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Journal of Integrative Plant Biology 2008年第12期50卷 1499-1507页

作者： Xia Hao Jie Qian Shan Xu xin song jian Zhu School of Life Science and Technology Tongji University Shanghai 200092 China

The casepase is considered to regulate the process of programmed cell death in the development of organisms. In this study, caspase 3-like protease was detected by immunohistochemistry and immunoelectron microscopy during the development of sieve element and tracheary element of stem in Cucurbita moschata Duch. Antibody with brown color （under light microscopy） and gold particles （under transmission electron microscopy） for detecting caspase 3-like protease was mainly displayed in inner phloem, external phloem and xylem in the region close to procambium. From the results it was considered that caspase 3-like protease did exist in vascular elements and played different roles during the development of sieve and tracheary elements, and different types of programmed cell death might be carried out. The caspase 3-like protease mainly participated in making cytoplasmic streaming cease and in degrading P-protein bodies; however, it rarely participated in the function for signal transferring in the developmental sieve element. However, it might induce calcium accumulation for rupturing the tonoplast in the signal of PCD in the developmental tracheary element.

关键词： caspase 3-like protease Cucurbita moschata immunoelectron microscopy P-protein bodies programmed cell death.

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

Synthesis, Crystal Structure and Antitumor Activity of 3,3-(1,4-Phenylene)-bisfuro[3,2-d]pyrimidin-4(3H)-ones

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Chinese Journal of Structural Chemistry 2019年第6期38卷 918-922页

作者： HUANG Sheng-Tian HU Yang-Gen song xin-jian College of Chemistry and Environmental Engineering Sichuan University of Science and EngineeringZigong 643000China College of Pharmacy and Institute of Medicinal Chemistry Hubei University of MedicineShiyan 442000China

3,3-（1,4-Phenylene）-bis(polysubstituted furo[3,2-d]pyrimidin-4（3 H）-ones 3 were synthesized from the starting material of functionalized iminophosphorane 1 by aza-Wittig reaction. All of the title compounds were characterized by 1H NMR, MS and elemental analysis. Meanwhile, the single crystal of compound 3 c, C46H68N6O10, was also obtained and determined by X-ray crystallography. Crystal data: triclinic, space group P1, a = 9.0017（3）, b = 10.5908（4）, c = 14.0116（5） ?, α = 108.582（2）°, β = 94.296（1）°, γ = 105.059（2）°, V = 1204.40（7） ?3, Z = 1, F（000） = 466, Dc = 1.193 g/cm3, μ = 0.084 mm-1, R = 0.0998 and wR = 0.2146 for 4213 independent reflections（Rint = 0.0689） and 2796 observed ones（I > 2σ（I））. The in vitro antitumor activities of compounds 3 a～3 c were preliminarily evaluated by the standard MTT assay.

关键词： furo[3,2-d]pyrimidinone synthesis crystal structure antitumor activity

Computational Insights into the Excited State Intramolecular Proton Transfer Reactions in Ortho-hydroxylated Oxazolines

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Chinese Journal of Structural Chemistry 2021年第5期40卷 540-548,527页

作者： LIU Gai-Mei MA Wei-Jia WANG Yan YANG Yan song xin-jian School of Chemistry and Environmental Engineering Hubei Minzu UniversityEnshi 445000China Key Laboratory of Magnetic Resonance in Biological Systems National Center for Magnetic Resonance in WuhanState Key Laboratory of Magnetic Resonance and Atomic and Molecular PhysicsWuhan Institute of Physics and MathematicsChinese Academy of SciencesWuhan 430071China

Excited-state intramolecular proton transfer(ESIPT) reactions of three ortho-hydroxylated oxazolines, 2-(4,4-dimethyl-4,5-dihydro-oxazol-2-yl)-phenol(DDOP), 4-(4,4-dimethyl-4,5-dihydro-oxazol-2-yl)-[1,1?-biphenyl]-3-ol(DDOP-C_(6)H_(5)) and 4-(4,4-dimethyl-4,5-dihydrooxazol-2-yl)-3-hydroxy-benzonitrile(DDOP-CN), have been systematically explored by density functional theory(DFT) and time-dependent density functional theory(TDDFT) methods. Two stable configurations(enol and keto forms) are found in the ground states(S_(0)) for all the compounds while the enol form only exists in the first excited states(S_(1)) for the compound modified with electron donating group(-C_(6)H_(5)). In addition, the calculated absorption and emission spectra of the compounds are in good agreements with the experiments. Infrared vibrational spectra at the hydrogen bond groups demonstrate that the intramolecular hydrogen bond O(1)-H(2)···N(3) in DDOP-C_(6)H_(5) is strengthened in the S_(1) states, while the frontier molecular orbitals further reveal that the ESIPT reactions are more likely to occur in the S_(1) states for all the compounds. Besides, the proton transfer potential energy curves show that the enol forms can barely convert into keto forms in the S_(0) states because of the high energy barriers. Meanwhile, intramolecular proton transfer of all the compounds could occur in S_(1) states. The ESIPT reactions of the ortho-hydroxylated oxazolines are barrierless processes for unsubstituted DDOP and electron withdrawing substituted DDOP-CN, while the electron donating substituted DDOP-C_(6)H_(5) has a small barrier, so the electron donating is unfavorable to the ESIPT reactions of ortho-hydroxylated oxazolines.

