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Syntheses, Crystal Structures, and biological Activities of Two Enantiomeric 2-Trifluoromethylthieno[2,3-d]pyrimidin-4-amine Derivatives

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Chinese Journal of Structural Chemistry 2015年第8期34卷 1224-1230页

作者： GAO Hui FU Ju ZHAO Ming-Juan SONG Xin-Jian YANG Ping ZHENG Yin Key Laboratory of Biologic Resources Protection and Utilization of Hubei Province Hubei University for Nationalities School of Chemical and Environmental Engineering Hubei University for Nationalities

Two enantiomeric 2-trifluoromethyl-6,7-dihydro-5H-cyclopenta[4,5]thieno[2,3-d] pyrimidin-4-amine derivatives were synthesized by nucleophilic substitution of two chiral amines with 4-chloro-2-trifiuoromethyl-6,7-dihydro-5H-cyclopenta[4~5]thieno[2-3-d]pyrimidine, which started from 2-amino-5,6-dihydro-4H-cyclopenta[b]thiophene-3-carbonitrile, trifluoroacetic acid （TFA） and phosphoryl trichloride via one-pot procedure. Their structures were determined by single-crystal X-ray diffraction. Enantiomer （R）-3,（R）-N-（1-phenylethyl）-2-trifluoromethyl-6,7- dihydro-5H-cyclopenta[4,5]thieno[2,3-d]pyrimidin-4-amine crystallizes in the tetragonal system, space group P43 with a = 8.6847（6）, b = 8.6847（6）, c = 22.419（2） A, V= 1690.9（3） A3, Z = 4, Dc = 1.428 g/cm^3, p = 0.228 mm-1, F（000） = 752, the final R = 0.0463 and wR = 0.1257 for 3442 observed reflections with 1〉 20（/）. Enantiomer （S）-3,（S）-N-（1-phenylethyl）-2-trifluoromethyl-6,7-dihydro- 5H-cycloperita[4,5]thieno[2,3-d]pyrimidin-4-amine crystallizes in the tetragonal system, space group P41 with a = 8.688, b = 8.688, c = 22.421 A, V = 1692.4 A3, Z = 4, Dc = 1.426 g/cm^3, μ= 0.227 mm^-1, F（000） = 752, the final R = 0.0682 and wR = 0.1806 for 3182 observed reflections with ≥20（I）. The preliminary bioassay indicated that the R-enantiomer exhibits higher antitumor activity against MCF-7 than gefitinib.

关键词： thieno[2,3-d]pyrimidine, enantiomeric pair, trifluoromethyl, antitumor activity

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Core-shell [email protected] nanoparticles supported on sepiolite nanofibers for the catalytic reduction of nitrophenols in water: Enhanced catalytic performance and DFT study

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Applied Catalysis B: Environmental 2017年 205卷 262-270页

作者： Ying Ma Xiaoyong Wu Gaoke Zhang Hubei Provincial Collaborative Innovation Center for High Efficient Utilization of Vanadium Resources State Key Laboratory of Silicate Materials for Architectures School of Resources and Environmental Engineering Wuhan University of Technology Wuhan 430070 PR China Center for Circular Economy and Clean Production South China Institute of Environmental Sciences Ministry of Environmental Protection of the People’s Republic of China Guangzhou 510655 PR China

We reported the enhanced catalytic property of core-shell [email protected] nanoparticles supported on sepiolite nanofibers for the reduction of nitrophenols in the presence of NaBH 4 . Furthermore, we confirmed the contribution of core-shell structure to the enhanced catalytic performance of [email protected] nanoparticles by DFT calculations. The [email protected] /sepiolite catalysts were prepared using a successive reduction method, in which core-shell [email protected] nanoparticles were highly dispersed on sepiolite nanofibers. DFT calculations showed that the charge redistribution and s-d hybridization between Ag cores and Pt shells contributed to the unique electronic structure of [email protected] nanoparticles. More importantly, 2 wt.% [email protected] /sepiolite catalyst exhibited much higher catalytic activity toward nitrophenols reduction than Ag/sepiolite and Pt/sepiolite, and relatively high catalytic stability even after 5 cycles. The enhanced catalytic performance of [email protected] /sepiolite catalysts was primarily owing to the large surface area and high porosity of sepiolite nanofibers and the unique electronic structure of core-shell [email protected] nanoparticles, which resulted in the effective adsorption of nitrophenols and the electron transfer from BH 4 − to nitrophenols, respectively. This study probably provides new insights into the catalytic reduction of nitrophenols in water by forming the composite between bimetallic core-shell nanoparticles and natural low-cost supports.

