Modular Access to 2-(Trifluoromethyl)pyrazolo[1,5-a]pyridines and Their Benzo Analogues through a Copper(I)-Catalyzed Radical Annulation.

A mechanistically distinctive copper-catalyzed radical annulation to valuable 2-(trifluoromethyl)pyrazolo[1,5-a]pyridines and their benzo analogues has been described for the first time. Notably, the newly developed complementary process allows the synthesis of 4- or 6-substituted target molecular entities as a single product, which was previously challenging to access by existing methods. The utility of this process is further demonstrated by the facile construction of four different ring systems, a gram-scale synthesis, and the late-stage functionalization of bioactive molecules.

Oxymatrine Promotes S-Phase Arrest and Inhibits Cell Proliferation of Human Breast Cancer Cells in Vitro through Mitochondria-Mediated Apoptosis.

Breast cancer is one of the most lethal malignancies in the world. Oxymatrine is the major effective and toxic alkaloid component which is derived from the root of Sophora flavescens AIT, a traditional Chinese medicine which is widely distributed in Asia and the Pacific Islands. In the current research study, we investigated the effects and mechanisms of action of oxymatrine on breast cancer cells. We demonstrated that the viability and single cell proliferation capability of MCF-7 and MDA-MB-231, two breast cancer cell lines which are widely used in in vitro study, were significantly suppressed in a time- and concentration-dependent manner. Furthermore, the cell cycle of breast cancer cells treated with oxymatrine was arrested at the S-phase of the cell cycle. Oxymatrine also triggered apoptosis in breast cancer cells by modulating apoptosis-related proteins, such as cleaved Caspase-3, cleaved Caspase-9 and poly(ADP-ribose)polymerase (PARP). The remarkable reduction in the ratio of Bcl-2/Bax was also observed in oxymatrine treated breast cancer cells. In conclusion, our research demonstrated that oxymatrine plays a critical role in suppressing carcinogenesis of breast cancer cells through cell cycle arrest and induction of mitochondria-mediated apoptosis, which suggests a promising application of this drug in breast cancer therapy.

Selective Hydrogen Generation from Formic Acid with Well-Defined Complexes of Ruthenium and Phosphorus-Nitrogen PN(3) -Pincer Ligand.

An unsymmetrically protonated PN(3) -pincer complex in which ruthenium is coordinated by one nitrogen and two phosphorus atoms was employed for the selective generation of hydrogen from formic acid. Mechanistic studies suggest that the imine arm participates in the formic acid activation/deprotonation step. A long life time of 150 h with a turnover number over 1 million was achieved.

Baicalein inhibits progression of gallbladder cancer cells by downregulating ZFX.

Baicalein, a widely used Chinese herbal medicine, has multiple pharmacological activities. However, the precise mechanisms of the anti-proliferation and anti-metastatic effects of baicalein on gallbladder cancer (GBC) remain poorly understood. Therefore, the aim of this study was to assess the anti-proliferation and anti-metastatic effects of baicalein and the related mechanism(s) on GBC. In the present study, we found that treatment with baicalein induced a significant inhibitory effect on proliferation and promoted apoptosis in GBC-SD and SGC996 cells, two widely used gallbladder cancer cell lines. Additionally, treatment with baicalein inhibited the metastasis of GBC cells. Moreover, we demonstrated for the first time that baicalein inhibited GBC cell growth and metastasis via down-regulation of the expression level of Zinc finger protein X-linked (ZFX). In conclusion, our studies suggest that baicalein may be a potential phytochemical flavonoid for therapeutics of GBC and ZFX may serve as a molecular marker or predictive target for GBC.

Ursolic acid induces cell cycle arrest and apoptosis of gallbladder carcinoma cells.

BACKGROUND: Ursolic acid (UA), a plant extract used in traditional Chinese medicine, exhibits potential anticancer effects in various human cancer cell lines in vitro. In the present study, we evaluated the anti-tumoral properties of UA against gallbladder carcinoma and investigated the potential mechanisms responsible for its effects on proliferation, cell cycle arrest and apoptosis in vitro. METHODS: The anti-tumor activity of UA against GBC-SD and SGC-996 cells was assessed using MTT and colony formation assays. An annexin V/PI double-staining assay was used to detect cell apoptosis. Cell cycle changes were detected using flow cytometry. Rhodamine 123 staining was used to assess the mitochondrial membrane potential (ΔΨm) and validate UA's ability to induce apoptosis in both cell lines. The effectiveness of UA in gallbladder cancer was further verified in vivo by establishing a xenograft GBC model in nude mice. Finally, the expression levels of cell cycle- and apoptosis-related proteins were analyzed by western blotting. RESULTS: Our results suggest that UA can significantly inhibit the growth of gallbladder cancer cells. MTT and colony formation assays indicated dose-dependent decreases in cell proliferation. S-phase arrest was observed in both cell lines after treatment with UA. Annexin V/PI staining suggested that UA induced both early and late phases of apoptosis. UA also decreased ΔΨm and altered the expression of molecules regulating the cell cycle and apoptosis. In vivo study showed intraperitoneally injection of UA can significantly inhibited the growth of xenograft tumor in nude mice and the inhibition efficiency is dose related. Activation of caspase-3,-9 and PARP indicated that mitochondrial pathways may be involved in UA-induced apoptosis. CONCLUSIONS: Taken together, these results suggest that UA exhibits significant anti-tumor effects by suppressing cell proliferation, promoting apoptosis and inducing 7cell cycle arrest both in vitro and in vivo. It may be a potential agent for treating gallbladder cancer.