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1.
ChemicalStudiesontheGlycosidesintheLeavesofOplopanaxElatusNakai(Ⅳ)*WANGGuang-shuandXUJing-da(NormanBethuneUniversityofMedical...  相似文献   

2.
Two new spirostanol glycosides named agamenoside A and B, ere isolated from the fermented leaves of Agave americana. Their structures were elucidated as (23S,25R)-5α-spirostan-3β,6α,23-triol 3-O-α-L-rhamnopyranosyl-(1→3)-β-D-glucopyranosyl-(1→2)-[β-D-xylopyranosyl-(1→3)]-β-D-glucopyranosyl-(1→4)-β-D-galactopyranoside(1) and (25R)-5α-spiro-stan-3β,6α-diol 3-O-β-D-glucopyranosyl-(1→2)-[β-D-xylopyranosyl-(1→3)]-β-D-glucopyra-nosyl-(1→4)-β-D-galactopyranoside(2) by a combination of chemical and spectral methods.  相似文献   

3.
In our previous studies on the actinomycete resources in Yunnan Province, we found some strains with potential bioactivities. Streptomyces autolyticus JX-47, a strain producing broad-spectrum antiviral metabolites was studied. A new compound autolytimycin 1, together with the other two known compounds, lebstatin 21 and 17-O-demethyl-geldanamycin 32,3, were isolated from the culture broth. The structure of autolytimycin was determined by spectral evidence, and shown to be similar to geldanam…  相似文献   

4.
Two New Glycosides from the Roots of Ranunculus ternatus   总被引:2,自引:0,他引:2  
Two new glycosides named as ternatoside A 1 and ternatoside B 2 were isolated from the roots of Ranunculus ternatus, the structures were determined by 1D and 2D NMR, ESI-MS techniques, and chemical methods.  相似文献   

5.
Due to their special chemical structure, tetraether lipids (TEL) represent essential elements of archaeal membranes, providing these organisms with extraordinary properties. Here we describe the characterization of a newly isolated structural element of the main lipids. The TEL fragment GDNT-β-Glu was isolated from Sulfolobus metallicus and characterized in terms of its chemical structure by NMR- and MS-investigations. The obtained data are dissimilar to analogically derived established structures – in essence, the binding relationships in the polar head group are re-determined and verified. With this work, we provide an important contribution to the structure elucidation of intact TEL also contained in other Sulfolobus strains such as Solfulobus acidocaldarius and Sulfolobus solfataricus.  相似文献   

6.
Two new phenolic glycosides,everninic acid methyl ester-2-O-β-O-xylopyran-osyl-(1→6)-β-D-glucopyranoside 1 and 7-hydroxyl-5-methoxyphthalide-7-β-D-xylopyranosyl-(1→6)-β-D-glucopyranoside 2 were isolated from the roots of Rhododendron molle G.Don. Their structures were determined by spectral evidence including 2D NMR techniques.  相似文献   

7.
Broussonetia kazinoki Sieb (Moraceae) is distributed throughout China and Japan. Previous investigations of this plant revealed the presence of isoprenylated flavans, isoprenylated flavonoids, isoprenylated 1,3-diphenylpropanes1 and alkaloids2,3. Natural prenylated flavonoids have shown potent inhibition against human hepatoma PLC/PRF/5 and epidermoid carcinoma KB cells in vitro4. In order to search for its biologically active compounds, chemical study on this plant was carried out and le…  相似文献   

8.
The leaves of Eriobotrya japonica (Thunb.) Lindl (Rosaceae) have been widely used as a folk medicine (known as “Pipaye”) to treat stomachache and promote antitussive, anti-inflammatory and diuretic effects in China. A number of triterpenoids1,2, sesquit…  相似文献   

9.
1 INTRODUCTION In recent years many efforts have been devoted to the preparation and characterization of pendant- arm macrocyclic complexes due to the fact that the ligating groups attached to the macrocyclic skeleton can offer additional donor groups to maintain the coordination sphere of metals in the macrocycles[1~7]. In this way, functionalized pendant arm macrocyc- lic complexes have been designed and prepared so as to mimic the structures and properties of certain metalloenzymes and…  相似文献   

10.
A new taxoid, 2-deacetyl-2α, 14β-dihydroxybaccatin Ⅳ (1), was isolated from the leaves and branches of Taxus chinensis together with the known compound baccatin Ⅳ (2). The structure of the new compound was elucidated by spectroscopic techniques. The detailed ^13C NMR assignments of baccatin Ⅳ are reported for the first time.  相似文献   

