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1.
Propyl O-(α-L-rhamncpyranosyl)-(1→3)-[2,4-di-O-(2s-methylbutyryl)-α-L-rham-nopyranosyl]-(1→2)-(3-O-acetyl-β-D-glucopyranosyl)-(1→2)-β-D-fucopyranoside (1), the tetrasac-charide moiety of Tricolorin A, was synthesized in total 23 steps with a longest linear sequence of 10 steps, and overall yield of 3.7% from D-Glucose. The isomerization of the dioxolane-type berzyli-dene in the presence of NIS/AgOTf was observed. Tetrasaccharide 1 exhibited no activity against the cultured P388 cell as Tricolorin A did.  相似文献   

2.
Thetriazenereagentswereusedf0rthedeterminationofcadmium,mercuryandzinc.Somereagentscontainingdiaz0amin0az0benzenehavebeenreported'-'.Wehavesynthesizedreagentscontainingdiaz0aminonitrobenzene4'5.Recently,anewreagentNBTNPThasbeensynthesizedin0urlab0ratoryanditscolorreactionwithcadmiumwasstudied.Resultsshowthatthisreagenthashighsensitivitywithmetallicions.Theproposedmeth0dhasbeenaPpliedt0thedeterminati0nofcadmiuminhumanhairandwastewaterwithsatisfact0ryresults.Theprocedureofsynthesis0fNBTNPT…  相似文献   

3.
Shikonin 1 was a key component isolated from the traditional Chinese herbal medicine, Zicao(Lithospermum erythrorhizon Sieb.et Zucc), which possesses multiple biological activities1. There have been many synthetic routes to shikonin, however, all these ro…  相似文献   

4.
Diarylheptanoidsconstituteadistinctgroupofmetabolitesofnaturalplantcharacterizedbytwoaromaticringslinkedbyalinearsevenaliphaticchain.Therehavebeenfewreportsonthebiologicalactivitiesofdiarylheptanoids,mostofwhichappearingintheareasofanti-inflammatory,anti-oxidative,superoxidescavengingandanti-hepatotoxiceffects1,2.SomeofthemareusedastraditionalmedicineinAsia3.Compound1and2werefirstlyisolatedfromtherhizomesofZingiberofficalrespectively4,5.Sofarthesynthesisofthesetwocompoundshavenotbeenreportedy…  相似文献   

5.
The title compound (C40H42N2) has been synthesized by the reaction of 1-(1-naphthyl)-1-phenyl-3-chloropropylene and bis(4-(diethylamino) phenyl)methanone, and characterized by IR, 1H NMR, MS and X-ray diffraction analysis. The crystal belongs to the monoclinic system, space group P21/c with a = 17.047(3), b = 10.807(2), c = 1&494(4) (A), β = 105.727(4)°, V=3279.4(11) A3, Mr = 550.76, Z = 4, Dc = 1.115 g/cm3, μ(MoKα) = 0.085 mm-1, F(000) = 1184, the final R = 0.0625 and wR = 0.1384 for 2276 observed reflections (I > 2σ(Ⅰ)). X-ray analysis reveals that the butadiene fragment adopts a planar cisiod conformation and makes a dihedral angel of 69.4(2)° with the naphthalene ring.  相似文献   

6.
7.
Copper(Ⅱ) resorcylic acid(CuRes) nanoparticles were synthesized by using reactive precipitation method with resorcylic acid and blue copperas as the raw material in a rotating packed bed. The sample obtained was characterized by using X-ray diffraction( XRD), transmission electron microscopy( TEM ), Fourier transform infrared spectroscopy (FTIR), thermo-gravimetric analyses (TG), and element analysis. In addition, the catalytic activity of CuRes nanoparticles on the thermal decomposition of nitrocellulose-nitroglycerine (NC-NG) was also determined via DSC.The results show that the spherical nanoparticles with a diameter of 20 nm were obtained in ethanol solution. The peak temperature of the thermal decomposition of NC-NG-CuRes decreases by 3 ℃ compared with that of normal CuRes,and the decomposition enthalpy is increased by 735 J/g, and therefore, it is reasonable to assume that CuRes nanoparticles have a better catalytic activity.  相似文献   

8.
(±)-13-Hydroxy-8 (14)-abietene, a rare alicyclic diterpene possessing an isopropyl group and a hydroxy group at the C-13 position, was isolated from Solidago missouriensis nutt1. Many diterpenes exhibit significant bioactivities, such as antibacterial. As a part of our synthetic studies on the naturally-occurring diterpenes, we are attemping the synthesis of the rare natural compound. To our knowledge no total synthetic work has been reported yet. In order to study the further relationship b…  相似文献   

9.
A convenient synthesis of cis-(±) isomer 1 and trans-(±) isomer 2 of lamivudine starting from benzoyloxyacetaldehyde and l,4-dithiane-2,5-diol is described. The key steps include chlorination of oxathiolane lactol 5 by SOCl2/DMF, followed by coupling with silylated N4-acetylcytosine and deprotection. The overall yield was 42.6 % and 20.1 %, respectively.  相似文献   

10.
α-{3-[2-hydroxy-3-(N-methyl-N-hydroxyethylamino)propoxy]propyl}-ω-butylpolydimethylsiloxanes Ⅲ with various moleculax weights were prepared by epoxy addition of α-[3-(2,3-epoxy-propoxy)propyl]-ω-butylpolydimethylsiloxanes Ⅱ and Nmethylmonoethanolamine.At each step.the outcome compounds were characterized through FT-IR and NMR spectra,the results showed that each step was successfully carried out and objective products were achieved.  相似文献   

