Synthesis and characterization of a new organic-inorganic hybrid ferroelectric: (C4H10N)6[InBr6][InBr4]3·H2O.

Organic-inorganic hybrid ferroelectric materials have attracted attention from researchers as promising candidates for functional materials, because they combine high performance and low cost. Herein, a new organic-inorganic hybrid ferroelectric material (C4H10N)6[InBr6][InBr4]3·H2O (1) was synthesized and characterized. The compound undergoes a paraelectric-ferroelectric phase transition at TC = 232 K, which is investigated by differential scanning calorimetry (DSC), dielectric measurements and variable-temperature structural analyses. Crystal structure analyses indicated that the disorder-order transition of Br atoms in [InBr4]- anions depending on temperature was the main factor driving the phase transition from Pbcn to Pna21. This finding will open up a new direction to probe the organic-inorganic hybrid molecular ferroelectric phase transition materials.

Prenylated phloroglucinol derivatives from Hypericum sampsonii.

Six new acylphloroglucinol derivatives, sampsonols A-F (1-6), were isolated from the petroleum ether extract of the aerial parts of Hypericum sampsonii. The structures and relative configurations of sampsonols A-F were elucidated by extensive spectroscopic analyses. All these compounds were tested for their in vitro cytotoxic and anti-inflammatory activities. Sampsonols A and B (1 and 2) showed significant cytotoxicity against four human tumor cell lines with IC(50) values in the range of 13-28µM, whereas sampsonols C and F (3 and 6) showed potent inhibitory activities against LPS-induced NO production in RAW 264.7 macrophages with IC(50) values of 27.3 and 29.3µM, respectively.

Triterpenoid saponins from the seeds of Caragana microphylla.

Two new triterpenoid saponins, namely caraganoside C (1) and caraganoside D (2), were isolated from the seeds of Caragana microphylla. Their structures were elucidated on the basis of spectroscopic analyses, including homo- and hetero-nuclear correlation NMR experiments (COSY, HSQC and HMBC). Both 1 and 2 exhibited moderate inhibitory activity against NO production in LPS-stimulated RAW264.7 cells with IC(50) values of 26.4 µM and 32.2 µM, respectively. In addition, 1 showed weak cytotoxicity against MCF-7, HL-60, HCT116, and A549 cell lines.

Two new xanthones from Hypericum sampsonii and biological activity of the isolated compounds.

Phytochemical investigation of the CH(2) Cl(2) extract of the aerial part of Hypericum sampsonii yielded two new prenylated xanthones, hypericumxanthone A and B, together with three known xanthones. Their structures were elucidated by analysis of physical and spectral (UV, IR, mass and NMR) data and comparison of spectroscopic data with those reported previously. All these compounds were evaluated for in vitro antibacterial activity against methicillin-resistant Staphylococcus aureus (MRSA). Two new compounds were also tested for their cytotoxicity against human breast (MCF-7), hepatoma (HepG2), colon (HT-29) and lung (A549) tumour cell lines. Two new compounds showed moderate antibacterial activities at minimum inhibitory concentrations (MIC) of 16 and 32 µg/mL, respectively, whereas the positive standard antibacterial drug, vancomycin, showed an MIC of 8 µg/mL. The other compounds were inactive against MRSA. In addition, hypericumxanthone B showed weak inhibitory activities against four human tumour cell lines.

[Studies on alkalodial constituents in leaves of Uncaria hirsuta].

OBJECTIVE: To study the alkaloidial constituents of the leaves of uncaria hirsuta. METHOD: Some chromatographic methods were applied to isolate pure compounds and their structures were elucidated by spectroscopic methods. RESULT: Eleven compounds were isolated and identified as 19-epi-3-iso-ajmalicine (1), 3-isoajmalicine (2), harman (3), mitraphylline (4), isomitraphylline (5), isorhynchophylline (6), corynoxine (7), rhynchophylline (8), isomitraphyllic acid (9), uncarine A (10) and uncarine B (11). CONCLUSION: Compounds 1-9 were firstly isolated from this plant.