首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 31 毫秒
1.
From the seeds of Evonymus europaea L. (Celastraceae) the three previously described alkaloids A, B and C were isolated and their empirical formulae determined by mass spectrometry. Alkaloid B, now named evozine, C32H39NO15 ( 14 ), alkaloid A, now named evorine, C34H41NO16 ( 15 ), and alkaloid C, shown to be identical with Parter's & Libiseller's evonine, C36H43NO17 ( 17 ), are respectively tri-, tetra-, and penta-O-acetyl derivatives of deacetylevonine ( 13 ), C26H33NO12. Vigorous alkaline hydrolysis of the latter yields the previously known evonic acid ( 3 ). Deacetylevonine ( 13 ) is an ester of evonic acid ( 3 ) and a hypothetical polyhydroxy compound C15H24O10 ( 2 ), which is unstable on alkaline hydrolysis. By partial saponification and partial acetylation, these three alkaloids can be converted into each other, at the same time giving rise to a fourth alkaloid D ( 16 ), C34H41NO16, which we name iso-evorine. This had been obtained already by M. Osowiecki (unpublished).  相似文献   

2.
Four distinct hydrogen‐bonding topologies were observed in the structures of six diethanolamine ligands. These compounds are (1R*,2R*)‐2‐[(2‐hydroxyethyl)(methyl)amino]‐1,2‐diphenylethanol, C17H21NO2, (I), 1‐[(2S)‐2‐(hydroxydiphenylmethyl)pyrrolidin‐1‐yl]‐2‐methylpropan‐2‐ol, C21H27NO2, (II), 2‐[(2‐hydroxyethyl)(methyl)amino]‐1,1‐diphenylethanol, C17H21NO2, (III), 1‐{(2‐hydroxy‐2‐methylpropyl)[(1S)‐1‐phenylethyl]amino}‐2‐methylpropan‐2‐ol, C16H27NO2, (IV), 1‐{[(2R)‐2‐hydroxy‐2‐phenylethyl][(1S)‐1‐phenylethyl]amino}‐2‐methylpropan‐2‐ol, C20H27NO2, (V), and (1R*,2S*)‐2‐[(2‐hydroxyethyl)(methyl)amino]‐1,2‐diphenylethanol, C17H21NO2, (VI). In each compound, all `active' hydroxy H atoms are engaged in hydrogen bonding, but the N atoms are not involved in intermolecular hydrogen bonding. In the structures of (I), (II) and (IV)–(VI), molecules are linked into chains by intermolecular O—H...O interactions. These chains are organized in such a way as to hide the hydrophilic groups inside, and so the outer surfaces of the chains are hydrophobic. The structure of (VI) contains two distinct non‐equivalent systems of intermolecular O—H...O hydrogen bonds formed by disordered hydroxy H atoms.  相似文献   

3.
(2R*,4S*)‐Methyl 2,3,4,5‐tetrahydro‐1,4‐epoxy‐1H‐benz[b]azepine‐2‐carboxylate, C12H13NO3, (I), and its reduction product (2R*,4S*)‐methyl 4‐hydroxy‐2,3,4,5‐tetrahydro‐1H‐benz[b]azepine‐2‐carboxylate, C12H15NO3, (II), both crystallize as single enantiomers in the space group P212121, while the hydrolysis product (2RS,4SR)‐4‐hydroxy‐2,3,4,5‐tetrahydro‐1H‐benz[b]azepine‐2‐carboxylic acid, C11H13NO3, (III), and the lactone (2RS,5SR)‐8‐(trifluoromethoxy)‐5,6‐dihydro‐1H‐2,5‐methanobenz[e][1,4]oxazocin‐3(2H)‐one, C12H10F3NO3, (IV), both crystallize as racemic mixtures in the space group P21/c. The molecules of compound (IV) are linked into centrosymmetric R22(10) dimers by N—H...O hydrogen bonds, and those of compound (I) are linked into chains by C—H...π(arene) hydrogen bonds. A combination of O—H...O and O—H...N hydrogen bonds links the molecules of compound (III) into sheets containing equal numbers of R44(14) and R44(26) rings, and a combination of C—H...π(arene) hydrogen bonds and three‐centre O—H...(N,O) hydrogen bonds links the molecules of compound (II) into a three‐dimensional framework structure. Comparisons are made with some related compounds.  相似文献   

