Steroidal Alkaloids from Veratrum maackii Regel with Genotoxicity on Brain‐Cell DNA in Mice

Two new steroidal alkaloids, 23‐methoxycyclopamine 3‐O‐β‐D ‐glucopyranoside ( 1 ) and isoecliptalbine ( 2 ), were isolated from the root and rhizoma of Veratrum maackii Regel , together with five known compounds, i.e., verussurine ( 3 ), verabenzoamine ( 4 ), verazine ( 5 ), isoverazine ( 6 ), and verazinine ( 7 ). Their structures were established by extensive analysis of spectroscopic data, as well as by comparison with literature data. Compounds 1 – 7 could cause DNA damage in the cerebellum and cerebral cortex of mice in a dose‐dependent manner by using single‐cell gel electrophoresis (comet assay).     

m‐Methoxy Substituents in a Tetraphenylethylene‐Based Hole‐Transport Material for Efficient Perovskite Solar Cells

Three tetrapheynlethylene derivatives (N,N‐di(4‐methoxyphenyl)aminophenyl‐substituted tetraphenylethylene; TPE‐4DPA) with different methoxy positions (pp‐, pm‐, and po‐) have been synthesized and characterized. The methoxy groups can control the oxidation potential of the materials, and the electronic properties of the derivatives were affected by the position of the methoxy substituents. These compounds were synthesized in a facile and cost‐effective way, and were applied as hole‐transport materials in perovskite solar cells. The corresponding cell performances were compared with respect to their structure modifications, and it was found that the derivative with m‐OMe substituents showed the highest power conversion efficiency (PCE) of 15.4 %, with a J_sc value of 20.04 mA cm^?2, a V_oc value of 1.07 V, and a fill factor (FF) value of 0.72, which is higher than the p‐OMe and o‐OMe substituents. Moreover, the PCE of pm‐TPE‐4DPA is comparable with that of the state‐of‐the‐art 2,2′,7,7′‐tetrakis(N,N′‐di‐p‐methoxyphenylamine)‐9,9′‐spirobifluorene under identical conditions.     

((吡啶-3-基)甲氧基)芳酸衍生物的合成及抗血小板聚集活性

以具有活血化瘀作用的中药有效成分阿魏酸为先导物,按生物电子等排原理,设计合成了6个((吡啶-3-基)甲氧基)芳酸衍生物,其结构经IR,1H NMR,13C NMR及MS确证.体外药效筛选结果显示,部分((吡啶-3-基)甲氧基)芳酸衍生物对二磷酸腺苷(ADP)诱导的血小板聚集具有较好的抑制活性,其中化合物1a的抑制作用明...     

One‐Pot Regioselective Synthesis of Novel Oximino Ester‐Containing 1‐Aryl‐4‐chloro‐3‐oxypyrazoles as Potential Fungicides

A novel, functional‐group‐tolerant, and highly regioselective one‐pot synthesis of six 4‐chloro‐1‐aryl‐3‐oxypyrazoles, 8a – 8f , containing an oximino ester moiety has been developed. Their structures were characterized by ¹H‐ and ¹³C‐NMR, IR, MS, and elemental analyses. The regioselectivity of the reaction was also determined by single‐crystal X‐ray diffraction analysis of product 8d . The reaction pathway, proposed with the aid of DFT calculations, likely proceeds via a DMF‐catalyzed mechanism, which involves an electrophilic attack by SOCl₂ and two nucleophilic substitutions by benzyl bromide (BnBr) and Cl^?, respectively, as the key steps. A preliminary in vitro bioassay indicated that most compounds exhibited good fungicidal activities against Sclerotinia sclerotiorum and Gibberella zeae. Especially, 8d and 8e displayed higher or similar fungicidal activities compared with pyraclostrobin at the concentration of 10 μg/ml.     

新型卤代甲氧基二苯甲酮类化合物的合成及其对H2O2致人脐静脉内皮损伤的保护研究

以甲氧基和卤素取代的苯甲酸为起始原料,经过羧酸酰基化、傅克酰基化、芳香环卤代等反应合成了12个卤代甲氧基二苯甲酮类化合物,其结构经ESI-MS、1H NMR、13C NMR进行了表征和确认。通过考察其对H2O2诱导的人脐静脉内皮细胞(HUVECs)损伤的保护活性,讨论了此类化合物的构效关系。体外活性实验表明,浓度为12.5μmol/L时,化合物7a和9a对HUVECs有一定的保护活性,保护率超过50%。     

Synthesis,Characterization, and Catalytic Behavior of Methoxy- and Dimethoxy-substituted Pyridinium-Type Ionic Liquids

Synthesis of methoxy-substituted pyridinium-type ionic liquids from a nontoxic and easy method is described. Catalytic behaviors of synthesized ionic liquids were investigated with various concentrations for the Mannich reaction. We have observed that methoxy- and dimethoxy-substituted pyridinium bromides showed better catalytic behavior than other ionic liquids.     

