两个新颖的联环十二烷衍生物的合成及结构表征

2-（2＇-Oxo-3＇-oximidocyclododecyl） cyclododecanone （1） and 2-（1＇-hydroxylcyclododecyl） cyclododecanone （2） were synthesized and characterized. The conformation analysis was carried out based on the NMR, molecular mechanics calculation and X-ray diffraction. The conformation of two cyclododecyl moieties of both 1 and 2 was found to be the [3333]-2-one or [3333] square conformation both in the crystal state and the solution. The dihedral angle between carbonyl and the oxime double bond of the ring B is 180°in the crystal of 1. The protons or hydroxyl group of carbon atoms to link the two cyclododecyl moieties of 1 and 2 constitute dihedral angles of 174°in the crystal, and 175°in the solution, and the C-C 6 bond between two cyclododecyl moieties can not freely rotate in the solid state and the solution. In addition, compound 2 was the first example of a-comer-anti-monosubstituted cyclododecanone. synthesis     

Synthesis and Conformation Analysis of cis-1,2-Disubstituted Cyclododecanes

cis-1,2-Disubstituted cyclododecanes 2 were synthesized by sodium borohydride reduction of 2-monosubstituted cyclododecanones and their structures were confirmed by 1H- NMR, 13C NMR and elemental analysis. The higher cis-selectivity of NaBH4 reduction of 2- monosubstituted cyclododecanones was rationalized by the mode of “corner position carbonyl participation”. Crystal data for 2c: Mr = 263.21, monoclinic, space group P21/c, a = 1.11140(7), b = 2.62590(17), c = 0.91360(6) nm, β = 106.1840(10)°, V = 2.5606(3) nm3, Dc = 1.366 g/cm3, Z = 8, F(000) = 1104, μ(MoKα) = 3.182 mm-1, S = 0.837, the final R = 0.0460 and wR = 0.1033. Crystal X-ray diffraction analysis for 2c showed that its ring skeleton adopts [3333] conformation, in which the OH group presents at the side-exo position and the other one at the corner carbon. The 1H NMR data of 2 showed that 1-corner-R-2-side-exo-OH [3333] and 1-corner-OH-2-side- exo-R [3333] conformations coexist in dynamic equilibrium in the solution, but only the former presents in the crystal.     

Synthesis and Conformation of cis-1,2-Disubstituted Cyclododecene

Eight 1,2-disubstituted cyclododecenes were synthesized from a-alkoxycarbonyl-cyclododecanone and alkyl chloroformate. Their configuration and conformation determined by IR, NMR spectroscopy and X-ray diffraction analysis showed that the carbon-carbon double bond of all of the synthesized compounds has cis-configuration, and the ring skeleton of their preferred conformation is [lene2333] in solid, and they may adopt two different [lene2333] conformations, which exist in a dynamic equilibrium in solution.     

Chemoselective Bromodecarboxylation of α-Carboxy- α-cinnamoyl Ketene Cyclic Dithioacetals

α-Oxoketene dithioacetals（ compound 1 ） are versatile synthons for organic synthesis due to their specially structural characteristic, that is, the masked ketene is conjugated with the convertible carbonyl in their molecules. Although there have been numerous reports covering the reactions in which they have been taken as 1,3-electrophiles, the reaction at the α-carbon atom of α-oxoketene dithioacetals has seldom been investigated. Junjappa and co-workers found the α- bromination of compound 2 in the presence of NBS led to α-aroyl-α-bromo ketenedithioacetals. However, the flexibility of the functional groups at the α-carbon atom of compound 2 are still limited.     

Synthesis and Crystal Structure of Monocarbonyl Analogs of Curcumin

Two monocarbonyl analogs of curcumin containing bis(2,6-difluorobenzyl) were synthesized,and their molecular structures were characterized by 1H NMR,ESI-MS,and X-ray crystallography.In this paper,the crystal structures of these two analogs(A75 and C75) are described and compared with their bis(2-fluorobenzyl) analogues as well as with the available data of curcumin.The cyclopentane rings in A75 have an envelope conformation,while the cyclohexane ring in C75 has a chair conformation.The compounds are symmetrical and the central structure of A75 and C75 connects with two benzylidene rings through E,E-oriented double bonding.     

Crystal Studies and Antitumor Activities of Novel D-seco-taxoids Derived from 1-Deoxybaccatin Ⅵ

Two novel taxoids were synthesized from 1-deoxybaccatin Ⅵ and their crystal structures were determined by X-ray crystallographic techniques. The influences of oxetane ring on molecular conformations and bioactivity were investigated. The result shows that the oxetane ring plays an important role in the conformation and bioactivity of the diterpenoid core. In the structure of compound 3, the six-membered A ring exhibits the 1,4-di-planar conformation, the eightmembered B ring adopts a boat-chair conformation, and the six-membered C ring exhibits a slightly distorted half-chair conformation. However, in D-seco-taxoid 4, the six-membered C ring exhibits a boat conformation with the release of ring strain for the D-ring opening.     