4.
The title compounds, both [Fe(C5H5)(C15H14NO2)], crystallize with Z′ = 2 in the centrosymmetric space group P. In each compound, there is an intra­molecular N—H⋯O=C hydrogen bond, and pairs of inter­molecular O—H⋯O=C hydrogen bonds link the mol­ecules into chains, parallel to [10] in the 3‐hydr­oxy compound and parallel to [10] in the 4‐hydr­oxy compound.  相似文献   

5.
7-(CH3)3N-4-{2,4-(NO2)2C6H3S}-nido-7-CB10H11 has been synthesized through a Friedel-Crafts substitution reaction on 7-(CH3)3N-nido-7- CB10H12. A biodistribution study in mice with implanted B16 melanoma indicates that the compound locates in neoplastic tissue at concentrations which suggest that its use in 10B neutron capture therapy may be feasible.  相似文献   

6.
In the title compound, [Zn(C7H6NO2)(NO3)(H2O)]n, the Zn atom is coordinated by two nitrate ions, one aqua molecule and two 4‐aminobenzoate ions in a distorted octahedral geometry. The structure of the compound exhibits a two‐dimensional layer, which is formed by the interconnection of [Zn(C7H6NO2)(H2O)]n chains viaμ2‐nitrate bridges or by the interconnection of [Zn(NO3)(H2O)]n chains viaμ2‐4‐aminobenzoate bridges.  相似文献   

7.
A multicomponent pharmaceutical salt formed by the isoquinoline alkaloid berberine (5,6‐dihydro‐9,10‐dimethoxybenzo[g]‐1,3‐benzodioxolo[5,6‐a]quinolizinium, BBR) and the nonsteroidal anti‐inflammatory drug diclofenac {2‐[2‐(2,6‐dichloroanilino)phenyl]acetic acid, DIC} was discovered. Five solvates of the pharmaceutical salt form were obtained by solid‐form screening. These five multicomponent solvates are the dihydrate (BBR–DIC·2H2O or C20H18NO4+·C14H10Cl2NO2?·2H2O), the dichloromethane hemisolvate dihydrate (BBR–DIC·0.5CH2Cl2·2H2O or C20H18NO4+·C14H10Cl2NO2?·0.5CH2Cl2·2H2O), the ethanol monosolvate (BBR–DIC·C2H5OH or C20H18NO4+·C14H10Cl2NO2?·C2H5OH), the methanol monosolvate (BBR–DIC·CH3OH or C20H18NO4+·C14H10Cl2NO2?·CH3OH) and the methanol disolvate (BBR–DIC·2CH3OH or C20H18NO4+·C14H10Cl2NO2?·2CH3OH), and their crystal structures were determined. All five solvates of BBR–DIC (1:1 molar ratio) were crystallized from different organic solvents. Solvent molecules in a pharmaceutical salt are essential components for the formation of crystalline structures and stabilization of the crystal lattices. These solvates have strong intermolecular O…H hydrogen bonds between the DIC anions and solvent molecules. The intermolecular hydrogen‐bond interactions were visualized by two‐dimensional fingerprint plots. All the multicomponent solvates contained intramolecular N—H…O hydrogen bonds. Various π–π interactions dominate the packing structures of the solvates.  相似文献   

