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1.
Abstract

A new series of water soluble platinum(II) complexes of the type [Pt(DACH)[R-CH(COO)2]], wherein DACH represents IR,2R-cyclohexanediamine and R represents formamido. acetamido, (penta-O-acctyl-gluconyl)amino, and gluconylamino have been synthesized. The modes of binding of amidodicarboxylic acid derivatives in these complexes have been determined by various spectroscopic techniques: 1H, 13 C, and 195PtNMR; 2D-COSY{1H-1H} and 2D-HETCOSY{1H-13C} NMR, MS(FAB), IR and conductivity measurements.  相似文献   

2.
A new trihydroxy sesquiterpene, rel‐(1R,4aR,5S,6S,7S,8aR)‐decahydro‐6,8a‐dimethyl‐5‐(propan‐2‐yl)naphthalene‐1,6,7‐triol ( 1 ), has been isolated as a result of the phytochemical investigation on the CH2Cl2 extract of Teucrium mascatense. The structure elucidation of the new constituent was carried out by the combined use of 1D‐ (1H‐ and 13C‐NMR) and 2D‐NMR (HMBC and HSQC) spectroscopic analysis, along with mass spectrometric techniques. In addition to the new constituent 1 , the known metabolite 2 , previously isolated from Crataegus pinnatifida, was also identified.  相似文献   

3.
The connectivities of all atoms in ascorbigen A, an important metabolite, were determined unambiguously for the first time. The connectivity between carbon atoms was established by 2D INADEQUATE, and one-bond 13C–13C coupling constants were determined for all pairs of directly connected carbon atoms except for two strongly coupled carbon pairs. The 13C–13C coupling in one of the pairs was proved by a modification of standard INADEQUATE; however, the signals from the other pair were too weak to be observed. The connectivity within the two strongly coupled C–C pairs was confirmed by a combination of COSY and gHSQC; the latter experiment also identified all C–H bonds. The proton nuclear magnetic resonance (1H NMR) spectra in dry dimethyl sulfoxide allowed identification and assignment of the signals due to NH and OH protons. The derived structure, 3-((1H-indol-3-yl)methyl)-3,3a,6-trihydroxytetrahydrofuro[3,2-b]furan-2(5H)-one, agrees with the structure suggested for ascorbigen A in 1966. The density functional theory (DFT) calculations showed that among 16 possible stereoisomers, only two complied with the almost zero value of the measured 3J(H6–H6a). Of the two stereoisomers, 3S,3aS,6S,6aR and 3R,3aR,6R,6aS, the latter was excluded on synthetic grounds. The nuclear Overhauser effect measurements unveiled close proximity between H2′ proton of the indole and the H6a proton of the tetrahydrofuro[3,2-b]furan part. Detailed structural interpretation of the measured NMR parameters by means of DFT NMR was hampered by rotational flexibility of the indole and tetrahydrofuro[3,2-b]furan parts and inadequacy of Polarizable Continuum Model (PCM) solvent model.  相似文献   

4.
Two new compounds cadin-2-en-1β-ol-1β-D-glucuronopyranoside (1), guaia-l,7-dien-3β,13-diol-13α-D- glucofuranoside (2) along with three known compounds have been isolated from the culture hairy roots of Catharanthus roseus. Their structures have been elucidated with the help of 500 MHz NMR using 1D and 2D spectral methods: viz: ^1H and ^13C NMR, ^1H-^1H COSY, ^1H-^13C HETCOR and DEPT aided by ELMS, FAB-MS, HR-FABMS and IR spectroscopy.  相似文献   

5.
Oxidation of (+)-sabinol, (1S,3R,5S)-1-isopropyl-4-methylidenebicyclo[3.1.0]hexan-3-ol, by active MnO2 afforded not the expected sabinone but only its [4+2]-cyclodimer. The molecular structure of the latter was established by X-ray diffraction analysis. The 1H and 13C NMR spectra of this cyclodimer were interpreted using 2D NMR spectroscopy.  相似文献   

6.
A new germacranolide, ajanolide A, was isolated from aerial parts ofAjania fruticulosa by means of extraction with CHCl3 and adsorption chromatography. This compound was identified as (1(10)E,3S,4Z,6R,7S,11R)-3-acetoxygermacra-1(10),4-dien-12,6-olide ((1S,7S,10R,13R)-7-acetoxy-4,8,13-trimethyl-11-oxabicyclo[8.3.0]trideca-4(E),8(Z)-dien-12-one) by X-ray diffraction analysis. 2D1H−1H (COSY) and13C−1H (COSY) NMR spectroscopy was used for assigning the1H and13C NMR signals in the spectra of ajanolide A. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 1, pp. 167–170, January, 1998.  相似文献   

