Photo-induced Coupling Reaction of 1, 1-Diphenyl-2, 2-dicyanoethylene with 10-Methyl-9, 10-dihydroacridine

In a previous communication1, we reported a novel photo-induced coupling of 9-fluorenylidenemalononitrile 1 with the coenzyme NADH model 10-methyl-9, 10-dihydroacridine (AcrH2) to give 9-dicyanomethyl-9-(10-methyl-9-acridinyl)fluorene and proposed a mechanism involving photo-induced electron transfer-proton transfer and radical coupling. This is a scarce mechanism for the reaction of NADH models2, which usually takes place by a formal hydride transfer pathway3. In view of the novelty of t…     

Studies on Selena-Macrocyclic Amides Synthesis and Structural Characterization of 7-Phenyl-5, 9-dioxo-1-selena-4, 7, 10-triazacyclododecane and 6-(4-Nitrobenzyl )-5, 9-dioxo-1, 4, 7, 10-selenatriazacyclododecane

lmTR0DUCTI0NSincetheseleniumcoronandswereachivevedin1989tli,thesynthesisandcoor-dinationchemistrystudyofthismacrocycliccomPOundshavereceivedwideattentionowingtotheirstrongcomplexingabilitiestowardssoft.transiti0nandheavymetals.InourprevibuspaPer,wereP0rtedthecrystalstructureoftw0selenacrownethers(2'3)andaPd(1)complexwith10'selenabenzo-15-crown-5t4i.Duetothedifficultyofthepreparationsofselenium-nitr0genmixeddonorc0n-..tainingmacrocycles,thestudyontheseligandsisconsiderablyscarce.Thesynthes…     

反式9, 10-二氢-9, 10-二苯基-9, 10-菲二醇包结性能的研究

合成了一种具有螯形结构的反式-9, 10-二氢-9, 10-二苯基-9,10-菲二醇(1)作为主体分子。它能与许多有机小分子化合物, 诸如DMF, DMSO, 吡啶, 哌啶, 喹啉, 异喹啉等形成包结化合物。本文还报道了这些包结化合物的IR, 粉末XRD的表征, 用^1H NMR谱测定了它们的分子摩尔比。DMF包结物的单晶四圆X衍射结果表明主体分子1与客体分子形成的包结物为配位笼状包合物。     

反式-9, 10-二氢-9, 10-二(1-萘基)-9, 10-菲二醇的包合现象 与晶体结构

按文献方法合成了一个螯形主体分子,反式-9,10-二氢-9,10-二(1-萘基)-9,10-菲二醇。研究发现该主体可以和一些含氮杂环化合物形成一定比例的晶体包合物。用X-射线衍射分析二环己胺包合物的晶体结构表明,包合物中主客体之间存在O-H…N氢键相互作用,客体分子包合在主体分子形成的空腔中。     

Photoluminescence and Electroluminescence Properties of 2, 5-Bis[2,2′-bis （5-phenyl ）- 1, 3,4-oxadiazole] Thiophene （T-OXD） and T-OXD／Poly（9-vinylcarbazole） Blends

The photoluminescence(PL) and the electroluminescence(EL) properties of a novel organic compound, 2,5-bis (2,2‘-bis(5-phenyl)-1, 3,4-oxadiazole (T-OXD), were studied in chloroform and in a solid thin film. The PL and the EL properties of T-OXD/poly(9-vinylcarbazole)(PVK) blends were also studied, which contained various contents of T-OXD. The PL maximum emission peaks of T-OXD/PVK blends show gradual bathochromtic-shift with the increase of the T-OXD content. The EL spectra of T-OXD/PVK devices are similar to their PL spectra, and all the EL maximum emission peaks show bathochromtic-shift compared with the corresponding PL spectra, which is ascribed to the formation of electroplex. The turn-on voltages for ITO/T-OXD; PVK/AI devices decreased from 13.5 V of the device cotaining 0. 1% T-OXD(mass fraction) to 5 V of the device containing 5% T-OXD, which suggests that T-OXD improves the energy level match between T-OXD and PVK and enhances the emission efficiency. The experimental results indicate that T-OXD can be used as a good electron transporting material.     