8.
In the title compounds, 4‐aminopyridinium 4‐aminobenzoate dihydrate, C7H6NO2·C5H7N2+·2H2O, (I), and 4‐aminopyridinium nicotinate, C5H7N2+·C6H4NO2, (II), the aromatic N atoms of the 4‐aminopyridinium cations are protonated. In (I), the asymmetric unit is composed of two 4‐aminopyridinium cations, two 4‐aminobenzoate anions and four water molecules, and the compound crystallizes in a noncentrosymmetric space group. The two sets of independent molecules of (I) are related by a centre of symmetry which is not part of the space group. In (I), the protonated pyridinium ring H atoms are involved in bifurcated hydrogen bonding with carboxylate O atoms to form an R12(4) ring motif. The water molecules link the ions to form a two‐dimensional network along the (10) plane. In (II), an intramolecular bifurcated hydrogen bond generates an R12(4) ring motif and inter‐ion hydrogen bonding generates an R42(16) ring motif. The packing of adduct (II) is consolidated via N—H...O and N—H...N hydrogen bonds to form a two‐dimensional network along the (10) plane.  相似文献   

9.
在溶剂热条件下,利用L-异亮氨酸衍生物配体(C13H19NO3)与Zn(NO3)2·6H2O合成了配位聚合物[Zn2(C13H17NO3)2]n(1)。单晶X射线衍射结果显示化合物1结晶于单斜晶系P21空间群,配体与金属离子桥联形成二维层状结构,层与层间通过范德瓦耳斯力形成了三维超分子网络结构。在化合物1合成过程中加入罗丹明B(Rho-B),可以得到复合材料2。荧光测试结果显示,在激发波长为370nm时,化合物1主要是基于配体的发光,而复合物2除配体的发光外,在580nm处出现了Rho-B的发射峰。利用配体与Rho-B发射峰相对强度的比值为检测信号,将复合物2应用于金属阳离子和挥发性有机物(VOCs)检测。实验结果显示该材料能在水溶液中选择性识别Cr3+离子,并且在短时间内对苯甲醛蒸气作出响应。  相似文献   

10.
The octahedral title compound, [Ru(C2H5O)(NO)(NO2)2(C6H16N2)], crystallizes in the rhombohedral space group P31 with an ethoxy ligand axially coordinated trans to the nitro­syl ligand. The RuII ion is equatorially coordinated by a tetramethylethylenediamine group acting as a bidentate ligand, and to two nitro moieties whose planes are tilted with respect to the mean equatorial plane. Each nitro­gen ligand bonded to the metallic centre has a different hybridization state.  相似文献   

11.
A series of five binary complexes, i.e. three cocrystals and two molecular salts, using 2‐chloro‐4‐nitrobenzoic acid as a coformer have been produced with five commonly available compounds, some of pharmaceutical relevance, namely, 2‐chloro‐4‐nitrobenzoic acid–isonicotinamide (1/1), C7H4ClNO4·C6H6N2O, 2‐chloro‐4‐nitrobenzoic acid–3,3‐diethylpyridine‐2,4(1H,3H)‐dione (2/1), 2C7H4ClNO4·C9H13NO2, 2‐chloro‐4‐nitrobenzoic acid–pyrrolidin‐2‐one (1/1), C7H4ClNO4·C4H7NO, 2‐carboxypiperidinium 2‐chloro‐4‐nitrobenzoate, C6H12NO2?·C7H3ClNO4?, and (2‐hydroxyethyl)ammonium 2‐chloro‐4‐nitrobenzoate, C2H8NO+·C7H3ClNO4?. The coformer falls under the classification of a `generally regarded as safe' compound. All five complexes make use of a number of different heteromeric hydrogen‐bonded interactions. Intermolecular potentials were evaluated using the CSD‐Materials module.  相似文献   

12.