11.
A new mononuclear [Zn(H-1L)2] (L = 1H-indole-3-ethylene-salicylaldimine) was synthesized through the reaction of Zn(Ac)2, salicylaldehyde and tryptamine in hot ethanol solution and characterized by X-ray crystal structure analysis. The crystal belongs to monoclinic, space group P21/n with a = 15.014(2), b = 10.857(1), c = 17.489(1)A,β = 95.49(1)°, V = 2837.8(5) A^3, Z = 4, Dc = 1.386 g/cm^3, μ = 0.904 mm-1, F(000) = 1232, the final R = 0.0463 and wR = 0.0890 for 4990 independent reflections. In the complex, the Zn2+ ion presents a distorted N2O2 tetrahedral coordination involving two H-1L ligands.  相似文献   

12.
Synthesis and Structure Elucidation of Celangulin Derivatives   总被引:1,自引:0,他引:1  
Celangulins are sesquiterpene polyol esters based on a core structure known as β-dihydroagarofuran from Celastrus angulatus Max. Some of them are environment acceptable-pesticides. In order to find new active compounds and study their SAR, sesquiterpene polyol esters libraries were synthesized based on the basic hydrolysis of the extract of the root bark of Celastrus angulatus which could offer the β-dihydroagarofuran polyol by combinatorial chemical method and the compounds with insecticidal activity were isolated by bioassay-guided fractionation. Two new compounds with insecticidal activity against Mythimna separata, were isolated and elucidated as 2β,6α,8β, 13-tetraisobutanoyloxy-1β,4,9α-trihydroxy-β-dihydroagarofuran (A) and 1β,2β,6α,8β, 13-pentaisobutanoyloxy-4α,9α-dihydroxy-β-dihydroagarofuran (B) mainly by 1H NMR, 13C NMRH-HCOSY, HMQC, HMBC and HRMS spectral data. A: [α]20D -7.3 (c 0.12, CHCl3), B: [α]20D -34.6 (c 0.8,CHCl3).  相似文献   

13.
By hydrothermal synthesis, a manganese(H) tetracarboxylate [Mn(2,2′-bipyridi- ne)(btec)0.5(HEO)]En (H4btec = 1,2,4,5-benzenetetracarboxylic acid) was obtained and characterized by single-crystal X-ray diffraction, IR, elemental analysis and thermogravimetric analysis. It crystallizes in triclinic, space group P1, with a = 7.721(4), b = 8.905(5), c = 10.712(6)A, a = 80.899(8), β = 70.371(8), y = 78.201(8)°, Z = 2, V= 675.8(7)A3, Mr= 354.20, De= 1.741 g/cm^3,μ = 1.007 mm^-1, F(000) = 360, S = 0.956, (△/σ)max = 0.000, the final R = 0.0490 and wR = 0.1262. This compound presents an infinite 1D polymer featuring a double-chain structure. The Mn(Ⅱ) ion is five-coordinated. The four carboxylate groups of btec4- are all deprotonated and coordinated to four Mn atoms in a monodentate fashion, forming a 1D double chain structure with a cavity. Such chains are interconnected by π-π stacking interactions into 2D layers which are further interlinked into a supramolecular structure by hydrogen bonds.  相似文献   

14.
The single crystals of the azo copper(Ⅱ)-complex have been obtained from the solution of the compound dissolved in the ethanol by slow evaporation at room temperature. The structure was successfully determined by single-crystal X-ray diffraction. The crystal is of triclinic system, space group P1 with a = 7.8843(12), b = 11.5998(17), c = 13.955(2) , α = 112.214(2), β = 95.105(2), γ = 97.616(2)o, V = 1157.6(3) 3, Mr = 586.97, Z = 2, F(000) = 600, Dc = 1.684 g/cm3, μ(MoKα) = 1.120 mm-1, the final R = 0.0419 and wR = 0.1259 for 3475 observed reflections with I > 2σ(I). The coordination around copper(II) atom is a slightly distorted square-pyramidal geometry involving [Cu(C16H11N4O8S)(OH)H2O]-cation, one Na+ anion and one C2H5OH solvate molecule. The hydrogen bonds and π···π stacking interactions extend the complex into a three-dimensional framework.  相似文献   

