Regioselective Propargylation of Aldehydes with Propargyl Bromide Mediated by Sn-In in Aqueous Media under Microwave Irradiation

Tin-indium were employed in the propargylations of various aldehydes with propargyl bromide in the presence of SnCl2 and C6H5（CH3）3NBr under microwave irradiation to afford the corresponding homopropargyl alcohols exclusively in high yields. All the reactions were completed smoothly in predominantly aqueous media in 200 seconds only.     

Synthesis of Two Blue-light-emitting Complexes with Schiff Base Calixarene as the Ligand

Two new blue luminescent zinc and beryllium complexes with Schiff base calixarene derivative as the ligand were prepared.Their luminescent properties were determined,which indicated that they had strong blue fluorescent properties.They also had good solubility and film formation.These new complexes can be used as blue organic electroluminescent materials (OELMs) in organic electroluminescent devices.     

Synthetic studies of the HIV-1 protease inhibitive didemnaketals: precise and stereocontrolled synthesis of the key mother spiroketal

The precise and stereocontrolled synthesis of the C₉-C₂₃ portion, the key mother spiroketal of the HIV-1 protease inhibitive didemnaketals from the ascidian Didemnum sp., has been carried out through multisteps starting from (R)-pulegone as the chiral template. This approach involved the distereoselective construction of eight chiral centers by intramolecular chiral inducement and the coupling of two fragments by Julia reaction.     

A New Cytotoxic Compound from Penicillium auratiogdseum, Symbiotic or Epiphytic Fungus of Sponge Mycale plumose

A new compound, （S）-2, 4-dihydroxy-1-butyl （4-hydroxy） benzoate （1）, and a known compound, fructigenines A （2）, were isolated from fungus Penicillium auratiogriseum derived from sponge Mycale plumose, by bioassay-guided fractionation. Their structures were established by spectroscopic and chemical methods. Both compounds show.ed cytotoxic activity against tsFT210 cells.     

DFT Calculations Indicate that 1,4‐Dihydropyridine Is a Promising Lead Antioxidant

By density‐functional‐theory (DFT) calculations, 1,4‐dihydropyridine ( 1 ) was found to be a powerful lead antioxidant with high H‐atom‐donating ability and relatively low pro‐oxidant activity. Moreover, two ethoxycarbonyl (EtOCO) substituents at C(2) and C(6) should further enhance its H‐atom‐donating ability due to resonance effects.     

A strain-induced birefringent double-clad fiber Bragg grating

A strain-induced birefringence double-clad (DC) fiber Bragg grating (FBG) is proposed and demonstrated.The grating is fabricated in the core of rectangular inner cladding double clad fiber by using phase mask method. By applying lateral strain on the grating, the birefringence is induced. In order to detect the birefringent effect of the grating, we use it as the output mirror of a laser. When lateral strain is applied,the grating becomes birefringent. Therefore, one reflection peak of double-clad fiber Bragg grating becomes two peaks and the laser also lases in two wavelengths. The wavelength spacing of the laser can be tuned from 0 to 0.8 nm. The absolute wavelengths for the two polarizations can be tuned 1.2 and 2.0 nm,respectively.     

金属-聚哇烷-硅结构的电容-电压特性

设计了metal-polysilane-silicon(MPS)结构.首次发现MPS结构具有电容-电压(C-V)特性,许多MPS结构的C-V曲线平带电压为正,且其C-V特性与聚硅烷枝化度一致,即随着聚硅烷枝化度提高,MPS结构C-V曲线明显向电压轴正向漂移.聚硅烷MPS结构有望设计成测定聚硅烷枝化度装置.     

广义射影Riccati方程方法与(2+1)维色散长波方程新的精确行波解

助于符号计算软件Maple,通过一种构造非线性偏微分方程更一般形式行波解的直接方 法,即改进的广义射影Ricccati方程方法,求解(2 1)维色散长波方程,得到该方程的新的 更一般形式的行波解,包括扭状孤波解,钟状解,孤子解和周期解．并对部分新形式孤波解画 图示意．     

Low Temperature Preparation of Titania Coated PAN Fiber and Its Photocatalytical Property

Titania thin film was deposited successfully on polyacrylonitrile (PAN) fiber by the sol‐gel process with the assistance of tetraethyl silicate (TEOS) at low temperature. It was found that the densification and crystallization of the film was a result of the post‐treatment in boiling water because of the hydrolysis of the Si‐O‐Ti bonds and dissolution of the silica component formed in the film. XRD patterns revealed the existence of anatase phase in the continuous titania layer. The product, titania coated polyacrylonitrile fiber (TiO₂/PAN), showed a high photocatalytic property and good repetition on the photodegradation of methylene blue (MB). The proposed method is expected to be used for the preparation of novel photo‐catalysts based on thermally sensitive substrates.     

A Novel Norlignan and a Novel Phenylpropanoid from Peperomia tetraphylla

A novel cyclobutane‐type norlignan, peperotetraphin (=methyl rel‐(1R,2S,3S)‐2,3‐bis(7‐methoxy‐1,3‐benzodioxol‐5‐yl)cyclobutanecarboxylate; 1 ), and a novel phenylpropanoid, i.e., methyl (2E)‐3‐(7‐methoxy‐1,3‐benzodioxol‐5‐yl)prop‐2‐enoate ( 2 ), along with three known compounds, α‐asarone (=1,2,4‐trimethoxy‐5‐[(1E)‐prop‐1‐en‐1‐yl]benzene), vanillic acid (=4‐hydroxy‐3‐methoxybenzoic acid), and veratric acid (=3,4‐dimethoxybenzoic acid), were isolated from the EtOH extract of the whole plant of Peperomia tetraphylla. Their structures were determined by spectroscopic methods, especially 1D‐ and 2D‐NMR techniques. This is the first report of naturally occurring cyclobutane‐type norlignans.