodium-induced sleeping time. The phytochemical study of crude leaf extract revealed the presence of tannin, triterpenoid, flavonoid, sterol, alkaloid and reducing sugars. Further fractionation and purification of the n-butanol part of methanol extract yielded fraction A, fraction B and fraction C along with some minor fatty acids as the major compounds.     

Cyclopeptide alkaloids from Zizyphus jujuba.

A new cyclopeptide alkaloid, jubanine-C (1), together with known alkaloids scutianine-C (4) and zizyphine-A (5), have been isolated from the stem bark of Zizyphus jujuba and identified by spectral analysis.     

Alkaloids from Sophora flavescens Aition

Although the quinolizidine alkaloids and flavonoids, the main active components of the traditional Chinese medicine Sophora flavescens, have been largely investigated, a new matrine alkaloid derivative 9α-hydroxy-7,11-dehydromatrine (1) and a rare 1,4-diazaindan-type alkaloid flavascensine (17), together with 15 known alkaloids, were isolated from S. flavescens. The structures were established on the basis of spectroscopic techniques.     

A new phenanthridine alkaloid from Hymenocallis x festalis

Investigation of the alkaloid fraction of the bulbs of Hymenocallis x festalis yielded a new natural product, 3-methoxy-8,9-methylenedioxy-3,4-dihydrophenanthridine (1). The structure was elucidated on the basis of spectroscopic data.     

Two 22S-solanidine-type steroidal alkaloids from Fritillaria anhuiensis

Phytochemical investigation of the fresh bulbs of Fritillaria anhuiensis S. C. Chen et S. E. Yin, resulted in the isolation of a known steroidal alkaloid solanidine of (22S,25S)-solanid-5-en-3β-ol (1), which has never yet been found as a natural substance, and of a new steroidal alkaloid (22S,25S)-solanid-5,20(21)-dien-3β-ol. Compounds 1 and 2 were the first solanidine-type alkaloids with 22-S configuration discovered from nature. Their structures were elucidated based on spectroscopic analysis, including 1D and 2D NMR experiments.