Structures and stability of N9, N9 − and N9 + clusters

 Ab initio molecular orbital calculations for N₉, N⁻ ₉ and N⁺ ₉ isomers were carried out at the HF/ 6-31G*, B3PW91/6-31G*, B3LYP/6-31G* and MP2/ 6-31G* levels of theory. Stable equilibrium geometric structures were determined by harmonic vibrational frequency analyses at the HF/6-31G*, B3PW91/6-31G* and B3LYP/6-31G* levels of theory. The most stable free-radical N₉ cluster is structure 1 with C _{2 v} symmetry and that of anion N⁻ ₉ is structure 3 with C _s symmetry. Only one stable structure of the N⁺ ₉ cation with C _{2 v} symmetry was predicted. Their potential application as high-energy-density materials has been examined. Received: 15 June 1999 / Accepted: 11 October 1999 / Published online: 14 March 2000     

Synthesis and Fluorescence Quenching of Copolymer Containing3, 4, 9, 10-Perylenetetracarboxyl Diimide Side Chains

Inrecentyears,thestUdiesofvariousorganicphoto-luminousandphotoconductivematerialsusedinlightemittingdiodes(LED)"photodiodes,lightemittinelectrochemicalcells2'3andplasticlaser4havebeenanactiveareainboththeoreticalandpracticalresearch,Asphotosensitiveelectrontransfermaterial,polyvinylcarbazole(PVK)possessesslowpotentialitysinceithasonlyaslightsensitivityinthevisibleregion.However,itispossibletosensitizethephoto-conductionofPVKfilmbyadditionofasmallamountofcertaindyesorelectfonacceptorcompoun…     

Viscosities for Binary Mixtures of 1-Decanol, Hexane, and Diethylamine at 10, 25, and 40°C

Experimental viscosities provide information on the structure of liquids and are required in the design of processes, which involve fluid flow, mass transfer, or heat transfer calculations. This work reports experimental viscosity data of the binary mixtures: 1-decanol + hexane, 1-decanol + diethylamine, and hexane + diethylamine at 10, 25, and 40°C and atmospheric pressure for the whole range of compositions. The viscosities of the pure liquids and their mixtures were determined using Cannon Fenske viscometers thermostated at ±0.01°C. The estimated error in the measured viscosities was less than ±0.005 mPa-s. The dynamic viscosity and the excess energy of activation for viscous flow were also calculated. The equation of Redlich–Kister was used for fitting the excess properties of the binary mixtures. The excess viscosity shows positive deviations from ideal behavior for the mixtures 1- decanol + hexane and 1-decanol + diethylamine and a small negative deviation for the binary system hexane + diethylamine. The experimental results have been also used to test some empirical and semiempirical equations adopted previously to correlate viscosity composition data.     

Synthesis and antitumor activity of 9-methyl-10-hydroxycamptothecin

A novel camptothecin analogue, 9-methyl-10-hydroxycamptothecin （4）, was unexpectedly synthesized from 10-hydroxycamptothecin in two steps. The key step included an efficient Mannich-type reaction. The overall yield was 47.2%. An ether analogue of 4, 9-methyl-10-benzylaminomethoxycamptothecin （5）, was also prepared. These new camptothecin analogues were evaluated for in vitro cytotoxicity against four human cancer cell lines, and exhibited more potent antitumor activities than contrals camptothecin and topotecan against several cancer cells.     

Synthesis and Resolution of 10, 11-Dihydro- 10-hydroxycyproheptadine

10, 11-Dihydro-10-hydroxycyproheptadine was synthesized in a new and facile synthetic route and resolved by L-(-)-2-(1, 3)-dioxo-1, 3-dihydroisoindol-2-yl)-propionic acid and D-( )-tartaric acid, respectively. The free base of the two enantiomers has the same absolute specific rotation value.     

