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Geranyl phenyl ethers from Illicium micranthum and their anti-HBV activity

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Chinese Journal of Natural Medicines 2022年第2期20卷 139-147页

作者： LIU Yu YOU Yun-Xia RAO Li HE Qian SU Yu FAN Yue LI Yi-Zhou XU You-Kai ZHANG Chuan-Rui Chongqing Key Laboratory of Natural Product Synthesis and Drug Research and Chemical Biology Research CenterSchool of Pharmaceutical SciencesChongqing UniversityChongqing 401331China Key Laboratory of Tropical Plant Resource and Sustainable Use Xishuangbanna Tropical Botanical GardenChinese Academy of SciencesMenglun 666303China State Key Laboratory of Drug Research Shanghai Institute of Materia MedicaChinese Academy of SciencesShanghai 201203China

Fourteen new geranyl phenyl ethers(1–14)along with three known compounds(15–17)were isolated from Illicium micranthum,and their structures were elucidated by comprehensive spectroscopic *** A–H(1–8)were characterized as geranyl vanillin ethers,while 9 and 10 were dimethyl acetal *** I and J(11 and 12)were rare geranyl isoeugenol *** K and L(13 and 14)represented the first example of geranyl guaiacylacetone ether and geranyl zingerone ether,*** 1,2 and 15 exhibited anti-HBV(hepatitis B virus)activity against HBsAg(hepatitis B surface antigen)and HBeAg(hepatitis B e antigen)secretion,and HBV DNA replication.

关键词： Illicium micranthum Geranyl phenyl ethers spectroscopic data Anti-HBV activity

Theoretical Study on the Low-Lying Electronic States of He_2,He_2^+,and He_2^(++)

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Communications in Theoretical Physics 2012年第6期57卷 1048-1052页

作者：张云光查新未高涛 School of Science Xi'an Institute of Posts and Telecommunications Insititute of Atomic and Molecular Physics Sichuan University

The equilibrium geometries, potential energy curves, spectroscopic dissociation energies of the ground and low-lying electronic states of He2, He2^＋ and He2^＋＋ are calculated using symmetry adapted cluster/symmetry adapted cluster-configuration interaction （SAC/SAC-CI） method with the basis sets CC-PV5Z. The corresponding dissociation limits for all states are derived based on atomic and molecular reaction statics. The analytical potential energy functions of these states are fitted with Murrell-Sorbie potential energy function from our calculation results. The spectroscopic constants Be, αe, ωe, and ωeχe of these states are calculated through the relationship between spectroscopic data and analytical energy function, which are in well agreement with the experimental data. In addition, the origin of the energy barrier in the ground state X^I∑9^＋ of He2^＋＋ energy curve are explained using the avoided crossing rules of valence bond model.

关键词： potential energy curve spectroscopic data Murrell-Sorbie function

Ab initio calculations on the α^3∑u^＋ state properties of dimer ^7Li2

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Chinese Physics B 2007年第9期16卷 2701-2708页

作者：施德恒孙金锋朱遵略刘玉芳 College of Physics & Electronic Engineering Xinyang Normal University Xinyang 464000 China College of Physics & Information Engineering Henan Normal University Xinxiang 453007 China

The comparison between single-point energy scanning （SPES） and geometry optimization （OPT） in determining the equilibrium geometry of the α^3∑u^＋ state for ^7Li2 is made at numerous basis sets such as 6-311＋＋G（2df）, cc-PVTZ, 6-311＋＋G（2df, p）, 6-311G（3df,3pd）, 6-311＋＋G（2df,2pd）, D95（3df,3pd）, 6-311＋＋G, DGDZVP, 6-311＋＋G（3df,2pd）, 6-311G（2df,2pd）, D95V＋＋, CEP-121G, 6-311＋＋G（d,p）, 6-311＋＋G（2df, pd） and 6-311＋＋G（3df,3pd） in full active space using a symmetry-adapted-cluster/ symmetry-adapted-cluster configuration-interaction （SAC/SAC=CI） method presented in Gaussian03 program package. The difference of the equilibrium geometries obtained by SPES and by OPT is reported. Analyses show that the results obtained by SPES are more reasonable than those obtained by OPT. We have calculated the complete potential energy curves at those sets over a wide internuclear distance range from about 3.0α0 to 37.0α0, and the conclusion is that the basis set cc-PVTZ is the most suitable one. With the potential obtained at ccopVTZ, the spectroscopic data （Te, De, D0, ωe,ωeХe, αe and Be） are computed and they are 1.006 eV, 338.71 cm^-1, 307.12 cm^-1, 64.88 cm^-1, 3.41 cm^-1, 0.0187 cm^-1 and 0.279 cm^-1, respectively, which are in good agreement with recent measurements. The total 11 vibrational states are found at J=0. Their corresponding vibrational levels and classical turning points are computed and compared with available RKR data, and good agreement is found. One inertial rotation constant （By） and six centrifugal distortion constants （Dr Hv, Lv, My, Nv, and Ov） are calculated. The scattering length is calculated to be -27.138α0, which is in good accord with the experimental data.

