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Xiaoshuai Ren,1,* Feng Lin,2,* Chaogang Tang,2,* Yao Liu,3 Guolei Liao,2 Jiabi Liang,3 Wenji Luo,3 Lei Zhang,2 Wenli Chen3 1Department of Clinical Laboratory, The Fifth Affiliated Hospital of Sun Yat-Sen University, Zhuhai, Guangdong, 519000, People’s Republic of China; 2Department of Cerebrovascular Disease, The Fifth Affiliated Hospital of Sun Yat-Sen University, Zhuhai, Guangdong, 519000, People’s Republic of China; 3Department of Pharmacy, The Fifth Affiliated Hospital of Sun Yat-Sen University, Zhuhai, Guangdong, 519000, People’s Republic of China*These authors contributed equally to this workCorrespondence: Wenli Chen; Lei Zhang, Tel +15626471884 ; +13726209240, Email chenwenl@mail3.sysu.edu.cn; zhangl92@mail.sysu.edu.cnPurpose: Stroke is a leading cause of disability and death globally. However, there are few clinical drugs for stroke therapy. Novel and effective neuroprotectants are called on the way.Methods: In this study, 93 steroids from a constructed steroidal library were randomly numbered and blindly evaluated in an L-glutamate-induced HT-22 oxidative stress model. The neuroprotective effects of 5 candidates were further investigated in potassium deprivation-induced apoptosis of cerebellar granule neurons (CGNs), D-glutamate-induced excitotoxicity of CGNs, and cortical neuron (CN) models.Results: Interestingly, unblinding revealed that cholest-4-ene-3,6-dione (78), a cholesterol derivative, was first found to have comprehensive neuroprotective effects in all cell models. 78 administration also decreased the infarction volume and improved motor function in middle cerebral artery occlusion (MCAO) model rats. Additionally, 78 treatment decreased intercellular reactive oxygen species (ROS) and NO production in the HT-22 cell model. Finally, lipidomics and molecular docking results showed that 78 may exert its neuroprotective effects by increasing platelet-activating factor (PAF) analog 1-(9Z-pentadecenoyl)-glycero-3-phosphocholine production.Conclusion: This study indicates that 78, a novel neuroprotectant, is a promising therapeutic candidate with comprehensive neuroprotective effects for the treatment of ischemic stroke by decreasing ROS/reactive nitrogen species (RNS) levels and increasing 1-(9Z-pentadecenoyl)-glycero-3-phospho-choline production. Keywords: neuroprotection, cholest-4-ene-3,6-dione, anti-ROS, lipidomics, molecular docking

A new imidazo[4,5-f][1,10]phenanthroline (imp) derivative imidazo-N5,N6-bis((4-(1H-imidazo[4,5-f][1,10]phenanthroline-2-yl)phenyl)methylene)-1,10-phenanthroline-5,6-diamine (impap) was synthesized in five steps starting from bare phenanthroline (phen) precursors. The novel compound was fully characterized by 1H-NMR, IR, elemental analysis and electrospray ionization mass spectroscopy (ESI-MS) techniques. Solid state emission spectrum of impap showed two distinct strong emission maxima with large Stokes shifts. The ground state gas phase geometry of impap was predicted by DFT calculations. Excited state properties of the molecule were examined through TD-DFT calculations conducted at the optimized geometry. Responsible transitions for the strong fluorescence of impap were assigned to single component charge transfer transitions with large oscillator strengths based on the ground state calculated molecular orbital contributions.

The synthesis of previously unreported pyrazolo-pyrimidinones and isoxazolo-pyrimidinones are achieved via metal-free coupling of oxazine-2,6-diones with pyrazolidinone and isoxazolidinone, respectively. The synthesis provides easy access to a variety of novel 2- dimensional building blocks that can be derivatized to generate a range of drug- and agro-like molecules. [ABSTRACT FROM AUTHOR]

