Antimicrobial glycoalkaloids from the tubers of Stephania succifera.

Three new glycoalkaloids, N-formyl-asimilobine-2-O-β-D-glucoside (1), (-)-1-O-β-D-glucoside-8-oxotetrahydropalmatine (2), and 1-N-monomethylcarbamate-argentinine-3-O-β-D-glucoside (3) were isolated from tubers of Stephania succifera. The structures were established based on spectroscopic analysis, and the antimicrobial activities of the three glycoalkaloids are reported.

A new 2-(2-phenylethyl)chromone derivative in Chinese agarwood 'Qi-Nan' from Aquilaria sinensis.

Phytochemical analysis of the high quality Chinese agarwood 'Qi-Nan' originating from Aquilaria sinensis (Lour.) Glig led to the isolation of a new 2-(2-phenylethyl)chromone derivative, qinanones G (1), and four known 2-(2-phenylethyl)chromones (2-5). Their structures were elucidated by spectroscopic techniques (UV, IR, 1D and 2D NMR) and MS analyses.

[Chemical constituents from stems of Aquilaria sinensis].

Objective: To study the constituents from the stems of Aquilaria sinensis.

Method: The chemical constituents were isolated by various column chromatographic methods. The structures were identified by spectral analysis including NMR and MS data.

Characterization and determination of 2-(2-phenylethyl)chromones in agarwood by GC-MS.

Agarwood is the fragrant resinous heartwood obtained from certain trees in the genus Aquilaria belonging to the family Thymelaeaceae. 2-(2-Phenylethyl)chromones and characteristic sesquiterpenes are the main classes of aromatic compounds isolated from agarwood. Although there are many sesquiterpenes, relatively few 2-(2-phenylethyl)chromones have been determined in agarwood by GC-MS.

2-(2-phenylethyl)chromone derivatives in Chinese agarwood "Qi-Nan" from Aquilaria sinensis.

Five new 2-(2-phenylethyl)chromone derivatives, qinanones A-E (1-5), together with eight known 2-(2-phenylethyl)chromone derivatives (6-13), were isolated from the Et2O extract of high-quality Chinese agarwood "Qi-Nan" originating from Aquilaria sinensis. The structures of the new 2-(2-phenylethyl)chromones were elucidated by spectroscopic techniques (UV, IR, 1D and 2D NMR) and MS analyses. In the bioassay for acetylcholinesterase inhibitors, compounds 1-6, 10, and 12 exhibited weak inhibitory activities (inhibition percentage ranged from 10 % to 24 % at the concentration of 50 µg/mL).

Two new types of bisindole alkaloid from Trigonostemon lutescens.

Six unprecedented bisindole alkaloids, trigolutesins A and B (1-2) with a unique polycyclic skeleton and trigolutes A-D (3-6) with another polycyclic skeleton, were isolated from the twigs of Trigonostemon lutescens. Their structures and relative configurations were elucidated by spectroscopic data and single-crystal X-ray diffraction crystallography. Trigolutesin A (1) showed weak AChE inhibitory activity.

A new antibacterial denitroaristolochic acid from the tubers of Stephania succifera.

A new denitroaristolochic acid, demethylaristofolin C (1), together with six known alkaloids, crebanine N-oxide (2), (-)-sukhodianine-β-N-oxide (3), palmatine (4), corydalmine (5), dehydrocorydalmine (6), and corynoxidine (7), was isolated from the tubers of Stephania succifera. The structure of demethylaristofolin C was elucidated by spectroscopic techniques (UV, IR, 1D, and 2D NMR) and HR-ESI-MS analyses. These compounds exhibited antibacterial activities against Staphylococcus aureus and methicillin-resistant S.

1H magnetic resonance spectroscopy study of thalamus in treatment resistant depressive patients.

Treatment-resistant depression (TRD) is a common clinical problem, and represents a considerable challenge to treatment, however, the pathogenesis of this disease is poorly understood. Thalamus is generally believed to have a role in the pathophysiology of depression. In this study, we adopted 1.

Neurogenesis and major depression: implications from proteomic analyses of hippocampal proteins in a rat depression model.

Major depression is one of the most disabling disorders. Yet, the pathogenesis of this mental disorder is poorly understood. Hippocampus is generally believed to be associated with pathogenesis of depression.