关键词： [email protected] Nanoparticles Sepiolite nanofibers Core-shell structure DFT Calculations Catalytic reduction of nitrophenols

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A logistic delay single-species system with an impulsive control strategy

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ICIC Express Letters, Part B: Applications 2015年第10期6卷 2693-2699页

作者： Xiang, Changcheng Yang, Yi Key Laboratory of Biologic Resource Protection and Utilization of Hubei Province Hubei University for Nationalities No. 39 Xueyuan Road Enshi China

A periodic delay single species system subject to linear/constant impulsive control strategy is investigated. Sufficient conditions for the permanence of the system with linear and constant impulsive perturbations are derived. Our main results show that the suitable large linear impulsive stocking is favorable for the permanence whereas the size of the positive constant impulsive stocking has irrelevant influence on the permanence. ©, 2015 ICIC Express Letters *** Rights Reserved.

关键词： Delay Linear/constant impulsive harvesting Permanence Single species periodic system

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Variation of nitric oxide emission potential in plants: a possible link to leaf N content and net photosynthetic activity

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Journal of Plant Ecology 2015年第3期8卷 313-320页

作者： Juan Chen Chao Wang Fei-Hua Wu Wen-Hua Wang Ting-Wu Liu Juan Chen Qiang Xiao Bin-Yuan He Hai-Lei Zheng Key Laboratory for Subtropical Wetland Ecosystem Research of MOE College of the Environment and EcologyXiamen UniversityXiamen 361005China State Key Laboratory of Soil and Sustainable Agriculture Institute of Soil ScienceChinese Academy of SciencesNanjing 210008China Laboratory of Biological Resources Protection and Utilization of Hubei Province Hubei Institutes for NationalitiesEnshi 445000China Guangxi Academy of Oceanography Naning 530022China

Aims Ecological systems,especially soils,have been recently recognized as an important source of atmospheric nitric oxide(No).However,the study on the contribution of plants to atmospheric No budget is significantly *** specific objectives of this study are to reveal the phylogenetic variation in No emission potential existing in various plant species and find out the possible leaf traits affecting No emission *** We measured No emission potential,leaf N and C content,C:N ratio,specific leaf area,net photosynthetic rate(Pn)and estimated photosynthetic N use efficiency(PNuE)of 88 plant *** investigation of the relationships between No emission potential and leaf traits were performed by simple linear regression analysis and pair-wise correlation coefficients *** Findingsmajor results are as follows:(1)No emission from plant species exhibited large variations,ranging from 0 to 41.7 nmol m^(−2) h^(−1),and the species frequency distributions of No emission potential could be fitted to a log-normal curve.(2)among 88 species,No emission potential was the highest in Podocarpus macrophyllus,but lowest in Zanthoxylum nitidum and Vernicia montana.(3)No emission potential has strong correlation to leaf N content,Pn and *** variations in No emission potential among diverse plant species may be closely related to leaf N level and net photosynthetic ability.

关键词： leaf N content leaf trait net photosynthetic rate nitric oxide phylogenetic variation

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Theoretical Study on the Electronic Structures and Spectral Properties of 1,8-Naphthalimide Derivatives

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Chinese Journal of Structural Chemistry 2014年第6期33卷 813-820页

作者：王艳高慧杨平聂光华宋新建 Key Laboratory of Biologic Resources Protection and Utilization of Hubei Province Hubei Minzu University College of Forestry and Horticultrue Hubei Minzu University

The molecular geometries, frontier molecular orbital properties, and absorption and emission properties of three 4-phenoxy-1,8-naphthalimide derivatives, namely 4-phenoxy-N-（2-hydroxyethyl）-1,8-naphthalimide（1）,4-（2-tert-butylphenoxy）-N-（2-hydroxyethyl）-1,8-naphthalimide（2）, and 4-[2,4-di（tert-butyl）]phenoxy-N-（2-hydroxyethyl）-1,8-naphthalimide（3）, are investigated by density functional theory（DFT） and time-dependent density functional theory（TD-DFT） calculations in conjunction with polarizable continuum models（PCMs）. Four functionals and ten basis sets are employed for 1 to calculate the electron transition energies, which were compared with the experimental observations. Our results reveal that the B3LYP/6-311＋G（d,p） method is the best choice to reproduce the experimental spectra. Moreover, the effects of substituents on the molecular geometries, electronic structures, absorption and emission spectra are also studied at the B3LYP/6-311＋G（d,p） level. We find that the gap between the highest occupied molecular orbital（HOMO） and the lowest unoccupied molecular orbital（LUMO） decreases with increasing the number of tert-butyl substituents onto the phenoxy groups, suggesting red-shift of the absorption and emission bands. This is related to the increase of conjugation from 1 to 2 and 3. Our calculations are in good agreement with the experimental results.