• Inhaled pan-PDE inhibitors decrease inflammation in OVA-induced allergic asthma. • Inhaled comp. 38 and 145 diminish airway remodeling in OVA-induced allergic asthma. • Inhaled comp. 38 and 145 reduce TGF-β/Smad signaling in OVA-induced allergic asthma. • Inhaled pan-PDE inhibitors act as dual anti-inflammatory and anti-remodeling agents. Asthma is a heterogeneous, chronic respiratory disease characterized by airway inflammation and remodeling. Phosphodiesterase (PDE) inhibitors represent one of the intensively studied groups of potential anti-asthmatic agents due to their affecting both airway inflammation and remodeling. However, the effect of inhaled pan-PDE inhibitors on allergen induced asthma has not been reported to date. In this study we investigated the impact of two, representative strong pan-PDE inhibitors from the group of 7,8-disubstituted derivatives of 1,3-dimethyl-3,7-dihydro-1 H -purine-2,6-dione: compound 38 and 145 , on airway inflammation and remodeling in murine model of ovalbumin (OVA)-challenged allergic asthma. Female Balb/c mice were sensitized and challenged with OVA, 38 and 145 were administrated by inhalation, before each OVA challenge. The inhaled pan-PDE inhibitors markedly reduced the OVA-induced airway inflammatory cell infiltration, eosinophil recruitment, Th2 cytokine level in bronchoalveolar lavage fluid, as well as both, total and OVA-specific IgE levels in plasma. In addition, inhaled 38 and 145 decreased many typical features of airway remodeling, including goblet cell metaplasia, mucus hypersecretion, collagen overproduction and deposition, as well as Tgfb1 , VEGF, and α-SMA expression in airways of allergen challenged mice. We also demonstrated that both 38 and 145 alleviate airway inflammation and remodelling by inhibition of the TGF-β/Smad signaling pathway activated in OVA-challenged mice. Taken together, these results suggest that the investigated pan-PDE inhibitors administered by inhalation are dual acting agents targeting both airway inflammation and remodeling in OVA-challenged allergic asthma and may represent promising, anti-asthmatic drug candidates. [ABSTRACT FROM AUTHOR]

The traditional spectrophotometric determination of stability constants of complexation involves finding a wavelength at which only one of the components has absorbance without any spectroscopic interference of the other reaction components. But this method fails when there is not selective wavelength for at least one of the component. Multivariate data analysis involving soft and/or hard model analysis can be used in these cases. In the present work, firstly, multivariate curve resolustion-alternative least squares which is a model free analysis, was used to estimate the chemical model of data variation and then a robust multi-wavelength model-based method has been developed to determine the stability constants of formed complex(s) regardless to the spectra overlapping of the components. By applying such model, not only the stability constants of the formed complex(s) can be calculated, but also the pure spectra of all contributed components are extracted well. The complexations of 1,10-phenanthroline-5,6-dione ligand with several metalic cations [Cu(II), Ni(II), Co(II), Zn(II)] were studied using proposed multi-wavelength spectrophotometric method in non-aqueous solution at 25 °C. It was found that there is a 2:1 stoichiometry between ligand with studied metalic cations and also their stability constants were calculated. DOI: http://dx.doi.org/10.4314/bcse.v28i3.6

While polymer acceptors are promising fullerene alternatives in the fabrication of efficient bulk heterojunction (BHJ) solar cells, the range of efficient material systems relevant to the 'all-polymer' BHJ concept remains narrow, and currently limits the perspectives to meet the 10% efficiency threshold in all-polymer solar cells. This report examines two polymer acceptor analogs composed of thieno[3,4- c]pyrrole-4,6-dione (TPD) and 3,4-difluorothiophene ([2F]T) motifs, and their BHJ solar cell performance pattern with a low-bandgap polymer donor commonly used with fullerenes (PBDT-TS1; taken as a model system). In this material set, the introduction of a third electron-deficient motif, namely 2,1,3-benzothiadiazole (BT), is shown to (i) significantly narrow the optical gap ( Eopt) of the corresponding polymer (by ≈0.2 eV) and (ii) improve the electron mobility of the polymer by over two orders of magnitude in BHJ solar cells. In turn, the narrow-gap P2TPDBT[2F]T analog ( Eopt = 1.7 eV) used as fullerene alternative yields high open-circuit voltages ( VOC) of ≈1.0 V, notable short-circuit current values ( JSC) of ≈11.0 mA cm−2, and power conversion efficiencies (PCEs) nearing 5% in all-polymer BHJ solar cells. P2TPDBT[2F]T paves the way to a new, promising class of polymer acceptor candidates. [ABSTRACT FROM AUTHOR]