Synthesis, Structure and Characterization of Manganese（ Ⅱ ） Coordination Polymer with Camphoric Acid and 1, 10-Phenanthroline

IntroductionThe syntheses of metal-organic coordination poly-mers have been attracting increasing attention owing tothe potential applications of their functional materials incatalysis,non-linear optics,magnetism sensors andmolecular recognition[1—7].Coordination polymers crys-tallized from polyaromatic acids and metal-ions are ofgreat interest for their polymeric structures and porousproperties[8—12].Their network topologies based on mo-lecular building blocks are usually controlled and mod…     

Synthesis, Characterization, Crystal Structure and Stability of a Ternary Cu（Ⅱ） complex with 1, 10-Phenanthroline and L-Valinate

It is important to research the mixed-ligand copper complexes containing bioligands, such as amino acids, nucleic acids and proteins, in exploring the functional mechanism of microelement copper in organism because the reaction of any micronutrient with two or more bioligands in the concentrated bioligands background gives mixed-ligand ternary complexes, which are more stable and related with storage of substance and transportationof metal ions in the life process.     

Modeling of enzyme–substrate complexes for the metalloproteases MMP-3, ADAM-9 and ADAM-10

The matrix metalloproteases (MMPs) and the ADAMs (A Disintegrin And Metalloprotease domain) are proteolytic enzyme families containing a catalytic zinc ion, that are implicated in a variety of normal and pathological processes involving tissue remodeling and cancer. Synthetic MMP inhibitors have been designed for applications in pathological situations. However, a greater understanding of substrate binding and the catalytic mechanism is required so that more effective and selective inhibitors may be developed for both experimental and clinical purposes. By modeling a natural substrate spanning P4-P4' in complex with the catalytic domains, we aim to compare substrate-specificities between Stromelysin-1 (MMP-3), ADAM-9 and ADAM-10, with the aid of molecular dynamics simulations. Our results show that the substrate retains a favourable antiparallel beta-sheet conformation on the P-side in addition to the well-known orientation of the P'-region of the scissile bond, and that the primary substrate selectivity is dominated by the sidechains in the S1' pocket and the S2/S3 region. ADAM-9 has a hydrophobic residue as the central determinant in the S1' pocket, while ADAM-10 has an amphiphilic residue, which suggests a different primary specificity. The S2/S3 pocket is largely hydrophobic in all three enzymes. Inspired by our molecular dynamics calculations and supported by a large body of literature, we propose a novel, hypothetical, catalytic mechanism where the Zn-ion polarizes the oxygens from the catalytic glutamate to form a nucleophile, leading to a tetrahedral oxyanion anhydride transition state.     

Synthesis and Properties of Biodegradable Copolymers of 9-Phenyl-2, 4, 8, 10-tetraoxaspiro-[5, 5]undcane-3-one and Ethylene Ethyl Phosphate

Novel biodegradable copolymer poly（CC-co-EEP） was synthesized by ring-opening copolymerization of cyclic carbonate 9-phenyl-2, 4, 8, 10-tetraoxaspiro-[5, 5]undcane-3-one （CC） and ethylene ethyl phosphate （EEP）. The obtained poly （CC-co-EEP）s were characterized by FTIR, ^1H NMR, ^13C NMR and gel permeation chromatography （GPC）. In vitro hydrolytic degradation of the copolymers were investigated in phosphate buffer solution （pH=7.4）. Hydrophilic phosphate units apparently improved the degradability of poly（carbonate-phosphate）.     

Ab Initio Study of Prednisolone, 6α-Fluoroprednisolone, 9α-Fluoroprednisolone,and 6α,9α-Difluoroprednisolone

A theoretical study of prednisolone, 6-fluoroprednisolone, 9-fluoroprednisolone, and 6,9-difluoroprednisolone has been performed at the ab initio HF/6-31G, MP2/6-31G, and B3LYP/6-31G levels. Structural information and the electronic features of prednisolone and its derivatives and the synergistic effect of 6,9-difluoroprednisolone was examined. Contrary to the AM1 and MNDO results, we found 9-fluoroprednisolone is more stable than the 6-fluoroprednisolone. The increased corticosteroid activity of the 6,9-difluoroprednisolone is most likely due to electronic effects, mainly related to the receptor binding.     