Preparation and characterization of the crystalline inclusion complexes between cyclodextrins and poly(1,3-dioxolane)

The preparation and characterization of the crystalline inclusion complexes between a polymeric guest, poly(1,3-dioxolane) (PDXL), and small-molecular hosts, cyclodextrins (CDs) are reported. It is observed that the polymer guest can form crystalline inclusion complexes with three kinds of cyclodextrins, which may be attributed to the high oxygen atom density in PDXL chain. The crystalline inclusion complexes were characterized with FTIR , TGA, X-ray diffraction, SEM, 1H NMR and 13C CP/MAS NMR spectroscopes. It was found that the crystalline inclusion complexes have higher temperature stability than the pure CDs. The X-ray powder diffraction patterns of the crystalline inclusion complexes proved that they have columnar structures. 13C CP/MAS NMR spectra of the crystalline inclusion complexes indicate that CDs adopt a more symmetrical conformation in the complexes, while pure CDs assume a less symmetrical conformation in the crystal without a guest inside their cavities. The morphology of the crystal was     

Synthesis, Characterization and Crystal Structure of （Z）-1-[2-（Triarylstannyl）vinyl]-1-indanols and Their Arylhalostannyl Derivatives

(Z)-1-[2-(Tri-o-tolylstannyl)vinyl]-1-indanol (1) and (Z)-1-[2-(tri-p-tolylstannyl)vinyl]-l-indanol (2) were synthesized by the addition reaction of 1-ethynylindanol with tri-o-tolyltin and tri-p-tolyltin hydride. The aryl groups in compound 1 and 2 were substituted by Br2 or I2 to yield monohalide derivatives (3-6). The compounds 1-6 were characterized by elemental analysis, ^1H NMR and FT-IR spectroscopy. The crystal structures of 1, 2 and 4 have been determined by single crystal X-ray diffraction analysis. The Sn atom in 1 and 2 exhibits a tetrahedral geometry distorted towards trigonal bipyramid due to a weak intramolecular interaction between Sn and the hydroxyl O atoms [0.2839(4) nm and 0.2744(5) nm], while the Sn atom in 4 adopts a trigonal bipyramidal geometry with a significant O→Sn(1) interaction [0.2552(5) nm].     

Chemical inequivalence behavior of the protons attached to the same carbon in ethylene-propylene copolymer（EPC）

Six ethylene-propylene copolymer samples with different structural parameters were analyzed by ^1H NMR,^13C NMR and ^1H-^13C COSY in this paper.With the aid of the ^1H-^13C COSY spectra of ethylene-propylene copolymer,the chemical inequivalence behavior of the protons attached to the same carbon in the ethylene-propylene copolymer could be observed. Four basic types of chemical bonds were divided,and two kinds of main conformations were proposed to explain this phenomenon. Based on the calculation of conformation distribution,it can be proved that the explanation of this phenomenon was reasonable.     

Synthesis, Crystal Structure, Physical Properties, and Application of a Series of Functional Dibenzo[d,f][1,3]dioxepine Derivatives

The twisted aromatics, functional dibenzo[d,f][1,3]dioxepine derivatives were synthesized in high yields from reactions of 5,5＇-dibromo-2,2＇-biphenol with corresponding ketal or ketone compounds under acid catalysis. The structures of these compounds were characterized by ^1H NMR, elemental analysis, UV-Vis absorption spectrum and X-ray diffraction analysis. The conformation of O--C--O bridged biphenyl derivatives with varied substitute groups on 6,6＇-position was studied by X-ray crystallography and force-field simulation. The result of calculations by UNIVERSAL 1.02 force field in Cerius2 package（4.6） indicates that dibenzo[d,f][1,3]dioxepine derivatives show twisted conformations and the twisted angle between the phenyl rings is about 40°, which is accordant with the result from crystal structure determination, though the obtained angles in the crystal of dibenzo[d,f][1,3]dioxepine derivatives with the varied substitute groups on 6,6＇-position are shown to be slightly shifted to 40° owing to intermolecular interactions in crystal stacking. DSC studies exhibit that the substitute groups on 6,6＇-position can induce a large variation of endothermic peaks ranging from 80 to 135 ℃. The conjugated polymers based on dibenzo[d,f][1,3]dioxepine derivatives, which have ultraviolet emitting with a quantum efficiency of 10%, were obtained by Yamamoto coupling.     