7.
Two new highly oxidized humulane sesquiterpenes, mitissimols F ( 1 ) and G ( 2 ), were isolated from the fruiting bodies of Lactarius mitissimus. Their structures were elucidated by using extensive spectroscopic techniques including 1D‐ and 2D‐NMR experiments. The absolute configuration of mitissimol F ( 1 ) was determined by 1H‐NMR resolution of its diastereoisomeric α‐methoxy‐α‐(trifluoromethyl)benzeneacetates (MTPA). It was shown to be (1S,3E,6S,8R,9R,10S,11R)‐8,9 : 10,11‐diepoxy‐1,6‐dihydroxyhumul‐3‐en‐5‐one (=(1S,2R,4R,6S,8E,11S,12R)‐6,11‐dihydroxy‐1,6,10,10‐tetramethyl‐3,13‐dioxatricyclo[10.1.0.02,4]tridec‐8‐en‐7‐one).  相似文献   

8.
Two new ceramides were isolated from the bulbs of Zephyranthes candida. Their structures were established as (2S,3S,4R,13E)-1,3,4-trihydroxy-2-[(2′R)-2′-hydroxytetracosanoylamino]-13-octadecene, named zephyranamide A (1) and (2S,3S,4R)-1,3,4-trihydroxy-2-octacosanoylaminohexadecene, named zephyranamide B (2). The structures of the new compounds were elucidated by spectral techniques including 1H NMR, 13C NMR, as well as HSQC, HMBC, DEPT, and COSY.  相似文献   

9.
The novel briarane diterpenoids verecynarmin B(=(?)-(1R*, 10S*, 11R*, 4E, 12Z)-briara-4,7,12,17,-tetraen-14-one; (?)- 4 ); verecynarmin C (=(?)-(1R*, 10R*, 11S*, 4E, 12Z)?11-hydroxybriara-4,7,12,17-tetraen-14-one; (?)- 5 ); and verecynarmin D (=(?)-(1R*, 10R*, 11R*, 4E, 12E)-13-chloro-11-hydroxybriara-4,7,12,17,-tetraen-14-one; (?)- 6 ) are reported here as constituents of both the Mediterranean nudibranch mollusc Armina maculata (Rafinesque) and its prey, the pennatulacean octocoral Veretillum cynomorium (PALLAS ). The structural assignments rest mainly on (i) establishing that these briaranes occur in solution as two stable conformers which interconvert slowly (ca. 10 time per second at r.t. according to dynamic NMR) by 180° flipping of the C(4)?C(5) group in the ten-membered ring (Scheme 1), (ii) deriving, for both conformers, 1H, 1H coupling constants from 1D spectra, as well as 1H, 1H, 13C, 1H, and 13C, 1H, and 13C, 13C, correlations from 2D experiments; (iii) subjecting the briaranes to SeO2 oxidation at the C(16) methyl group with isomerization at the C(4)=C(5) bond to give, in each case, only one observable molecular species as shown by NMR spectroscopy (Scheme 2).  相似文献   

10.
2-Hydroxy-13-oxo-tricyclo[7.3.1.02,7]tridecane derivatives can be obtained by reaction of cyclohexanone with alcohols under alkaline conditions. The unambiguous assignment of all signals of the1H-NMR- and13C-NMR-spectrum is possible by 2D-1H-13C-shift correlation and 2D-INADEQUATE. Compound1 crystallizes in space group P21/n witha=8.518 (1),b=14.789 (2),c=19.321 (2) Å, =94.91 (1)°,Z=8,D c =1.22 Mg cm–3. The structure refined toR=0.100 andR w =0.097 for 1719 observed reflections. Two independent molecules form centrosymmetric hydrogen-bonded dimers.Part V:Haslinger E.,Kalchhau-ser H.,Robien W.,Steindl H., Monatsh. Chem.115, 597 (1984).  相似文献   

11.
In this study, we reported the synthesis of three kinds of mono-functional pillar[5]arene derivatives PRI, PRII and R and their structures were studied by 1D and 2D NMR spectra and mass spectra. The 2D NMR spectra including 1H-13C HSQC, 1H-1H COSY and NOESY spectra indicated that PRI and PRII are both stable self-included pseudo[1]rotaxanes in CDCl3. These original structures are promising compounds for the design of pillar[5]-based [1]rotaxane. And the results showed that R could exist stable in CDCl3 and DMSO because of the coordination of N-H?O hydrogen bonding interaction and C-H?π interaction.  相似文献   