An efficient, large-scale synthesis of piperazine-2,6-dione was developed. The advantages of this procedure include the use of inexpensive starting materials, satisfactory yields, and a convenient workup without the need for chromatographic techniques. Furthermore, this procedure can be easily modified for the preparation of 1-substituted piperazine-2,6-dione hydrobromides. The utility of the prepared piperazine-2,6-dione was demonstrated in the synthesis of a novel analogue of the only drug used in clinical practice to prevent anthracyclineinduced cardiotoxicity, dexrazoxane. [ABSTRACT FROM AUTHOR]

A series of novel p-type conjugated copolymers, PTTVBDT, PTTVBDT-TPD, and PTTVBDT-DPP, cooperating benzo[1,2-b:4,5-b0]dithiophene (BDT) and terthiophene-vinylene (TTV) units with/without thieno[3,4-c]pyrrole-4,6-dione (TPD) or pyrrolo[3,4-c]pyrrole-1,4-dione (DPP) via Stille polymerization were synthesized and characterized. Copolymer PTTVBDT shows a low-lying HOMO energy level and ordered molecular-packing behavior. Furthermore, two terpolymers, PTTVBDT-TPD and PTTVBDT-DPP, display stronger absorption ability, alower-lying HOMO energy level, and preferred molecular orientation, due to the replacement TTV-monomer units with electron-deficient groups. Furthermore, bulk-heterojunction organic solar cells were fabricated using blends of the PTTVBDT-TPD, and PC61BM gave the best power conversion efficiency of 5.01% under the illumination of AM1.5G, 100mW·cm-2; the short circuit current (Jsc) was 11.65 mA·cm-2 which displayed a 43.8% improvement in comparison with the PTTVBDT/PC61BM device. These results demonstrate a valid strategy combining the two-dimensional molecular structure with random copolymerization strikes promising conjugated polymers to achieve highly efficient organic photovoltaics. [ABSTRACT FROM AUTHOR]

Several 1,3-diaryl-5-(cyano-, aminocarbonyl- and ethoxycarbonyl-)-2-pyrazoline, pyrrolo[3,4-c]pyrazole-4,6-dione and 1,3,4,5-tetraaryl-2-pyrazoline derivativeswere prepared by the reaction of nitrilimine with different dipolarophilic reagents. The newcompounds were characterized using IR, 1H-NMR, 13C-NMR and mass spectra. Biologicalscreening of some compounds is reported.

Here, a conjugated polymer VTTPD based on thieno[3,4-c]pyrrole-4,6-dione (TPD) and dithiophene with vinyl as linker is synthesized and characterized. Electrochemical and optical studies indicate the LUMO and HOMO energies of the polymer are −3.70 and −5.39 eV. Theoretical calculation with density functional theory suggests that H-bonds are formed between the TPD carbonyl (O) and its neighboring vinyl (H) which benefit the planarity and π-conjugation of the polymer backbone. Bottom contact bottom gate organic field effect transistor devices based on VTTPD are fabricated and examined in air. After annealing at 160 °C, the devices exhibit excellent performance of μh = 0.4 cm2 V−1 s−1, Ion/off = 106, Vth within −10 V to −5 V. Thin film morphologies before and after the annealing process are also investigated with XRD and AFM. [ABSTRACT FROM AUTHOR]

Polymers based on thieno[3,4-c]pyrrole-4,6-dione derivatives are interesting and promising candidates for organic bulk heterojunction solar cells. Herein, a series of push-pull conjugated polymers based on thieno[3,4-c]pyrrole-4,6-dione (TPD), furo[3,4-c]pyrrole-4,6-dione (FPD), and selenopheno[3,4-c]-pyrrole-4,6-dione (SePD) have been synthesized by direct heteroarylation polymerization and fully characterized. The impacts of both the heteroatom (sulfur, oxygen, and selenium) and the side chain (branched or linear) of [3,4-c]pyrrole-4,6-dione unit on the electro-optical properties have been investigated. Among polymers developed, two new highly processable terthiophene-SePD (P4) and dithienosilole-SePD ( P9) copolymers led to airprocessed polymer solar cells with power conversion efficiencies of 5.1% and 7.1% using the following inverted configuration: ITO/ZnO/Polymer:PCBM/MoO3/Ag. These promising results make P4 and P9 good candidates for further upscaling and device optimization. [ABSTRACT FROM AUTHOR]