a,a,a,b-ZnT(o-BocThr)APP对咪唑衍生物和氨基酸酯的分子识别研究

Molecular Recognition of α,α,α,β-ZnT（o-BocThr）APP （1） toward a series of imidazole derivatives and amino acid esters was investigated. Association constants were determined in chloroform by means of UV-Vis titration method. The association constants of 1 with imidazole derivatives are larger than those of 1 with amino acid esters. 1H NMR spectra were investigated to describe the binding mode of the recognition system, showing that all the protons of the guests were shifted to upfield. The circular dichroism spectra of 1-L-/D-ValOMe showed a split cotton effect in Soret region, while those of 1-L-/D-PheOMe showed no split cotton effect. Molecular modeling was performed to understand chiral recognition on a molecular level. Quantum chemical calculation was carried out based on the stable conformations of these recognition systems, which gave a reasonable explanation for the behavior of molecular recognition. The results indicated that the conformation of 1-D-ValOMe was more stable than that of 1-L-ValOMe.     

Stereoselective Synthesis of Sulfonyl-substituted trans-2,3-Dihydrofuran Derivatives via Reaction of Arsonium Ylides with α,β-Unsaturated Ketones

Trans-2,3-dihydrofuran derivatives 3 or 4 substituted with a sulfonyl group were prepared with high chemoselectivity and good yields by [1＋4]-addition reaction of α,β-unsaturated ketones 1 with arsonium bromide 2 in CH2Cl2 in the presence of potassium carbonate at room temperature.The structures of the products were characterized by IR,MS,^1H NMR,elemental analysis and single crystal X-ray diffraction analysis.A mechanism for the formation of products was also proposed.     

有机磷化合物的研究IX.某些具有活泼亚甲基化合物的碳磷酰化反应

The formation of P -- C bond is one of the important problems in synthetic organophosphorous chemistry. This paper describes the study of the formation of P -- C linkage via phosphorylation of carbon atom containing active hydrogen. p-Substituted phenylacetonitrile possessing an active methylene group undergoes stepwise C -- phosphorylation smoothly with diethyl phosphoryl chloride in the presence of naphthalene-sodium. Phosphonyl chloride reacts analogously. Being a deprotonizing agent naphthalene-sodium is distinguished by its availability, effectiveness and mild reaction conditions. The presence of an electron-withdrawing group in the benzene ring reduces the yield of phosphorylation seriously. The chemical shift of ^3^1P NMR of the resulted α-cyano-benzylphosphonates (1) correlates linearly with the Hammett \s\ constants of the substituents. As indicated by ^1H NMR studies the protons in the ester ethyl groups are magnetically nonequivalent. Compound 1 can be alkylated with alkyl halide or condensed with aromatic aldehyde by Hornor-Wittig type reaction due to the presence of active hydrogen atom. The structure-reactivity studies of diethyl phosphoryl chloride on reacting with various β- and β-diketones and β-keto esters (5) as regiospecific reaction were reported. The influences of metal ions in the enolates on the reactivity of the latter were examined and discussed. Only vinyl phosphates with predominantly Z configuration have been isolated exclusively. The C atom with an active hydrogen in the β-diketones investigated is inert to phosphorylation. These experimental results are well supported by reaction selectivity in terms of Eqo/Ecoc based on EHMO calculation.     

Two pairs of unusual scalemic enantiomers from Isatis indigotica leaves

Two pairs of unusual scalemic enantiomers with a novel carbon skeleton of 2-[1'-('-hydroxy-3',5'-dimethoxyphenyl)ethyl]-2-methoxyindolin-3-one, named isatidifoliumindolinones A–D(1–4), were isolated from an aqueous extract of Isatis indigotica leaves(da qing ye). Their structures including absolute configurations were determined by spectroscopic data analysis combined with comparison of their experimental CD and calculated ECD spectra. Validity of the ECD spectra calculation to assign the absolute configurations is discussed. Plausible biosynthetic pathways of 1–4 are proposed.Stereochemistry-dependent activity against LPS-induced NO production in BV2 cells was observed,and among the stereoisomers compound 4 is most active.     

Aminolysis reaction of calix [ 4 ] arene esters and crystal structures and conformational behaviors of calix[4]arene amides

We first make use of aminolysis of calix[4]arene esters to synthesize calix[4]arene amides. When the two ethyl esters of the calix[4]arene esters are aminolysized, the 1, 3-amide derivative is formed selectively. The crystal structures of the calix-[4]arene with two butyl amide (3b) and four butyl amide moieties (4b) were determined. The intermolecular hydrogen bonds make 4b form two-dimensional net work insolid state. The 1H NMR spectra prove that 3b is of a pinched cone conformation, while 4b and tetraheptylamide-calix[4]arene (6b) take fast interconversion between two C2v isomers in solution and appear an apparent cone conformation at room temperature. As decreasing temperature, the interconversion rate decreases gradually and, finally, the interconversion process is frozen at Tc = -10℃, which makes both conformations of 4b and 6b the pinched cone structures. The hydrogen bond improves the interconversion barrier, and the large different values of the potential barrier between 6b and 4b (or 6b) may     