关键词： 1 8-naphthalimide derivatives density functional theory frontier molecular orbital absorption spectrum emission spectrum

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Synthesis, Crystal Structure, and Antitumor Activity of 1-(4-Methoxybenzylidene)-2-(1-phenyl-6-trifluoromethyl-1H-pyrazolo[3,4-d]pyrimidin-4-yl)hydrazine Monohydrate

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Chinese Journal of Structural Chemistry 2014年第8期33卷 1129-1134页

作者：杨平高慧宋新建 Key Laboratory of Biologic Resources Protection and Utilization of Hubei Province Hubei Minzu University College of Forestry and Horticultrue Hubei Minzu University

The novel title compound 1-（4-methoxybenzylidene）-2-（1-phenyl-6-trifluoromethyl- 1H-pyrazolo[3,4-d]pyrimidin-4-yl）hydrazine monohydrate （C20HisF3N60-H20, Mr = 430.40） has been synthesized by a four-step procedure including the cyclization, chlorination, hydrazinolysis and condensation reaction, and its crystal structure was determined by single-crystal X-ray diffraction. The crystal belongs to orthorhombic, space groupPbca with a = 8.3779（13）, b = 17.607（3）, c = 26.774（4） A, V= 3949.2（11） A3, Z=8, Dc = 1.448 g/cm3, μ = 0.117 mm-l, F（000） = 1776, the final R = 0.0553 and wR = 0.1516 for 2354 observed reflections with 1 〉 2σ（/）. X-ray diffraction analysis reveals that the title compound is almost coplanar except for the trifluoromethyl and phenyl moieties. In the crystal packing, the molecules are linked by intermolecular O（lW）-H（1WA）-＂N（2）, O（1W）-H（1WA）.--N（4） and N（5）-H（5A）...O（lW） hydrogen bonds via water molecules and stacked through π-π stacking interactions. The preliminary bioassay suggested that the title compound exhibits relatively good antitumor activity against HepG2 and BCG-823.

关键词： pyrazolo[3,4-d]pyrimidine hydrazone trifluoromethyl antitumor activity

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Syntheses, Crystal Structures, and Antitumor Activities of Two 2-Trifluoromethyl-5,6,7,8-tetrahydrobenzo-thieno[2,3-d]pyrimidin-4-amine Derivatives

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Chinese Journal of Structural Chemistry 2014年第12期33卷 1789-1795页

作者：聂瑶黄东海王发松但悠梦赵金顺宋新建 Key Laboratory of Biologic Resources Protection and Utilization of Hubei Province Hubei University for Nationalities School of Chemical and Environmental Engineering Hubei University for Nationalities

Two novel 2-trifluoromethyl-5,6,7,8-tetrahydrobenzo[4,5]thieno[2,3-d]pyrimidin-4-amine derivatives were synthesized by nucleophilic substitution of two appropriate amines with 4-chloro-2-(trifluoromethyl)-5,6,7,8-tetrahydrobenzothieno[2,3-d]pyrimidine, which started from 2-amino-4,5,6,7-tetrahydrobenzo[b]thiophene-3-carbonitrile, trifluoroacetic acid(TFA) and phosphorous oxychloride by one-pot procedure. Their structures were determined by single-crystal X-ray diffraction. Compound 1, N-(furan-2-ylmethyl)-2-trifluoromethyl-5,6,7,8-tetrahydrobenzothieno[2,3-d]pyrimidin-4-amine, crystallizes in the monoclinic system, space group C2/c with a = 26.352(3), b = 7.5991(8), c = 17.1423(18) A, β = 114.667(2)°, V = 3119.5(6) A3 and Z = 8. Compound 2, N-(3-silatranylpropyl)-2-trifluoromethyl-5,6,7,8-tetrahydrobenzothieno[2,3-d]pyrimidin-4-amine, crystallizes in the monoclinic system, space group P21/n with a = 13.4394(13), b = 8.9446(9), c = 18.9657(18) A, β = 101.9640(10)°, V = 2230.3(4) A3 and Z = 4. The preliminary bioassay indicated that compound 2 exhibits more potent antitumor activity against BCG-823 than 5-fluorouracil(5-FU).