Novel 1-phenyl-piperazine-2,6-diones were prepared by a new facile synthetic routeusing methyl N-substituted iminomonoacetate as starting material. The structures of thesecompounds were established by 1H-NMR, 13C-NMR and GC/MS. 2-(4-Chloro-5-cyclo-pentyl-oxy-2-fluorophenyl)-tetrahydro-2H-pyrido-[1,2-a]-pyrazine-1,3-(4H,6H)-dione displayed thegreatest herbicidal activity.

Herein we report saturated and unsaturated fatty acid derivatives of 1,3,4- oxadiazol-2(3H)-one and tetrahydropyridazine-3,6-dione as new potential anticancer agents. All the synthesised compounds were characterised by IR, 1H-NMR, 13C-NMR, and mass spectral data. The relative sensitivity of three cancer cell lines varied depending on the nature of the compound. Among the most effective anticancer compounds studied, 3b and 6b displayed remarkable anticancer activity against the MDA-MB-231 and KCL-22 lines, respectively. On the other hand, compound 3c was found to be most sensitive to nearly all the tested cell lines, MDA-MB-231, KCL-22, and HeLa. [ABSTRACT FROM AUTHOR]

Searching for new promising metal-based drugs for the treatment of parasitic diseases against Trypanosoma cruzi, three related oxidovanadium(IV) complexes, [VIVO(SO4)(H2O)2(NN)], with the phenanthroline derivatives (NN) 1,2,5thiadiazolo[3,4- f]1,10phenanthroline (tdzp), 1,10-phenanthroline-5, 6-dione (phendione), and 5,6-epoxy-5,6-dihydro-1,10-phenanthroline (epoxyphen) are synthesized, characterized, and evaluated in vitro as anti- T. cruzi agents. The compounds are characterized in the solid state and in solution by elemental analysis, electrospray ionization mass spectrometry (ESI-MS), conductimetric measurements, and infrared (FTIR), UV/Vis, and electronic paramagnetic resonance (EPR) spectroscopy. EPR spectroscopy suggests that the ligands act as bidentate, binding through both nitrogen donor atoms in an axial-equatorial mode. DFT calculations corroborate the structural assignments. The stability of the complexes in solution is evaluated by EPR and 51V- NMR spectroscopy and all complexes show reasonable stability. The anti- T. cruzi activity of the complexes was tested by measuring the growth inhibitory effect on the epimastigote life cycle form of the parasite (Dm28c strain). All complexes show IC50 values in the micromolar range against T. cruzi and display activities of the same order of that of Nifurtimox, but lower than that of the previously reported analogue [VIVO(SO4)(H2O)2(dppz)] (dppz = dipyrido[3, 2-a:2′,3′-c]phenazine). Furthermore, DNA was evaluated as a potential target by using atomic force microscopy (AFM), showing that the complexes display ability to interact with this biomolecule. [ABSTRACT FROM AUTHOR]

A novel and efficient route to thieno[3,4-c]pyrrole-4,6-dione (TPD) facilitating late-stage alkylation is presented. Four copolymers with alkylated bithiophene (2T) are synthesised, with different TPD N-alkyl side-chain branching points. The effect of steric bulk on solid-state properties is investigated (UV-VIS, differential scanning calorimetry, X-ray diffraction) and C1-branching found to increase crystallinity and solid-state packing in TPD-2T. [ABSTRACT FROM AUTHOR]