Conductive and optical properties of PPV modified by N+ ion implantation

In this article, a soluble poly[2‐methoxy‐5‐(3′‐methyl)butoxy]‐p‐phenylene vinylene (MMB‐PPV) was synthesized by dehydrochlorination reaction and the MMB‐PPV film was implanted by nitrogen ions (N⁺) with the ion dose and energy in the range of 3.8 × 10¹⁵ to 9.6 × 10¹⁶ ions/cm² and 15–35 keV, respectively. The surface conductivity, optical absorption, optical band gap (E_g) of modified MMB‐PPV film were studied, and the third‐order nonlinear optical susceptibility (χ⁽³⁾) as well as its environmental stability of modified MMB‐PPV film were also measured by degenerate four‐wave mixing system. The results showed that the surface conductivity of MMB‐PPV film was up to 3.2 × 10^?2 S when ion implantation was performed with the energy of 35 keV at an ion dose of 9.6 × 10¹⁶ ions/cm², which was seven order of magnitude higher than that of the pristine film. UV‐Vis absorption spectra demonstrated that the optical absorption of MMB‐PPV film was enhanced gradually in the visible region followed by a red shift of optical absorption threshold and the E_g value was reduced from 2.12 eV to 1.59 eV with the increase of ion dose and energy. The maximum χ⁽³⁾ value of 2.45 × 10^?8 esu for modified MMB‐PPV film was obtained with the ion energy of 20 keV at an ion dose of 3.8 × 10¹⁶ ions/cm², which was almost 33 times larger than that for pristine film. In comparison to the reduction of 17% in the χ⁽³⁾ value of pristine MMB‐PPV film, the maximum χ⁽³⁾ value of 2.45 × 10^?8 esu for modified MMB‐PPV film decreased by over 5.3% when they had been exposed under the same ambient conditions for 90 days. © 2010 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 48: 2072–2077, 2010     

聚(2-甲氧基-5-壬氧基)对苯乙炔的合成及其电致发光性质

以对甲氧基苯酚和溴代正壬烷为原料,通过醚化、氯甲基化和脱氯化氢反应得到可溶性的聚（２－甲氧基－５－壬氧基）对苯乙炔,以其为发光层装配了聚合物单层电致发光器件,研究了它的电致发光和光致发光性质;电致发光器件具有良好的稳定性,其起亮电压为７Ｖ。聚合物的结构由ＩＲ、＾１Ｈ－ＮＭＲ及ＵＶ／Ｖｉｓ光谱得到确认。     

Synthesis and properties of functional derivatives ofN′-phosphoryl- andN′-phosphonoyldiazeneN-oxides; molecular structure ofN-(2,2-dimethyl-5-nitro-1,3-dioxan-5-yl)-N′-[methoxy(phenyl)phosphoryl]diazeneN-oxide

Methods for the synthesis of polyfunctionalN-phosphoryl- andN-phosphonoyldiazeneN-oxides containing hydroxyl, acetoxyl, and nitrate groups, and dibromoallyl and dibromopropyl fragments have been developed. The molecular structure ofN-(2,2-dimethyl-5-nitro-1,3-dioxan-5-yl)-N-[methoxy(phenyl)phosphoryl)diazeneN-oxide was established by X-ray structural analysis.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 7, pp. 1284–1289, July, 1994.     

Expanding the Scope of the Cleavable N-(Methoxy)oxazolidine Linker for the Synthesis of Oligonucleotide Conjugates

Oligonucleotides modified by a 2′-deoxy-2′-(N-methoxyamino) ribonucleotide react readily with aldehydes in slightly acidic conditions to yield the corresponding N-(methoxy)oxazolidine-linked oligonucleotide-conjugates. The reaction is reversible and dynamic in slightly acidic conditions, while the products are virtually stable above pH 7, where the reaction is in a ‘‘switched off-state’’. Small molecular examinations have demonstrated that aldehyde constituents affect the cleavage rate of the N-(methoxy)oxazolidine-linkage. This can be utilized to adjust the stability of this pH-responsive cleavable linker for drug delivery applications. In the present study, Fmoc-β-Ala-H was immobilized to a serine-modified ChemMatrix resin and used for the automated assembly of two peptidealdehydes and one aldehyde-modified peptide nucleic acid (PNA). In addition, a triantennary N-acetyl-d-galactosamine-cluster with a β-Ala-H unit has been synthesized. These aldehydes were conjugated via N-(methoxy)oxazolidine-linkage to therapeutically relevant oligonucleotide phosphorothioates and one DNA-aptamer in 19–47% isolated yields. The cleavage rates of the conjugates were studied in slightly acidic conditions. In addition to the diverse set of conjugates synthesized, these experiments and a comparison to published data demonstrate that the simple conversion of Gly-H to β-Ala-H residue resulted in a faster cleavage of the N-(methoxy)oxazolidine-linker at pH 5, being comparable (T_0.5 ca 7 h) to hydrazone-based structures.