Synthesis, Crystal Structure and Characterization of α-（1-Benzimidazolyl） -hypnone Cobalt（Ⅱ） Complex： [CoCl （ C7H5N2CH2COPh）4] Br

The crystal structure of [CoCl ( C7H5N2CH2COPh)4] Br has been determined by means of X-ray crystallography. The molecular structure consists of a discrete [CoCl ( C7H5N2CH2COPh)4] ^ cation and one Br^- anion, in the [CoCl ( C7H5N2CH2COPh)4]^ cation, the coordination geometry of the central Co atom is square-pyramidal with four tertiary N atoms of benzimidazole from four α-( benzimidazol-1-yl) -hypnone ligands in the basal position and one chloride anion in the apical position. In the solid state, [CoCl ( C7H5N2CH2COPh)4]^ and Br^- anion possess intermolecular and intramolecular interactions, which stabilize the crystal structure. The characterization of the title compound were also carried out by using elemeutal analysis, FTIR, UV spectrometries and TG-DSC.     

A Quantum Chemistry Study of Inhibition Properties of Imidazole and Its Derivatives on Iron Surface Corrosion

The geometries of imidazole and its derivatives were respectively optimized by using ab initio method, and the molecular orbital energy levels and the charge densities were obtained for their optimum geometries. The frontier orbital energy levels, and the net charges of N (1) atom and the imidazole ring of those molecules were obtained with ab initio and SCC-DV-Xα methods. It was found that the inhibition properties of those compounds change with the highest occupied molecular orbital energy levels, and the net charges of N (1) atom. We took four iron atoms on the crystal plane (100) of α-iron as the surface which was used to study the adsorption towards the inhibitors. The adsorption models of the inhibitor to be adsorbed on the Fe-cluster surface were optimized with SCC-DV-Xα method. It turns out that the most favorable model is that the inhibitor molecule is adsorbed on the Fe-cluster surface in an inclined state. The calculation shows that the stabilization energies of the systems are well correlated with the inhibition efficiencies.     

Syntheses and properties of photostable near-infrared cyanines and their cyclodextrin conjugates

Three fluorescent indocyanines containing p-carboxybenzyl groups on N atoms in the heterocyclic tings were synthesized under supersonic. The maxima wavelength of the absorption and emission of the dyes were 550-800 nm in water. Compared with those in aqueous solutions, the fluorescence intensity of the dyes in the α/β-cyclodextrin, Al^3＋, Zn^2＋, Sn^2＋ or the α/β-cyclodextrin in the aqueous solutions of the cations became stronger. The crystal Shapes of the dyes and their cyclodextrin inclusions were mostly acicular or polygon. The NHS-carboxyl squarylium indocyanine was prepared and used to conjugate with taurine or benzylamine, the results indicated that the dyes could couple covalently to biomass containing free NH2 group. Structure and some thermal parameters of the molecule of the trimethine cyanine were obtained by DFT method of Gaussian O3.     

具有U构型的二{1-甲硫基-1-[1-苯基-1-(1-苯基-3-甲基-5-氧代-4,5二氢吡唑-4-烯)-甲氨基]亚氨甲基}二硫醚的晶体结构

The reaction of 1-phenyl-3-methyl-4-benzoyl-2,5-dihydro-1H-pyrazol-5-one (PMBP) and methyldithiocarbazate (mdtc) in methanol results in formation of a yellow crystalline solid, adduct of 1-phenyl-3-methyl-4benzoyl-2,5-dihydro-lH-pyrazol-5-one and methyldithiocarbazate. When the yellow solids were dissolved in a mixture of methanol and ether (1:4), a red crystal, which is an oxidation product of the former, was obtained by allowing solvent to evaporate for a few days at room temperature. The X-ray analysis of the red crystal indicates that it is a novel disulfide with a special structure like a “U” conformation in the solid state.     

单氧代-二硒烷基-1, w-二氧取代杯[4]衍生物的合成,结构及萃取性能研究

Novel macrocyclic monooxa-diselkylene-1,ω-dioxy substituted calix[4]arene derivatives 1a-5a were synthesized by the reaction of calix[4]arene dibromides 1-5 with the disodium salt of bis（2-selenylethyl）ether in the yields between 28% and 64%. Their structures were characterized by proton and carbon NMR spectra. X-Ray structure analysis of la further confirmed the cone conformation of compounds 1a-5a. An interesting host-guest complex of la with dichloromethane via CH/π and C1/π interactions was elucidated. Extraction experiments showed that these novel monooxa-diselkylene-1,ω-dioxy substituted calix[4]arene derivatives 1a-5a had strong extraction ability towards mercury ion. The interaction of Hg^2＋with the calix ligand has also been investigated by 1^H NMR titration.