11.
以浓硫酸为催化剂,氨基硫脲(1)与二元羧酸(2a~2d)在微波辐射下经环合反应合成了四种新型的1,ω-二(2,2-二氨基-1,3,4-噻二唑-5-)烷烃类化合物,其结构经1H NMR和IR表征.最佳反应条件为:1 20mmol,n(1):n(2)=2.0:1.8,浓硫酸2.6 mL,中低火微波辐射6 min,产率77....  相似文献   

12.
Total Synthesis of (±)-Calanolide A and Its Anti-HIV Activity   总被引:1,自引:0,他引:1  
  相似文献   

13.
Chrysotricine1wasisolatedfromtheChineseherbmedicineHedyotiSChrysotricha'anditssthectUrehasbeenestablishedasanew0-carbolinealkaloidwitha2,5-trans-substitutedtetrahydrofuranylgrouPatitsl-positionbyX-raydiffractionandspectralanalysis.PharmaceuticalstUdiesshowedpotentialantitUmoractivity.Theinterestingbiologicalactivityandthechemistryof6-carb0linesmict[JIehaveattiactedconsiderableattentioninrecentyears.InordertostUdythisstrUctUre-activityrelationshiPfurther,wewereillterestedinthedevelopmento…  相似文献   

14.
The substitution/adsorption structures of Co on an anatase TiO2 (001)-(1×4) surface are investigated using the DFT/local density approximation (LDA) method.Theoretical calculation shows that the Co ion prefers to be adsorbed on the surface of anatase TiO2.The density of states (DOS) analysis finds that the Co 3d is located mainly in the energy gap region.The Co 3d partial density of states (PDOS) indicates that there is a substantial degree of hybridization between O 2s and Co 3d in valence band (VB) regions in the substitution models.The conclusion is that the mode of substitution is more active when the catalyst is a higher-energy surface.  相似文献   

15.
1 INTRODUCTION The transition metal complexes containing ferrocene ligand arouse the interest of chemists because of their novel structures and special properties[1]. The ferrocene derivatives have been used in electrochemistry, in nonlinear optics, and as molecular ferromagnets. Some complexes of 1,1′-bis(diphenylphosphino)ferrocene (dppf) have been synthesized, and many of their crystal structures have been reported by far[2~5]. Here we report the synthesis and crystal structure of a …  相似文献   

16.
Chrysotricine 1 was isolated from the Chinese herb medicine Hedyotis Chrysotricha and was shown to possess antitumor activity1. Its structure has been elucidated as a novel zwitterionic (-carboline alkaloid containing a 2,2,5-trisubstituted tetrahydrofuranyl group. The (-carboline compounds have attracted considerable attraction in recent years because of their promising and intriguing biological activities2. Recently, we have established the absolute configuration of chrysotricine by the fir…  相似文献   

17.
1 INTRODUCTION Many crown ethers have been synthesized[1, 2] and widely used[3~5]. The amide-type acyclic poly- ethers with versatile molecular structures offer many advantages over the traditional crown ethers, such as their potential activity for ion-selective electrodes[6] and the extraction of metal ions[7], so they have attracted much scientific attention[8~10]. In an effort to investigate the effect of skeleton of acyclic polyether on the extractability of metal ions, and to find …  相似文献   

18.
2-苯基-1-(4-(1-吡咯乙氧基)苯基)乙酮是合成抗骨质疏松药拉索昔芬重要的结构片段。以苯酚为原料经成醚,磺酰氯酯化得到磺酸酯,然后经亲核取代反应,傅-克酰基化反应高收率地合成了目标化合物,其结构通过NMR和HRMS进行了表征。  相似文献   

19.
MThekeymaterials,5-amino-l,10-phenanthrolineandetS-Ru(phew,CI,,werepreparedbythemethodsofreferences"'.Synthesisofla,foandicEquimolaramountsofcorrespondingto-bromo-alkyIacyIohIondewasaddeddropwisetoasuspensionof5-amino-l,10-phenanthrolineandsodiumdicarbonateindryacetonitrilewithstirringatroomtemperatureundernitrogenfor4-6hours.Thentheresultingsolidwasfilteredandwashedbyacetonitrile,5%sodiumbicarbonateaqueoussolutionandwaterinturn.Afterbeingdriedicvacuo,yellowmicrocrystalsla-cwereobtained.Sy…  相似文献   

20.
陈顺玉  杨娥  张健 《结构化学》2013,32(1):149-153
A new Zn(Ⅱ) coordination polymer [Zn3(btec)(OH)2(H2O)2]n (1, btec = 1,2,4,5- benzenetetracarboxylate) has been synthesized by hydrothermal reaction and its structure was determined by single-crystal X-ray diffraction analysis. The title compound crystallizes in mono- clinic, space group C2/c, with a = 19.580(3), b = 5.0137(8), c = 15.975(3), β = 121.629(2)°, V = 1335.3(4)3, C10H8O12Zn3, Mr = 516.27, Z = 4, Dc = 2.568g/cm3, μ = 5.419 mm-1, F(000) = 1016, R = 0.0590 and Rw = 0.1279 for 1110 observed reflections (I > 2σ(I)). X-ray analysis shows that the asymmetric unit of the title compound contains two crystallographically unique Zn(Ⅱ) atoms which are connected through the bridging carboxylate oxygen atoms of the btec ligands and μ2-bridging oxygen atoms of water molecules to generate an infinite one-dimensional chain. The adjacent chains are linked together through the benzene rings of the btec ligands to form a two-dimensional polymeric network. The adjacent two-dimensional layers are further connected together by the benzene rings of btec ligands to give the final three-dimensional structure. The benzene rings act as pillars between two layers.  相似文献   

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