关键词： excited-state intramolecular proton transfer electron donating group ortho-hydroxylated oxazolines potential energy curves

Syntheses, Crystal Structures and Hydrogen-bonding Motif of Two Glycoluril Derivatives

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Chinese Journal of Structural Chemistry 2019年第5期38卷 754-760,669页

作者： LIU Xue-Mei WANG Dong-Hua song xin-jian WANG Jun-Gang Key Laboratory of Biologic Resources Protection and Utilization of Hubei Province Hubei University for Nationalities Enshi 445000 China School of Chemical Engineering Guizhou Minzu University Guiyang 550025 China

The synthesis and aggregation behavior of two glycoluril derivatives were *** crystal of compound 1 belongs to the triclinic system,space group ■,with a=8.946（1）,b=13.445（2）,c=20.361（3）?,α=89.517（3）,β=84.405（3）,γ=86.325（3）°,Z=2,V=2432.1（6）?3,Dc=1.293 g·cm-3,C48H34N6O6·2DMSO,Mr=947.07,F（000）=992,μ=0.170 mm-1,the final R=0.1606 and wR=0.2410 for 4382 observed reflections（Ⅰ>2σ（Ⅰ））.The crystal of compound 2belongs to the monoclinic system,space group P21/c,with a=9.500（3）,b=24.522（8）,c=17.997（6）?,Z=2,V=4054（2）?3,Dc=1.296 g·cm-3,C48H34N6O6,Mr=790.81,F（000）=1648,μ=0.087mm-1,the final R=0.2146 and wR=0.2535 for 2878 observed reflections（Ⅰ>2σ（Ⅰ））.Unlike the highly conserved R22（8）hydrogen-bonding amide···amide homosynthon,the structural analysis indicated that compound 1 selected the C（20）hydrogen-bonding motif and 2 selected the R22（34）hydrogen-bonding motif,which revealed the competition from remote solvent molecule and the interference of the molecular hydrocarbon core in crystal *** supramolecular structure revealed molecule 1 is further linked into a one-dimensional chain and 2 into a two-dimensional interwoven plane by N–H···N hydrogen bonds.

关键词： hydrogen bond glycoluril supramolecuclar synthons crystal engineering

Synthesis, Crystal Structure and Antitumor Activity of N-(5-Aryl-1,3,4-thiadiazol-2-yl)-N?-((E)-styryl)ureas

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Chinese Journal of Structural Chemistry 2019年第7期38卷 1086-1092页

作者： song xin-jian WANG Xu-Mei SUN Qi HUANG Sheng-Tian WANG Yan College of Chemistry and Environmental Engineering Sichuan University of Science and Engineering Zigong 643000 China School of Chemical and Environmental Engineering Hubei University for Nationalities Enshi 445000 China

N-(5-Aryl-1,3,4-thiadiazol-2-yl)-N?-((E)-styryl)ureas 4 a～4 i were designed and synthesized as antitumor agents, and their structures were characterized by IR, 1 H NMR, 13 C NMR,MS and elemental analysis. The single crystal of compound 4 a, C17 H13 FN4 OS, was also determined by X-ray crystallography. Crystal data: monoclinic, space group P21/n, a = 4.9401(8), b= 8.7100(15), c = 36.604(6) ?, β = 93.320(3)°, V = 1572.4(5) ?3, Z = 4, F(000) = 704, Dc = 1.438 g/cm3, μ = 0.228 mm-1, R = 0.0600 and wR = 0.1448 for 2743 independent reflections(Rint =0.0418) and 2174 observed ones(I > 2σ(I)). The in vitro antitumor activities of compounds 4 a～4 i were preliminarily evaluated by the standard MTT assay.