Abstract: The electrochemical reduction process of 1,10-phenanthroline-5,6-dione (pdon) is chemically irreversible in pure aqueous solution at high pH values (pH >3.6) due to the formation of insoluble reduzate, 1,10-phenanthroline-5,6-diol (pdol), which gets away from the electrode surface and avoids being re-oxidized. This issue may be circumvented by adsorption of pdon on carbon nanotubes (CNTs) electrode. The adsorbed redox couple (pdon/pdol) well keeps its reversible electrochemical behavior even the pH value is expanded to 9.0. Thereby, it is possible to investigate the redox reaction mechanism of pdon/pdol in not only acidic but neutral and alkaline media as well. Interestingly, the reduction of pdon undergoes three distinct reaction paths and gives rise to variant reductive forms at different pH regions. The absorbed pdon also exhibits excellent electrocatalytic activity towards the oxidation of ascorbic acid (AA). The over potential is significantly lowered, which makes it possible to selective measurement of AA in the presence of dopamine (DA) and uric acid (UA). [Copyright &y& Elsevier]

Oxidation of low-density lipoprotein (LDL) is the principal risk factor for the development of atherosclerosis. In this study, we used several methods to investigate the ability of the acetone extract from rhizomes, stems, leaves, flowers, pericarps and seeds of Alpinia zerumbet to inhibit atherosclerosis in vitro. The seed extract had the strongest activity against tyrosinase, pancreatic lipase (PL), 15-lipoxygenase (15-LO) and LDL oxidation activities (IC50 = 2.30 ± 0.02, 5.00 ± 0.07, 1.29 ± 0.07 and 15.40 ± 0.86 μg/mL, respectively), amongst all different parts. It also had similar effects to the positive controls. Most of the extracts showed partial agonistic properties towards estrogenic activity. Cholest-4-ene-3,6-dione, a steroid present only in the seed extract seems to be the compound responsible for these activities. The results showed that cholest-4-ene-3,6-dione had similar ability to curcumin and quercetin against PL and LDL oxidation (IC50 = 19.50 ± 1.17 and 16.12 ± 1.43 mg/mL, respectively). Furthermore, cholest-4-ene-3,6-dione (IC50 = 34.21 ± 1.31 mg/mL) had higher inhibition against 15-LO than quercetin (IC50 = 54.79 ± 1.12 μg/mL). [ABSTRACT FROM AUTHOR]

A set of 13 alkyl derivatives of 3-phenylpiperidine-2,6-dione were synthesized. Newly obtained compounds were investigated in vitro against HIV-1 and other selected viruses. The benzyl 3f and fluorophenyl 3g derivatives showed moderate protection against CVB-2 and the compound 3g also against HSV-1. Derivatives were tested also for their antibacterial and antifungal activity. The molecular structures of 3a and 3d were determined by an X-ray analysis. [ABSTRACT FROM AUTHOR]

The reactions of the methoxybenzylidene derivatives of 2,2-dimethyl-1,3-dioxane-4,6-dione and their saturated analogs with potassium hydroxide in methanol, ammonia, and hydrazine hydrate were realized. The 1,2-bis(methoxybenzylidene)hydrazines, amides, and hydrazides of methoxybenzylidene-malonic acid, suitable for use as structural blocks in the synthesis of various structures based on them, were prepared and characterized. [ABSTRACT FROM AUTHOR]

Reactions of four reducing radical species namely e, H-atoms, (CH3)2 •COH and •CO radicals with [Co(III)(phendione)2Cl2]Cl (complex) have been studied by electron pulse radiolysis. Time resolved transient absorption spectra for all the four species show two peaks which match with those of phendione anion radical produced by the reaction of e with phendione. However, there are some differences in the spectral and kinetic features in the reactions of H-atoms and •CO radicals with the complex which are elaborated. Steady state absorption spectra on irradiation under reducing conditions indicate breakdown of the complex. The anion radical initially produced has fairly long lifetime of few 100 microseconds. Spectral studies show that initial site of attack for electron transfer is the phendione moiety. Subsequently the electron is transferred to other sites resulting in aquation/decomposition to metal ion. Conductometric studies show that conductance substantially increases on irradiation and could be attributed to aquation/de-ligation of the complex by intramolecular electron transfer. [ABSTRACT FROM AUTHOR]

