BER催化还原一些含氮功能基化合物的研究

用强碱性阴离子交换树脂制备了硼氢阴离子交换树脂还原剂(BER),使其在氯化铜等金属化合物的催化下还原一些芳香硝基、氰基、氮氮双键等含氮功能基化合物.还研究了BER的制备条件:如温度、溶剂、不同金属化合物对还原反应的影响,并初步探讨其反应机理.     

新的聚合物支载硼氢负离子还原剂系统研究 3: 聚合物支载还原剂III

硼氢化钠的低分子还原系统研究很多,但其聚合物支载还原剂相对来说就很少,而且仅以强碱型阴离子交换树脂来制备的聚合物试剂。为了寻找用途更广泛的、新的聚合物支载还原剂,我们进行了硼氢负离子的聚合物还原系统的研究;发现能用弱酸型阳离子交换树脂制备出新的聚合物支载还原剂。前文报道了用NaBH_4的水溶液和阴离子交换树脂     

Anticancer Effects of Ursi Fel Extract and Its Active Compound,Ursodeoxycholic Acid,in FRO Anaplastic Thyroid Cancer Cells

Anaplastic thyroid cancer (ATC) is one of the most fatal human malignancies. Ursi Fel (UF) is the bile of a brown bear that has been traditionally used for heat clearance and toxin relief in Korean and Chinese medicines. In this study, we determined the anticancer effects of a UF extract and its active compound, ursodeoxycholic acid (UDCA), in FRO human ATC cells. FRO cells were treated with UF extract and UDCA at different concentrations for various durations. Cell viability was measured using an MTT assay. Cell apoptosis was investigated by flow cytometric analysis following Annexin V and propidium iodide (PI) staining, and Hoechst staining was used to observe nuclear fragmentation. The expression of pro-apoptotic (Bax, caspase-3, cytochrome c, and PARP), anti-apoptotic (Bcl-2), and angiogenetic (TGF-β, VEGF, N-cadherin, and sirtuin-1) proteins and the phosphorylation of Akt and mechanistic target of rapamycin (mTOR) were determined by western blot analysis. Treatment with UF extract at 10, 25, and 50 μg/mL and UDCA at 25, 50, and 100 μM/mL significantly inhibited the growth of FRO cells in a dose-dependent manner. Flow cytometry and Hoechst staining revealed an increase in the apoptosis of FRO cells mediated by UF extract and UDCA in a dose-dependent manner. UF extract (25 and 50 μg) and UDCA (50 and 100 μM) significantly increased the expression of Bax, caspase-3, cytochrome c, and PARP and inhibited the expression of Bcl-2, TGF-β, VEGF, N-cadherin, and sirtuin-1 in FRO cells. Furthermore, UF extract and UDCA treatment stimulated Akt phosphorylation and inhibited mTOR phosphorylation in these cells. These results indicate that UF extract and UDCA exert anticancer properties in FRO cells by inducing apoptosis and inhibiting angiogenesis via regulating the Akt/mTOR signaling pathway.     

Synthesis and Biological Evaluation of S-, O- and Se-Containing Dispirooxindoles

A series of novel S-, O- and Se-containing dispirooxindole derivatives has been synthesized using 1,3-dipolar cycloaddition reaction of azomethine ylide generated from isatines and sarcosine at the double C=C bond of 5-indolidene-2-chalcogen-imidazolones (chalcogen was oxygen, sulfur or selenium). The cytotoxicity of these dispiro derivatives was evaluated in vitro using different tumor cell lines. Several molecules have demonstrated a considerable cytotoxicity against the panel and showed good selectivity towards colorectal carcinoma HCT116 p53^+/+ over HCT116 p53^−/− cells. In particular, good results have been obtained for LNCaP prostate cell line. The performed in silico study has revealed MDM2/p53 interaction as one of the possible targets for the synthesized molecules. However, in contrast to selectivity revealed during the cell-based evaluation and the results obtained in computational study, no significant p53 activation using a reporter construction in p53wt A549 cell line was observed in a relevant concentration range.     

Secondary Metabolites from Marine Sources with Potential Use as Leads for Anticancer Applications

The development of novel anticancer agents is essential to finding new ways to treat this disease, one of the deadliest diseases. Some marine organisms have proved to be important producers of chemically active compounds with valuable bioactive properties, including anticancer. Thus, the ocean has proved to be a huge source of bioactive compounds, making the discovery and study of these compounds a growing area. In the last few years, several compounds of marine origin, which include algae, corals, and sea urchins, have been isolated, studied, and demonstrated to possess anticancer properties. These compounds, mainly from securamines and sterols families, have been tested for cytotoxic/antiproliferative activity in different cell lines. Bioactive compounds isolated from marine organisms in the past 5 years that have shown anticancer activity, emphasizing the ones that showed the highest cytotoxic activity, such as securamines H and I, cholest-3β,5α,6β-triol, (E)-24-methylcholest-22-ene-3β,5α,6β-triol, 24-methylenecholesta-3β,5α,6β-triol, and 24-methylcholesta-3β,5α,6β-triol, will be discussed in this review. These studies reveal the possibility of new compounds of marine origin being used as new therapeutic agents or as a source of inspiration to develop new therapeutic agents.     