The compound, [Ni(phen)3]NO3 · C2H5OP(O)O · 3H2O, was obtained by the reaction of Ni(NO3)2, C2H5OP(OH)2 and 1,10-phenanthroline in 95% EtOH solution, and was characterized using IR and UV spectra and magnetic susceptibility measurements over the temperature range 75-300 K. The red crystal is triclinic of space group P&1macr;, with lattice parameters a = 12.462(3), b = 13.416(3), c = 13.422(3) Å, f = 75.88(3), g = 64.75(3), n = 65.87(3)°, and Z = 2. The coordinated cation contains a six-coordinate nickel atom chelated by three phenanthroline ligands, resulting in a distorted octahedral arrangement with the six Ni-N distances ranging from 2.086(2) to 2.113(3) Å. In addition to the nickel coordination complex, there are two anions, NO3 and C2H5OP(O)O-, and three water molecules which complete the crystal structure. In the solid state, the title compound forms a three dimensional network structure through hydrogen bonds. The intermolecular hydrogen bonds connect the [Ni(phen)3]2+, NO3, C2H5OP(O)O- and H2O molecules.  相似文献   

13.
Reactions of isopropoxides of praseodymium, neodymium and samarium with bifunctional tridentate and tetradentate schiff bases (i.e. salicylidene-O-aminophenol and bis-salicylaldehyde ethylenediamine) have been carried out in benzene in different stoichiometric ratios resulting in the formation of products with the formula M(OPri)(C11H9NO2), M(C13H9NO2)(C13H10NO2). M2(C13H9NO2) M(OPri)(C15H14N2O2), M(C16H14N2O2)(C16H15N2O2) and M2(C16H14N2O2)3 (where M stands for Pr, Nd and Sm). The products were found to be yellow to orange solids soluble in benzene and alcohol. The absorption spectra of these complexes were also recorded in methanol.  相似文献   

14.
The structures of di­aqua(1,7‐dioxa‐4‐thia‐10‐aza­cyclo­do­decane)­nickel dinitrate, [Ni(C8H17NO2S)(H2O)2](NO3)2, (I), bis­(nitrato‐O,O′)(1,4,7‐trioxa‐10‐aza­cyclo­do­decane)­mercury, [Hg(NO3)2(C8H17NO3)], (II), and aqua­(nitrato‐O)(1‐oxa‐4,7,10‐tri­aza­cyclo­do­decane)copper nitrate, [Cu(NO3)(C8H19N3O)(H2O)]NO3, (III), reveal each macrocycle binding in a tetradentate manner. The conformations of the ligands in (I) and (III) are the same and distinct from that identified for (II). These differences are in agreement with molecular‐mechanics predictions of ligand conformation as a function of metal‐ion size.  相似文献   

15.
The isostructural salts benzene‐1,2‐diaminium bis(pyridine‐2‐carboxylate), 0.5C6H10N22+·C6H4NO2?, (1), and 4,5‐dimethylbenzene‐1,2‐diaminium bis(pyridine‐2‐carboxylate), 0.5C8H14N22+·C6H4NO2?, (2), and the 1:2 benzene‐1,2‐diamine–benzoic acid cocrystal, 0.5C6H8N2·C7H6O2, (3), are reported. All of the compounds exhibit extensive N—H…O hydrogen bonding that results in interconnected rings. O—H…N hydrogen bonding is observed in (3). Additional π–π and C—H…π interactions are found in each compound. Hirshfeld and fingerprint plot analyses reveal the primary intermolecular interactions and density functional theory was used to calculate their strengths. Salt formation by (1) and (2), and cocrystallization by (3) are rationalized by examining pKa differences. The R22(9) hydrogen‐bonding motif is common to each of these structures.  相似文献   