The three component reactions of Meldrum's acid, 1,3-bis-(benzotriazol-1-yl)propan-2-one or 1-benzotriazol-1-ylpropan-2-one and an aldehyde, carried out in DMF at 60 °C gave rise to 2,4-bis-(benzotriazol-1-yl)cyclohexane-1,3-diones or 4-benzotriazol-1-ylcyclohexane-1,3-diones, respectively, in fairly high yields. Unlike similar reactions reported earlier with acetone, the reactions with 1,3-bis-(benzotriazol-1-yl)propan-2-one and 1-benzotriazol-1-ylpropan-2-one proceeded via an intramolecular acylation of the other methyl group of acetone. [ABSTRACT FROM AUTHOR]

[1,3]Dioxane-4,6-diones with (azulen-1-yl)methylene attached to position 5 were obtained by condensation of azulene-1-carbaldehydes with Meldrum's acid. The reaction was performed either neat or in absolute ethanol using a base as a catalyst. The involvement of the generated C=C bond either in electrophilic or radical reactions appears to be restricted. The advanced molecular polarization of the obtained products can account for the low reactivity of this bond. With the electrophilic reagents only the 3-position of azulenyl moiety was substituted. The azulene acylation with acetylsalicyloyl chloride occurred with rearrangement of the acyl chloride and, the formed products are 4H-1,3-benzodioxin-4-ones where azulen-1-yl moiety occupies the position 2 of the heterocyclic system. [ABSTRACT FROM AUTHOR]

Abstract: Using zinc triflate, the direct one-pot double cyclodehydration of linear tripeptides to the total synthesis of pyrazino[2,1-b]quinazoline-3,6-diones (1a–l) on solid support was achieved with good overall yields in short reaction time. These syntheses of the pyrazino[2,1-b]quinazoline-3,6-diones were conveniently achieved in only three steps, starting from the amino acid-bound Wang resin. [Copyright &y& Elsevier]

Abstract: The synthesis and the characterization of several mono- and dinuclear middle transition metal derivatives of 1,10-phenanthroline-5,6-dione, 1, are presented. The reaction of 1 with CrCl2(THF)2 gives CrCl2(O,O′-C12H6N2O2)(THF)2, 2, while the halides of iron(II), cobalt(II) and nickel(II) afford adducts of general formula MX2(N,N′-C12H6N2O2), M=Fe, 4, Co, 5, X=Cl; M=Ni, 6, X=Br. DFT calculations on CrCl2(L)(THF)2 with L= O,O′-C12H6N2O2 or O,O′-C14H8O2 allowed a direct comparison of the coordination properties of 9,10-phenanthrenequinone and 1,10-phenanthroline-5,6-dione to be made. Dinuclear compounds of general formula CrCl2(THF)2(O,O′-C12H6N2O2-N,N′)MX n L m , M=Zr, 7, X=Cl, n =4, m =0; M=Cr, 8, X=Cl, n =2, L=THF, m =2; M=Fe, 9, Co, 10, X=Cl, n =2, m =0; M=Ni, 11, X=Br, n =2, m =0, are prepared from 2 and the corresponding metal halide, while VCp2(O,O′-C12H6N2O2-N,N′)FeCl2, 12, is synthesized by reacting 4 with VCp2. The electronic properties of the different complexes are investigated by magnetic moment measurements and EPR spectroscopy. [Copyright &y& Elsevier]

Abstract: Three new α,α′-diimine ligands were synthesized based on condensation of 1,10-phenanthroline-5,6-dione with 1,2-phenylenediamine derivatives using different approaches. All compounds were fully characterized by IR, 1H and 13C NMR, UV–visible, and MS spectroscopies. We report the first example of a dipyrido[3,2-f:2′,3′-h]quinoxalino[2,3-b]quinoxaline, which exhibits a strong absorption at 430nm and an interesting electrochemical behavior. These new molecules may have biological potential and are of synthetic and technological importance. [Copyright &y& Elsevier]