关键词： ab initio potential energy curve spectroscopic data vibrational state scattering length

New analytical potential energy function for doubly charged diatomic molecules

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Chinese Physics B 2005年第2期14卷 317-322页

作者：王藩侯杨传路朱正和经福谦 InstituteofComputationalPhysics YibinUniversityYibin644007China YantaiNormalUniversity Yantai264000China InstituteofAtomicandMolecularPhysics SichuanUniversityChengdu610003China SouthwestInstituteofFluidPhysics Mianyang621900China

A new analytical potential function for doubly charged diatomic ions is proposed as V(R)=(∑k n=0anRn-1)exp(-ak+1R)+C/R,where an, ak+1 and C are parameters, and R is the nuclear distance. This function can be used to describe the potential curves for doubly charged diatomic ions with both potential minimum and maximum, or without any stationary point. As examples, potential functions of this form for ground states of BH2+, He22+ and HF2+ have been *** calculations using the theoretical method QCISD with basis set 6-311++G* have shown that the potential minimum of BH2+is at Rmin=0.147nm, the maximum at Rmax=0.185nm, and ΔE = Emax - Emin=0.062 eV; for He22+Rmin=0.0736nm, Rmax=0.105nm, and ΔE = Emax - Emin=0.71 eV. It is found that the potential curve for HF2+ is one with a singly repulsive branch. The force constants and spectroscopic data for BH2+ and He22+ have also been worked out.

关键词： potential energy function dication dissociation limit spectroscopic data

Characterization of Chemical Constituents of Luffa operculata(Cucurbitaceae)

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American Journal of Analytical Chemistry 2011年第8期2卷 989-995页

作者： Cleia Rocha de Sousa Feitosa Roberio Costa da Silva Raimundo Braz-Filho Jane Eire Silva Alencar de Menezes Sonia Maria Costa Siqueira Francisco Jose Queiroz Monte Programa de Pos-Graduacao em Quimica-DQOI-CC Universidade Federal do CearaFortalezaBrazil Universidade Estadual do Norte Fluminense Darcy Ribeiro Campos dos GoytacazesBrazil Universidade Estadual do Ceara Faculdades de Educacao de CrateusFortalezaBrazil Universidade Estadual do Ceara Itapipoca FortalezaBrazil Universidade Estadual do Ceara e campos do ItaperiFortalezaBrazil

A mixture of new ceramides (1, 2, 3, 4 and 5) together with a binary mixture of ceramides with long chain alkyl (6 and 7), triterpenoid (10) and steroids (11 and 12) have been isolated from bark of the fruits and of the stems of Luffa operculata (Cucurbitaceae). The structures were elucidated by comprehensive spectro- scopic analysis including 1H and 13C NMR, DEPT (distortionless enhancement by polarization transfer), COSY (correlated spectroscopy), HMQC (heteronuclear multiple quantum coherence), HMBC (heteronu- clear multiple bond connectivity), IR (infrared), HR-ESI-MS (electrospray ionization-high resolution mass spectra) and LR-MS (low resolution electron ionization mass spectra) experiments. All the ceramides are reported for the first time in Cucurbitaceae and this is the first report of the rare triterpene 10 isolated from Luffa operculata. The ceramides 6 and 7 showed a high acetylcholine esterase inhibitory effect.

关键词： Cucurbitaceae Ceramides Triterpenes spectroscopic data

First Total Synthesis of A New 5-Deoxyflavone

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有机化学 2003年第Z1期23卷 303-303页

作者： LU Jia-Wen GAO Jin-Ming College of Life Sciences Northwest Sci-Tech University of Agriculture and Forestry Yangling 712100 College of Life Sciences Northwest Sci-Tech University of Agriculture and Forestry Yangling 712100 National Engineering Research Center for Phytochemistry in West China Yangling 712100

　　A novel 5-deoxyflavone compound, 7, 8-dimethoxy-3′, 4′-methylene-dioxyflavone (1), was in 2002 isolated from the root bark of Albizia Odoratissima. [1] The compound 1 was preparaed from pyrogallic acid (2) and piperonal(5) in four steps (Scheme 1). [2] The spectroscopic data (1H NMR, 13C NMR, MS and IR) of 1 were in good agreement with those of natural product. [ 1]……

关键词： spectroscopic data natural product root bark