16.
A new platinum(II) complex with methionine sulfoxide was synthesized and characterized by chemical and spectroscopic techniques. Elemental analyses, mass spectrometric measurements (electrospray ionization quadrupole time-of-flight mass spectrometry), and thermal analyses of the solid compound fit the composition [(C5H10NO3S)Pt(µ-Cl)2Pt(C5H10NO3S)]?·?2.5H2O. Infrared spectroscopic data indicate coordination of the ligand to Pt(II) through the nitrogen of NH2 and the sulfur of the S=O group. 1H-15N nuclear magnetic resonance spectroscopic data confirm nitrogen coordination. Antibacterial activities were evaluated by antibiogram assays using the disc diffusion method. The platinum(II) complex showed antibacterial activity against Gram-negative Pseudomonas aeruginosa bacterial cells.  相似文献   

17.
Summary The reaction of peroxyacetyl radicals with reduced sulfur compounds was studied at 55°C in N2 at 1 000 mbar total pressure. The radicals were generated in equilibrium with peroxyacetyl nitrate and NO2 in large excess. The pseudo first order decay ofPAN was measured in the absence and presence of several 100 ppm CH3SH, C2H5SH,n-C4H9SH, (CH3)2S, and (CH3S)2. Computer simulations yielded the following rate constants of peroxyacetyl radicals with the above mentioned sulfur compounds: 3.7, 2.8, 13.0, 0.9, and 1.8·10–16 cm3/s, respectively. An electron capturing compound of the thiols with NO2 was observed.
Reaktionen von Peroxyacetylradikalen mit reduzierten Schwefelverbindungen
Zusammenfassung Die Reaktionen von Peroxyacetylradikalen mit reduzierten Schwefelverbindungen wurden bei 55°C in NO2 bei einem Totaldruck von 1 000 mbar untersucht. Die Radikale wurden im Gleichgewicht mit Peroxyacetylnitrat und NO2 in großem Überschuß generiert. Der nach erster Ordnung verlaufende Zerfall vonPAN wurde in Abwesenheit und Anwesenheit und von einigen ppm CH3SH, C2H5SH,n-C4H9SH, (CH3)2S und (CH3S)2 gemessen. Computersimulierung der Geschwindigkeitskonstanten für die Peroxyacetylradikale ergab mit den genannten Schwefelverbindungen 3.7, 2.8, 13.0, 0.9 und 1.8·10–16 ch3/s. Eine elektronenfangende Verbindung der Thiole mit NO2 wurde beobachtet.
  相似文献   

18.
We present the crystal and molecular structure of two key compounds of a new synthesis strategy for isomers of natural (2S,3R,4S)‐4‐hydroxyisoleucines, 2,3,5,6,7,8‐hexa­hydro‐3‐(1‐hydroxy‐1‐methyl‐2‐oxo­propyl)‐6,8‐methano‐7,7,8a‐tri­meth­yl‐5H‐1,4‐benzoxazin‐2‐one, C16H23NO4, and 2,3,5,6,7,8‐hexa­hydro‐3‐(1‐methyl‐2‐oxo­propyl)‐6,8‐methano‐7,7,8a‐tri­meth­yl‐5H‐1,4‐benzoxazin‐2‐one, C16H23NO3. A new optically pure chiral oxazinone auxiliary derived from (1R,2R,5R)‐2‐hydroxy­pinan‐3‐one was used.  相似文献   

19.
In the title compound, trans‐[CoCl(NO2)(C2H8N2)2]NO3, a distorted octahedral CoIII complex shows an orientational disorder such that the positions of the nitro and chloro ligands are exchanged. The occupation factors of the major and minor orientations are 84 and 16%, respectively. The O atoms of the nitrate ion are disordered over two sites.  相似文献   

20.
The title compound, {[Cu(NO3)(C2H4N2)(C10H8N2S2)(H2O)]NO3·H2O}n, is composed of a one‐dimensional linear coordination polymer involving cis‐protected copper(II) ions and a 4,4′‐dithiodipyridine bridging ligand. The polymeric chains run along the c‐axis direction. N—H...O and O—H...O hydrogen bonds involving the coordinating amine groups, nitrate ions and water molecules, as well as cocrystallized noncoordinating nitrate ions and water molecules, generate a three‐dimensional structure.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号