12.
The authors developed four variants of the qNMR technique (1H or 13C nucleus, DMSO-d6 or CDCl3 solvent) for identification and quantification by NMR of 22R and 22S epimers in budesonide active pharmaceutical ingredient and budesonide drugs (sprays, capsules, tablets). The choice of the qNMR technique version depends on the drug excipients. The correlation of 1H and 13C spectra signals to molecules of different budesonide epimers was carried out on the basis of a comprehensive analysis of experimental spectral NMR data (1H-1H gCOSY, 1H-13C gHSQC, 1H-13C gHMBC, 1H-1H ROESY). This technique makes it possible to identify budesonide epimers and determine their weight ratio directly, without constructing a calibration curve and using any standards. The results of measuring the 22S epimer content by qNMR are comparable with the results of measurements using the reference HPLC method.  相似文献   

13.
1-Phenyl-cyclopenteno[1,2-d]-1,2,3-rriazolo-5-spiro-4′-[perhydropyrazolino-3′,5′-dione] (5) afforded in situ, by oxidation with lead tetraacetate, the corresponding cyclopentenotriazolo-spiropyrazolodione 6 , which was trapped with dienes giving the hetero-Diels-Alder adducts 10–12 in good yields. The Diels-Alder reactions were examined on the basis of AM1 MO calculations. Total assignment of the 1H- and 13C-nmr chemical shifts as well as the relative configuration of these adducts was accomplished with the help of 2D (1H-1H COSY, 1H -1 H NOESY, 1H-13C XHCORR, 1H-13C COLOC) and NOE difference spectroscopy. The structures of compounds 11a and 11b were also examined by molecular modeling.  相似文献   

14.
A new benzofuran, methyl (2S,2″S,3′E)-[2-(1″-acetoxypropan-2-yl)-2,3-dihydrobenzofuran-5-yl]acrylate (1), and 13 known compounds (214) were isolated from an ethanol extract of Artemisia halodendron Turcz. ex Bess. The chemical structures of these compounds were determined by 1D and 2D NMR (1H-1H COSY, HMBC, HMQC and NOESY) and HR-ESI-MS spectra, and results were compared with data from the literature. The effects of compounds 114 were measured on NF-κB activation, with compounds 2 and 3 exhibiting inhibitory activities against TNF-α-induced NF-κB reporter gene expression in HeLa cells from 10 to 100 μM.  相似文献   

15.
Three new lanostane‐type triterpenoids, inonotsutriols A ( 1 ), B ( 2 ), and C ( 3 ) were isolated from the sclerotia of Inonotus obliquus (Pers .: Fr.) (Japanese name: kabanoanatake; Russian name: chaga). Their structures were determined to be (3β,21R,24S)‐21,24‐cyclolanost‐8‐ene‐3,21,25‐triol ( 1 ), (3β,21R,24R)‐21,24‐cyclolanost‐8‐ene‐3,21,25‐triol ( 2 ), and (3β,21R,24S)‐21,24‐cyclolanosta‐7,9(11)‐diene‐3,21,25‐triol ( 3 ) on the basis of NMR spectroscopy including 1D and 2D experiments (1H,1H‐COSY, NOESY, HMQC, and HMBC) and EI‐MS.  相似文献   

16.
报道了以双溴代烷烃和刺乌头碱合成刺乌头碱氢溴酸盐的方法. 用元素分析、红外光谱、高分辨质谱和核磁共振进行了表征. 并用X射线单晶衍射确定了标题化合物的绝对构型. 晶体结构表明, 该化合物通过分子间氢键形成了网状类似超分子结构. 晶体属于单斜晶系, P21空间群, 晶胞参数: a=1.0619(2) nm, b=1.2196(3) nm, c=1.2282(2) nm, β=90.87(1)°, V=1.59037(54) nm3, Z=2, Dm=1.428 g/cm-3, F(000)=720.0, µ=1.349 mm-1. 环 A, B, C, D, E和F分别呈船式、椅式、信封式、船式、船式和信封式. 其绝对构型被确定为1S,4S,5S,7S,8S,9S,10S,11S,13R,14S,16S,17R.  相似文献   

17.
From cultures of a Phoma species (strain S 298) the hitherto unknown metabolite deoxaphomine has been isolated. On the basis of the spectral data, structure 1 of the (7S, 16R, 20R)-7,20-dihydroxy-16-methyl-10-phenyl-[13]cytochalasa-6(12),13t,21t-triene-1,23-dione is assigned to deoxaphomine. This structure is confirmed by the chemical degradation of 1 , yielding the products 4 and 6 which are identical with derivatives of phomine ( 2 )((7S,16R,20R)-7,20-dihydroxy-16-methyl-10-phenyl-24-oxa-[14]cytochalasa-6(12), 13t,21t-triene-1,23-dione) and cytohalasin D ( 8 ) ((7S,16S,18R,21R)-21-acetoxy-7,18-dihydroxy-16,18-dimethyl-10-phenyl-[11]sytochalasa-6(12),13t,19t-triene-1,17-dione). Deoxaphomine ( 1 ) is a potential biogenetic precursor of the 24-oxa-[14]cytochalasans. Preliminary results of the biological activity of deoxaphomine are reported.  相似文献   