15.
A new mononuclear Cu(Ⅱ) dithiocarbamate complex CuI(prdtc)(phen) 1 (prdtc = N-pyrrolidinyldithiocarbamate, phen = 1,10-phenanthroline) was synthesized and characterized by elemental analysis, IR spectrum, and single-crystal X-ray diffraction. The crystal belongs to the monoclinic system, space group P21/c with a = 8.7110(9), b = 14.7143(14), c = 14.8507(15) A, β = 109.721(6)°, V = 1791.9(3) A3, Z = 4, Dc = 1.916 g/cm3, CI7H16CulN3S2, Mr = 516.89, λ(MoKa) = 0.71073A,μ = 3.178 mm^-1, F(000) = 1012, the final R = 0.0369 and wR = 0.0987. A total of 4082 unique reflections were collected, of which 2916 with I 〉 2σ(I) were observed. The Cu(Ⅱ) atom is five-coordinated in a distorted square-pyramidal geometry by one I atom in the apical position, two S atoms from a prdtc ligand and two N atoms from a phen ligand in the basal plane. There exist face-to-face aromatic π-π stacking interactions between adjacent phen ligands stabilizing the structure and making the complex assemble into a 1D structure along the a axis. It can be concluded that the difference of the dtc flexibility and reaction conditions result in the structural difference between complex 1 and CuI(dmdtc)(phen) (dmdtc = N, N-dimethyldithiocarbamate).  相似文献   

16.
WANG  Chuan-Jin ZHU  Guang-Jun 《结构化学》2012,31(8):1140-1144
The title compound,3β-acetoxy-20(29)-lupen-28-aldehyde,is a pentacyclic triterpene which was first isolated from the acetyl acetate fraction of Platanus acerifolia Willd bark and characterized by 1 H-NMR and 13 C-NMR.Besides,the crystal of the compound was acquired,and the relative configuration of 3β-acetoxy-20(29)-lupen-28-aldehyde was determined by single-crystal X-ray diffraction analysis for the first time.It crystallizes in the monoclinic system,space group C2 with a=14.428(3),b=6.6620(13),c=30.399(6),β=103.73(3)°,Z=4,C32 H50 O3,M r=482.72,Dc =1.130 g/cm 3,V=2838.5(10)3,μ(MoKa)=0.070 mm-1,F(000)= 1064,the final R=0.0657 and wR=0.1855 for 2839 independent reflections (R int=0.0802)and 1963 observed ones (I>2(I)).Intramolecular van der waals force contributes to the stability of the structure.  相似文献   

17.
18.
In our continuing research works on Panax notoginseng (Burk.) F. H. Chen, a famous traditional Chinese herb medicine1, two new dammarane glycosides named notoginsenosides T1 (1) and T2 (2) were isolated from the mild acid hydrolysis products of the root saponins. We report herein the structure elucidation of these two novel glycosides.Notoginsenosides T1(1) was obtained as white solid, [(] = +14.49 (0.50, MeOH). Its negative mode HR-FAB-MS spectrum showing the quasimolecular ion peak a…  相似文献   

19.
Two new C-21 steroidal glycosides, mucronatosides M(1) and N(2), were isolated from the stems of Stephanotis mucronata, together with one known compound stephanoside M(3). On the basis of chemical evidence and extensive spectroscopic methods, including one-dimensional and two-dimensional NMR, the structures of the two new compounds were identified as 12-O-tigloyl-20-O-N-methylanthraniloyl sarcoslin 3-O-β-D-glucopyranosyl-(1→4)-6- deoxy-3-O-methyl-β-D-allopyranosyl-(→4)-β-D-cymaropyranosyl-(1→4)-β-D-cymaropyranoside (1), and 12-O- cinnamoyl-20-O-nicotinoyl( 2OS)-pregn-6-ene-3 β,5α,8βm12 β,14β,17β,20-heptanol 3-O-β-D-glucopyranosyl-(1→4)-6- deoxy-3-O-methyl-β-D-allopyranosyl-(1→4)-β-D-cymaropyranosyl-(1→4)-β-D-cymaropyranoside (2).  相似文献   

20.
The crystal of(24R)-3β,5α-dihydroxy-24-ethyl-5α-cholestan-6-one(1)was isolated from the leaves of P.nagi planted in Fujian for the first time with the same skel...  相似文献   

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