关键词： thieno[2,3-d]pyrimidine facile synthesis trifluoromethyl antitumor activity

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Facile synthesis and antitumor activity of novel 2-trifluoromethylthieno[2,3-d]pyrimidine derivatives

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Chinese Chemical Letters 2014年第7期25卷 1006-1010页

作者： Xin-Jian Song Ping Yang Hui Gao Yan Wang Xing-Gao Dong Xiao-Hong Tan Key Laboratory of Biologic Resources Protection and Utilization of Hubei Province Hubei Minzu University College of Forestry and Horticulture Hubei Minzu University

A series of novel 2-trifluoromethylthieno[2,3-d]pyrimidine derivatives were synthesized by a facile three-step procedure that afforded advantages of mild reaction conditions, simple protocol and good yields. The structures of the final compounds were confirmed by 1R, NMR, El-MS, elemental analysis, and X-ray diffraction. Preliminary bioassay results showed that some of the analogs exhibit excellent antitumor activity against MCF-7 and HepG2, especially compounds 3a, 3b, 3e and 3h exhibited higher activity than the positive control gefitinib.

关键词： Thieno[2,3-d]pyrimidine Gewald reaction Trifluoromethyl Facile synthesis Anritumor activity

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Synthesis and Crystal Structure of a New Complex [Cu(C_(14)H_9O_3)_2(C_5H_5N)_2(C_2H_5OH)_2]

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Chinese Journal of Structural Chemistry 2014年第5期33卷 753-756页

作者：胡卫兵宋楠楠黄猛冯驸田大听周红艳宋新建 Key Laboratory of Biological Resources Protection and Utilization of Hubei Province Hubei Institute for Nationalities

The title compound of Cu（C14H9O3）2（C5H5N）2（C2H5OH）2（1） was synthesized via the hy- drothermal reaction of CuCl2·2H2O and 9-hydroxy-fluorene-9-carboxylic acid（HHF） with pyridine, and characterized by elemental analysis and infrared spectra. The crystal belongs to triclinic, space group P1 with a = 8.8302（12）, b = 10.1625（14）, c = 12.2708（17）, α = 86.207（2）, β = 69.562（2）, γ = 64.932（2）o, V = 930.3（2） 3, Z = 1, Mr = 764.30, Dc = 1.364 g/cm3, F（000） = 399, S = 1.059 and μ（MoKα） = 0.644 mm-1. The final R = 0.0459 and wR = 0.1274 for 3414 observed reflections with I 〉 2σ（I）. The copper atom is six-coordinated by two oxygen atoms from two different 9-hydroxy-fluorene-9-carboxylate ligands, two pyridine nitrogen atoms and two ethanol oxygen atoms, forming a distorted octahedral coordination geometry. The extensive O–H···O hydrogen bonding connects the molecules to form a one-dimensional chain structure. Between adjacent one-dimensional chains, a two-dimensional layered structure was formed by fluorene ring π-π packing interaction. Between the layers, a three-dimensional structure was formed through the π-π packing interaction of the pyridine ring. Moreover, the thermal stability and photoluminescent property of the complex has been investigated.

关键词： 9-hydroxy-fluorene-9-carboxylic acid synthesis crystal structure

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Supplier selection based on intuitionistic fuzzy sets and analytic hierarchy process

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ICIC Express Letters, Part B: Applications 2015年第2期6卷 411-416页

作者： Xiang, Yu Zhang, Xiaoge Wei, Daijun Key Laboratory of Biologic Resources Protection and Utilization of Hubei Province Hubei University for Nationalities No. 39 Xueyuan Road Enshi China School of Science Hubei University for Nationalities No. 39 Xueyuan Road Enshi China School of Computer and Information Science Southwest University No. 2 Tiansheng Road Beibei District Chongqing China

Supplier selection problem is an open issue concerned by many researchers. So far, many methods have been proposed to deal with this problem, such as analytic hierarchy process (AHP), and Dempster-Shafer theory (DST). However, how to represent the incomplete information in the supplier selection problem is still a meaningful issue. In this paper, we propose a novel approach, which combines intuitionistic fuzzy sets (IFS) with analytic hierarchy process. The presented method consists of two parts. One is to employ AHP to determine the weight for each criterion. The other is to make full use of IFS to express the uncertain information in this problem. The main contribution of this paper is to employ the neutral measure to combine the membership degree and non-membership degree in each IFS. By this way, these two degrees can be aggregated. Finally, a case study is used to demonstrate the efficiency of the proposed method. © 2015, ICIC International.

关键词： Analytic hierarchy process

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