Analysis of the vibronic structure of the 1A1g → 1B3g, 1B2u transition in biphenyl -h10 and -d10

The absorption spectra of biphenyl-h₁₀ and -d₁₀ crystals in the region of the ¹A_1g → 1B_3g, ¹B_2u transitions are interpreted in terms of vibronic coupling of the two closely spaced electronic states by six b_1u vibrations.     

Photoluminescence and Electroluminescence Properties of 2,5-Bis[2,2′-bis(5-phenyl)-1,3,4-oxadiazole] Thiophene(T-OXD)and T-OXD/Poly(9-vinylcarbazole) Blends

The photoluminescence(PL) and the electroluminescence(EL) properties of a novel organic compound, 2,5-bis(2,2′-bis(5-phenyl)-1,3,4-oxadiazole(T-OXD), were studied in chloroform and in a solid thin film. The PL and the EL properties of T-OXD/poly(9-vinylcarbazole)(PVK) blends were also studied, which contained various contents of T-OXD. The PL maximum emission peaks of T-OXD/PVK blends show gradual bathochromtic-shift with the increase of the T-OXD content. The EL spectra of T-OXD/PVK devices are similar to their PL spectra, and all the EL maximum emission peaks show bathochromtic-shift compared with the corresponding PL spectra, which is ascribed to the formation of electroplex. The turn-on voltages for ITO/T-OXD:PVK/Al devices decreased from 13.5 V of the device cotaining 0.1% T-OXD(mass fraction) to 5 V of the device containing 5% T-OXD, which suggests that T-OXD improves the energy level match between T-OXD and PVK and enhances the emission efficiency. The experimental results indicate that T-OXD can be used as a good electron transporting material.     

Synthesis,Crystal Structure and Prosperities of 10-（4,5-Dibenzylthio- 1,3-dithiol-2-ylidene）anthracen-9（10H）-one

The title compound 10-（4,5-dibenzylthio-1,3-dithiol-2-ylidene）anthracen-9（10H）- one （C31H22OS4） has been synthesized, and its crystal structure was prepared by crystallization from CH2Cl2-MeOH. The crystal belongs to the triclinic system, space group Pi with a = 10.9758（3）, b = 11.4241（4）, c = 11.7460（2）A^°, α = 62.379（2）, β = 81.227（3）, γ = 80.321（2）°, Mr = 538.73, V = 1281.69（7） A^°^3, Z = 2, Dc = 1.396 g/cm^3, F（000） = 560,μ = 0.395 mm^-1, the final R = 0.0291 and wR = 0.0739. The molecular structure is severely distorted from planarity. The central ring of anthraquinone moiety adopts a boat conformation, while the two outer benzene rings are tilted in the opposite direction to form a dihedral angle of 23.65°. The photocurrent generation was measured and an anodic photocurrent response was obtained. The electronic spectrum was studied by using TDDFr method on the basis of optimized geometries with B3LYP method. The obtained results are in good agreement with the experimental values.     

Synthesis and Thermal Decomposition Kinetics of the Complex of Samarium p-Methylbenzoate with 1 ,10-Phenanthroline

The complex [Sm（p-MBA）3phen]2 （p-MBA, p-methylbenzoate; phen, 1,10-phenanthroline） was prepared and characterized by elemental analysis, IR and UV spectra. The thermal decomposition process of [Sm（pMBA）3phen]2 was studied under a static air atmosphere by TG-DTG and IR techniques. Thermal decomposition kinetics was investigated employing a newly proposed method, together with the integral isoconversional non-finear method. Meanwhile, the thermodynamic parameters （AH#, △G# and AS#） were also calculated. The lifetime equation at mass-loss of 10% was deduced as In r=-24.7825＋ 18070.43/T by isothermal thermogravimetric analysis.     

Two New 9, 10-seco-Cycloartanes from the Seeds of Sphaerophysa salsula

Two novel compounds, named sphaerophyside SC and SD were isolated from the ethanolic extract of the seeds of Sphaerophysa salsula. The structures of the compounds were elucidated on the basis of the NMR data, especially the 2D NMR technique.