A new analytical method based on reversed-phase high performanc liquid chromatography (HPLC) was developed and validated for the assay of benzo[f]quinoline-5,6-dione and the determination of its synthetic impurities by employing the method in liquid chromatography-mass spectrometry (LC-MS) with electrospray ionization (ESI) and photodiode array (PDA) UV detection. Separation was performed on a Waters Xterra C18 (150 mm×4.6 mm, 5 µm) column. UV detection was performed at 262 nm. The results showed that benzo[f]quinoline-5,6-dione is eluted as a spectrally pure peak resolved from its impurities. 1H-indeno[2,1-b]pyridine-2,9-dion and benzo[f]quinoline are identified as the main impurities. The proposed method was extensively validated and satisfactory results were obtained in terms of linearity (r2=0.9997) and precision (RSD<0.61%) in all cases. The limits of detection and quantification were 2 µg/mL and 20 µg/mL, with a 0.88% RSD, respectively. [ABSTRACT FROM AUTHOR]

Abstract: The novel cyclometalated Rh(III) complex, , where is pyridine-2-yl-2-phenyl and phen-dione is 1,10-phenanthroline-5,6-dione has been prepared and characterized by elemental analysis, IR, 1H NMR, and electronic absorption spectroscopies, cyclic voltammetry, and X-ray crystallography. The crystal structure of shows that the coordination geometry around the Rh(III) is a distorted octahedron, with bite angles of 76.13°–81.09° for all three bidentate ligands. [Copyright &y& Elsevier]

Abstract: Three new five-coordinate CuII complexes, [Cu(tpy)(phen-dione)](PF6)2, [Cu(phen)(phen-dione)Cl]PF6 and [Cu(bpy)(phen-dione)Cl]PF6 (tpy=2,2′;6′,2″-terpyridine, phen=1,10-phenanthroline and phen-dione=1,10-phenanthroline-5,6-dione) have been prepared and characterized by elemental analysis, IR and UV–Vis spectroscopies and cyclic voltammetry. The complex of [Cu(tpy)(phen-dione)](PF6)2 crystallized with one molecule of acetonitrile. The ortep drawing of [Cu(tpy)(phen-dione)](PF6)2 ·CH3CN shows that the coordination geometry around CuII is a distorted trigonal- bipyramid. Due to the steric hindrance of in the unit cell, the tpy ligands in each complex cation cannot interact in a π–π fashion. The effective magnetic moment (μ eff) of the complexes was measured by the Evans method. The cyclic voltammograms at Pt disk electrode for these complexes display only one reversible Cu(II)/Cu(I) redox couple. [Copyright &y& Elsevier]

Abstract: The anti-cancer chemotherapeutic potential of 1,10-phenanthroline-5,6-dione (phendione), [Cu(phendione)3](ClO4)2·4H2O and [Ag(phendione)2]ClO4 were determined using four human cells lines, i.e. two neoplastic (A-498 and Hep-G2) and two non-neoplastic (CHANG and HK-2). All of the phendione derivatives induced a concentration-dependant decrease in the viability of the four cell lines, with [Cu(phendione)3](ClO4)2·4H2O displaying greatest activity. In comparative studies, IC50 values obtained with the two neoplastic cell lines showed a cytotoxic response which was between 3 and 35 times greater than that observed for the metal-based anti-cancer agent, cisplatin. Furthermore, metal–phendione complexes, rather than simple solvated metal ions, were responsible for the observed cytotoxicity. Despite the high level of potency associated with these compounds they did not display an apparent cyto-selective profile, as they reduced the viability of both neoplastic and non-neoplastic cells. However, selected mechanistic studies showed that phendione and its metal complexes inhibited DNA synthesis which did not appear to be mediated through intercalation. Ames testing highlighted that all three compounds and their phase I metabolites were non-mutagenic, unlike cisplatin. Taken together, these results suggest that phendione and its Cu(II) and Ag(I) complexes may be capable of acting as highly effective anti-cancer therapies, which with careful administration could provide very potent and effective alternatives to cisplatin. [Copyright &y& Elsevier]

Two silver(I) coordination complexes of 1,10-phenanthroline-5,6-dione (pdon), [Ag2(pdon)2(ClO4)2] (1) and [Ag(pdon)2](CF3SO3) (2), have been synthesized and characterized by elemental analysis, IR, and X-ray diffraction analysis. Using AgClO4 with pdon, the central silver(I) is bridged by ligand pdon with two N and one O atoms and lead to the one-dimensional (1D) chain structure in 1. When triflate anion is used as a counter ion in 2, the silver(I) is chelated by two ligands with four N atoms, and then the molecular unit is linked by intermolecular hydrogen bond to afford a novel two-dimensional (2D) network architecture. [ABSTRACT FROM AUTHOR]