18.
(1R,2R,3S,4R,7R)‐7‐Isopropyl‐6‐methylbicyclo[2.2.2]oct‐5‐ene‐2,3‐dicarboxylic acid anhydride (tetrahydro‐4,7‐ethanoisobenzofuran‐1,3‐dione derivative) adduct 2 was prepared via the isomerization of α‐pinene and β‐pinene in turpentine followed by the Diels‐Alder cycloaddition with maleic anhydride in the presence of phosphoric acid/iodine catalysis. The molecular structure of adduct 2 was characterized by IR, 1H NMR, 13C NMR, 1H‐1H COSY, DEPT, HSQC, HMBC, 2D NOESY and MS spectra. The single crystal X‐ray crystallographic analysis of adduct 2 was performed, and the X‐ray powder diffractive spectrum of the sample adduct 2 is consistent with the diffractive spectrum calculated from the single crystal data. Therefore the structure and stereochemistry of adduct 2 was established based on extensive spectral data and single crystal X‐ray analysis.  相似文献   

19.
The 13C and 1H NMR spectra of (–)-bis[1R, 3 R, 4S]menthylphosphine (1) are assigned by two-dimensional double quantum NMR and 13C? 1H shift correlation diagrams. The variable temperature spectra of 1 indicate hindered rotation about the P? C bonds.  相似文献   

20.
To study the conversion from a meso form to a racemic form of tetrahydrofurantetracarboxylic acid (H4L), seven novel coordination polymers were synthesized by the hydrothermal reaction of Zn(NO3)2 ? 6 H2O with (2S,3S,4R,5R)‐H4L in the presence of 1,10‐phenanthroline (phen), 2,2′‐bipyridine (2,2′‐bpy), or 4,4′‐bipyridine (4,4′‐bpy): [Zn2{(2S,3S,4R,5R)‐L}(phen)2(H2O)] ? 2 H2O ( 1 ), [Zn4{(2S,3R,4R,5R)‐L}{(2S,3S,4S,5R)‐L}(phen)2(H2O)2] ( 2 ), [Zn2{(2S,3S,4R,5R)‐L}(H2O)2] ? H2O ( 3 ), [Zn4{(2S,3R,4R,5R)‐L}{(2S,3S,4S,5R)‐L} (2,2′‐bpy)2(H2O)2] ? 2 H2O ( 4 ), [Zn2 {(2S,3S,4R,5R)‐L}(2,2′‐bpy)(H2O)] ( 5 ), [Zn4{(2S,3R,4R,5R)‐L}{(2S,3S,4S,5R)‐L} (4,4′‐bpy)2(H2O)2] ( 6 ), and [Zn2 {(2S,3S,4R,5R)‐L}(4,4′‐bpy)(H2O)] ? 2 H2O ( 7 ). These complexes were obtained by control of the pH values of reaction mixtures, with an initial of pH 2.0 for 1 , 2.5 for 2 , 4 , and 6 , and 4.5 for 3 , 5 , and 7 , respectively. The expected configuration conversion has been successfully realized during the formation of 2 , 4 , and 6 , and the enantiomers of L, (2S,3R,4R,5R)‐L and (2S,3S,4S,5R)‐L, are trapped in them, whereas L ligands in the other four complexes retain the original meso form, which indicates that such a conversion is possibly pH controlled. Acid‐catalyzed enol–keto tautomerism has been introduced to explain the mechanism of this conversion. Complex 1 features a simple 1D metal–L chain that is extended into a 3D supramolecular structure by π–π packing interactions between phen ligands and hydrogen bonds. Complex 2 has 2D racemic layers that consist of centrosymmetric bimetallic units, and a final 3D supramolecular framework is formed by the interlinking of these layers through π–π packing interactions of phen. Complex 3 is a 3D metal–organic framework (MOF) involving meso‐L ligands, which can be regarded as (4,6)‐connected nets with vertex symbol (45.6)(47.68). Complexes 4 and 5 contain 2D racemic layers and (6,3)‐honeycomb layers, respectively, both of which are combined into 3D supramolecular structures through π–π packing interactions of 2,2′‐bpy. The structure of complex 6 is a 2D network formed by 4,4′‐bpy bridging 1D tubes, which consist of metal atoms and enantiomers of L. These layers are connected through hydrogen bonds to give the final 3D porous supramolecular framework of 6 . Complex 7 is a 3D MOF with novel (3,4,5)‐connected (63)(42.64)(42.66.82) topology. The thermal stability of these compounds was also investigated.  相似文献   

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