复合还原剂硼氢化钠/三氯化铁对亚砜的还原

硼氢化钠是一种温和、高选择性的亲核还原剂。一般它只能还原醛、酮和酰氯,而对其它功能团不起作用。因而其应用范围有一定的限制。据文献报道,某些金属卤化物能有效地提高硼氢化钠的还原性能^[1]。复合还原剂硼氢化钠/三氯化铁已应用于将β-二烷基氨基共轭烯酮还原为相应的饱和γ-氨基醇^[2]。本文研究了硼氢化钠/三氯化铁对亚砜的还原反应。     

Synthesis and properties of a functionalized heterobimetallic Re(I)–Gd(III) complex as a potential dual-contrast agent for molecular imaging

In the design of dual-imaging probes, the first functionalized and neutral heterobimetallic Re(I)–Gd(III) complex, highly soluble in aqueous solutions, has been prepared. This system exhibits interesting photophysical properties (λ_em = 578 nm, ? = 1.4%) for optical imaging and substantial higher relaxivity (r₁ = 6.6 mM⁻¹ s⁻¹ at 0.47 T and 37 °C) than the clinically used MRI contrast agents. Moreover, this system incorporates an aromatic ester functionality suitable for bioconjugation.     

The Psymberin Story—Biological Properties and Approaches towards Total and Analogue Syntheses

Psymberin is a marine natural product which has attracted a great deal of interest since its isolation: While the highly cytotoxic compound was detected early on as an ingredient in a marine sponge, it took over a decade and 600 additional samples for the structure to eventually be assigned. In the last eight years fascinating synthetic and biosynthetic investigations have led to a more detailed understanding as well as a new starting point for structure–activity studies towards new antitumor compounds. The Review gives an in‐depth insight into the progress in the field of the marine polyketide psymberin and demonstrates how organic synthesis is influencing neighboring scientific subjects.     

Isomerisierung bei der Komplexbildung von 3-Acetyl-tetramsäure: Struktur und magnetische Eigenschaften des CuII- und NiII-Komplexes von 2,7-Bis(1′, 5′, 5′-trimethylpyrrolidin-2′, 4′-dion-3′ -yl)-3, 6-diazaocta-2, 6-dien

Isomerization at the Complexation of 3-Acetyltetramic Acid: Structure and Magnetic Properties of the Cu^II- and Ni^II-Complex of 2,7-Bis (1′, 5′, 5′ -trimethylpyrrolidin-2′,4′ -dion-3′ -yl)-3,6-diazaocta-2,6-dien 2,7-Bis(1′, 5′, 5′ -trimethylpyrrolidin-2′, 4′ -dion-3′ -yl)-3,6-diazaoctadien formes Cu^II and Ni^II complexes with different constitutions (because of the Z/E isomerization). Results of X-ray analysis of N,N′ -ethylenbis(1′, 5′, 5′ -trimethylpyrrolidin-2′, 4′ -dion-3′ -acetiminato)nickel(II) 1 respectively -copper(II) 2 shows, that the complexing agent in 1 occurs in the E-form, whereas the ligand of the Cu^II complex forms the Z-form. Magnetic susceptibility and shift effects of the ¹³C-NMR signals point to a weak paramagnetism of the Ni^II complex. ESR-spectra are obtained from 2 only. Furthermore, the Cu^II complex reduces the relaxation times T₁ and T₂ of ¹H and ¹⁷O nuclei spins from water. From the temperature dependence of the shortening of the relaxation times an activation energy is calculated which describes the reorientation of the copper complex in the “water matrix”.     

胺型键合反相固定相的制备及评价

首次将一种新型硅烷偶联剂--β-（3，4-环氧环已基）乙基三甲氧基硅烷（β-ECTS）与辛胺反应，然后再键合到硅胶上，得到了胺型键合固定相，并用元素分析、^13C固体核磁共振、红外光谱进行了表征。以甲醇和水为二元流动相，用包括碱性、酸性和中性有机化合物在内的混合物对该固定相进行评价，并考察了该填料的适用pH范围及水解稳定性。结果表明，该固定相具有较好的色谱性能，且在pH=2-8之间稳定性能良好，可有效地用于碱性化合物的分析分离。