Direct amination of benzene to aniline with several typical vanadium complexes

The liquid-phase direct catalytic amination of benzene to aniline was performed in acetic acid water solvent using a series of vanadium(Ⅲ,Ⅳ,Ⅴ)complexes with N,O-or O,O-ligands as catalysts and hydroxylamine hydrochloride as the aminating agent. The vanadium complexes exhibited much higher selectivity towards the production of aniline than NaVO_3 or VOSO_4.Under the optimized conditions,an aniline yield of 42.5%and a TON of 48 with a high selectivity of above 99.9%was obtained using 0.2 mmol of[VO(OAc)_2]...     

The Synthesis of 7-[1-Aza-2-(dimethylamino)vinyl]-4-methylhydroquinolin-2-ones and their Isomerism in Different Solvents

Interesting biological activities have been reported recently for 4-methylhydro-2H-pyrano [6,5-h]-chromen-2-ones and 4-methylhydro-2H-pyrano[6,5-h]quinolin-2-ones, including excellent anti-HIV activity with DCK derivatives1 and significant cytotoxic activity with 4,8,8-trimethylhydro-2H-pyrano[6,5-h]quinolin-2-one2. These results prompted us to synthesize two series of corresponding diaza three-ring heterocyclic analogs, trihydro- pyridino[2,3-h]quinolin-2-ones and hydropyridino[2,3-h]quino…     

A New Organo-Directed Titanium Phosphate Phase Containing Zigzag Chains of Corner-Sharing TiO_6 Octahedra

The chemistry of titanium phosphates has attracted considerable interests because of their applications in ion exchange, redox catalysis and outstanding non-linear optical materials. However, only a few titanium compounds have been reported, and fewer reports deal with single-crystal structure determinations due to the difficulty in obtaining large single crystals of titanium phosphates. The synthesis of titanium phosphates often leads to two-dimensional layered phases1-3, and several titanium…     

Resveratrol Tetramers from the Roots of Ampelopsis sinica

Various biological activities of stilbenoids have been described, such as antifungal and antibacterial activities1, antihepatotoxic activity2-4, anti-HIV activity5. Stilbenoids mainly existed in Vitaceae, Diperocarpaceae, Gnetaceae, Cyperaceae, Leguminase1. Many oligostilbenes have been isolated from Vitaceaeous plants. But, there was no report on the stilbenoids in Ampelopsis sinica (Miq.) W. T. Wang which was traditionari- ly used to treat arthritis6. In our study on the constituen…     

A New Flavone Glycoside from Isodon enanderianus

Isodon enanderianus (Hand.-Mazz.) H. W. Li, a perennial shrub plant of Labiatae family, is widely distributed in the southern part of Yunnan province. It has long been used as folk medicine to diminish inflammation and detoxify1. The Isodon genus is known to be rich in ent-kaurane diterpenoids, a series of new ent-kaurane diterpenoids have been isolated from the dried leaves of I. enanderianus2-4. During the course on a re-investigation of the chemical constituents of I. enanderianus, four…     

Cross-linking Copolymerization of Acrylic Acid and Multi-armed Cross-linkers

Polymer gels are of considerable interests in material science1-3. Many theoretical and experimental studies have been made on the cross-linking copolymerization4-6 of these systems. Recently, in situ interferometry is applied in studying this process7-9. As shown in Figure 1, the common two-armed cross-linkers will lead to defects in the network, while multi-armed cross-linkers will enhance the integrity of the network. This paper studies the cross-linkers influence on cross-linking and t…     

Lipase-catalyzed hydrolysis of methyl-3-phenylglycidate

Large amount of facts indicated that enantiomers were different from each other in biological activity, physiological activity and toxicity in clinical applications1. It resulted in the increase of interest on preparation of chiral drugs. Optical active 3-phenylglycidic ester, especially (2R,3S)-methyl 3-phenylglycidate is an important starting material for production of many chiral drugs, such as taxol, (2R,3S)-diltiazem etc2,3.For the above purpose, a series of lipases were screened. Final…     

Spectroscopic Study of the Interaction of Bu_2SnCl_2 with EHPG

A number of Sn (Ⅳ)complexes have been synthesized since 1980 and tested its anticancer activity1. The simplest complex Bu2SnCl2 has activity to P388 tumor cells. Several metal complexes such as Ru-ind (trans-indazolium (bisindazole) tetrachloro- ruthenate (Ⅲ)) had used transferrin as a drug delivery system, the complexes still exhibit high antitumor activity and lower toxicity2. We use EHPG as a model ligand3 to study the interaction between Bu2SnCl2 and EHPG. EHPGAt first, we stud…     

A New Benzosesquiterpenoid Dimer from Polyalthia cheliensis Hu

The genus plants Polyalthia, being rich in bioactive diterpenoids and alkaloids1,2, have been attracting much attention. Polyalthia cheliensis Hu is a bush mainly distributed in Xishuangbanna, Yunnan Province of China. The previous researches1 reported the isolations of four clerodane diterpenes from the stem bark of this plants. Recent phytochemical work on its dried leaves results in the elucidations of a new benzosesquiterpenoid dimer, 3((, 3(((-bispolycerasoidol (1) and its monomer, a kn…     

NO Decomposition on Rh Supported CNTs

It is well known that NO is one of the most predominant pollutants. It is the main source of acid rain and has strong carcinogenicity. Therefore, removal of NO is one of the key environmental subjects in the world nowadays. With the discovery of carbon nanotubes and their large-scale synthesis1-2, attention is now being focused on their potential application in various fields of materials research. In the field of heterogeneous catalysis, numerous carbon materials have been used to disperse …