关键词： 1,3,4-thiadiazole urea crystal structure antitumor activity

Synthesis, Crystal Structure and Antitumor Activity of 4-(5-(2,6-Difluorophenyl)-1,3,4-oxadiazol-2-ylthio)-2-(trifluoromethyl)thieno[2,3-d]pyrimidine

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Chinese Journal of Structural Chemistry 2019年第8期38卷 1344-1348页

作者： song xin-jian LI Chen-Chen WANG Xu-Mei SUN Qi YANG Ping School of Chemical and Environmental Engineering Hubei University for NationalitiesEnshi 445000China College of Chemistry and Environmental Engineering Sichuan University of Science and EngineeringZigong 643000China

The title compound 4-(5-(2,6-difluorophenyl)-1,3,4-oxadiazol-2-ylthio)-2-(trifluoromethyl)thieno[2,3-d]pyrimidine(C15H5F5N4OS2, Mr = 416.35) was designed and synthesized as antitumor agent, and its structure was determined by 1H NMR, 13C NMR, MS, elemental analysis and single-crystal X-ray diffraction. The crystal belongs to monoclinic system, space group P21/c with a = 9.904(2), b = 10.057(2), c = 16.595(3) ?, β = 100.000(3)°, V = 1627.9(6) ?3, Z = 4, F(000) = 832, Dc = 1.699 g/cm3, μ = 0.395 mm-1, R = 0.0468 and wR = 0.1255 for 4726 independent reflections(Rint = 0.0336) and 2847 observed ones(I > 2σ(I)). The in vitro antitumor activity of the title compound was preliminarily evaluated by the standard MTT assay.

关键词： thieno[2,3-d]pyrimidine 1,3,4-oxadiazole fluorinated compound crystal structure antitumor activity

Rotary self-locking intramedullary nail for long tubular bone fractures

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Chinese Medical Journal 2013年第20期126卷 3874-3878页

作者： Huang Zhong-lian Yang Hai-long Xu jian-kun Xia Xue Wang xin-jia song jian-xin Hu Jun Shantou Univ Med Coll Affiliated Hosp 1 Dept Orthoped Surg Shantou 515041 Guangdong Peoples R China Shantou Univ Med Coll Affiliated Hosp 2 Dept Orthoped Surg Shantou 515041 Guangdong Peoples R China

Background Intramedullary nails had been widely used in the treatment of long-bone fractures because of less interference of fractures and center bearing biomechanical advantage. However, it had been also found many shortcomings such as broken nails, delayed healing and was modified in order to achieve better efficacy and reduce complications. The aim of the present study is to compare the efficacy of rotary self-locking intramedullary nails （RSIN） with that of interlocking intramedullary nails （IIN） in the treatment of long-bone fractures.

关键词： rotary self-locking intramedullary nail (RSIN) fracture," long bone," fracture healing

Control of Perceptual Image Quality Based on PID for Streaming Video

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The Journal of China Universities of Posts and Telecommunications 2003年第4期10卷 82-89页

作者： song jian-xin(Information Engineering Department, Nanjing University of Posts & Telecommunications, Nanjing 210003, P.R. China) Information Engineering Department Nanjing University of Posts & Telecommunications Nanjing 210003

Constant levels of perceptual quality of streaming video is what ideall usersexpect. In most cases, however, they receive time-varying levels of quality of video. In thispaper, the author proposes a new control method of perceptual quality in variable bit rate videoencoding for streaming video. The image quality calculation based on the perception of human visualsystems is presented . Quantization properties of DCT coefficients are analyzed to controleffectively. Quantization scale factors are ascertained based on the visual mask effect. AProportional Integral Difference (PID) controller is used to control the image quality. Experimentalresults show that this method improves the perceptual quality uniformity of encoded video.

关键词： video coding perceptual image quality image quality metric image qualitycontrol

Genetic Improvement and Biological Characteristic Analysis of Dwarf Abortive TypeJaponicaCMS Lines with Wide Compatibility

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Agricultural Science & Technology 2011年第7期12卷 980-984,996页

作者： song xin-wei LIN jian-rong WU Ming-guo State Key Laboratory of Rice Biology China National Rice Research Institute Hangzhou 310006

From the view of methodology for genetic improvement ofJaponicacytoplasmic male sterile(CMS) lines,we introduced the breeding process of the dwarf-abortive type(DA type)JaponicaCMS line Chunjiang 95A with wide compatibility,and further investigated the biological characteristics of the DA type Chunjiang 95A and its isonuclear alloplasmic CMS line Dian-I type Chunjiang *** results show that DA type Chunjiang 95A is a japonicalinous CMS line and mainly typical abortive,which is better in fertility stability than stained abortive typeJaponica CMS *** DA type Chunjiang 95A is featured with high stigma exsertion,good flowering habit,high outcrossing rate and wide *** recoverability differs from stained abortive typeJaponicaCMS ***,we discussed genetic improvement of the typical abortive type JaponicaCMS lines and the application prospects of heterosis.

关键词： Wide compatibility Japonica rice CMS line Stigma exsertion Breeding