Abstract: Studies toward the construction of functionalized piperidone derivatives from derivatives of Baylis–Hillman adducts are described. Interestingly the 6-oxo-4-aryl-piperidine-3-carboxylates generated during the study serve as precursor for the facile synthesis of 4-oxo-6-aryl-3-aza-bicyclo[3.1.0]hexane-1-carboxylates. [Copyright &y& Elsevier]

Abstract: The synthesis and the characterization of several mono- and polymetallic derivatives of 1,10-phenanthroline-5,6,-dione (1) are presented.The reaction of 1 with M(CO)6 (M=Cr, Mo) gives compounds of general formula M(O,O′-C12H6N2O2)3, M=Cr (2), Mo (3).Compound 3 is also obtained starting from Mo(η6-CH3C6H5)2, whereas the reaction of Cr(η6-CH3C6H5)2 with 1 affords the ionic derivative [Cr(η6-CH3C6H5)2][C12H6N2O2] (4), which has been studied by EPR spectroscopy and DFT calculations.FeCl2(N,N′-C12H6N2O2)2 (6), is obtained by thermal decomposition of [Fe(N,N′-C12H6N2O2)3]Cl2 (5).Polymetallic compounds of general formula Cr[O,O′-C12H6N2O2-N,N′-MCl4]3,containing chromium and a Group 4 element M=Ti (7), Zr (8), Hf (9), are prepared from Cr(O,O′-C12H6N2O2)3 and the corresponding MCl4 or MCl4DME. Polynuclear derivatives of iron and chromium of formula [Fe(N,N′-C12H6N2O2-O,O′-CrCl2(THF)2)3][PF6]2 (10), and Cr[O,O′-C12H6N2O2-N,N′-FeCl2(THF)]3 (11), are obtained by the reaction of [Fe(N,N′-C12H6N2O2)3][PF6]2 with three equivalents of CrCl2(THF)2 and from Cr(O,O′-C12H6N2O2)3 and FeCl2(THF)1.5, respectively. Compound 11 reacts with 1 (3 equivalents in sym-C2H2Cl4 or 6 equivalents in ethanol) to give Cr[O,O′-C12H6N2O2-N,N′-FeCl2(N,N′-C12H6N2O2)]3 (12), and [Cr(O,O′-C12H6N2O2-N,N′-Fe(N,N′-C12H6N2O2)2)3]Cl6 (13), respectively. [Copyright &y& Elsevier]

Abstract: Regioselective desymmetrization of 4-substituted pyridazin-3,6-diones using sterically hindered 2,4,6-triisopropylphenyl-sulfonylchloride allowed efficient sequential palladium cross-coupling reactions. [Copyright &y& Elsevier]

Abstract: A three-component condensation reaction between an isocyanide, an electron-deficient acetylenic ester and (ethoxycarbonylmethyl)triphenylphosphonium bromide efficiently provides fully substituted N-alkyl-2-triphenylphosphoranylidene glutarimides in a one-pot reaction without any activation or modification. [Copyright &y& Elsevier]

Abstract: During the search for second-generation adenosine A1 receptor antagonist alternatives to the clinical candidate 8-(3-oxa-tricyclo[3.2.1.02,4]oct-6-yl)-1,3-dipropyl-3,7-dihydro-purine-2,6-dione (BG9719), we developed a series of novel xanthines substituted with norbornyl-lactones that possessed high binding affinities for adenosine A1 receptors and in vivo activity. [Copyright &y& Elsevier]

Abstract: A series of organic–inorganic composite films were prepared by the layer-by-layer self-assembly method containing the phendione complexes of transition metals [M(phendione)3]2+ (M=Fe2+, Co2+, phendione=1,10-phenanthroline-5,6-dione) and the polyoxometalates (POMs). UV–vis spectroscopy was used to follow the fabrication process of (BW12/[M(phendione)3]2+) n (BW12=BW12O40 5−, M=Fe2+, Co2+) and (Co4(PW9)2/[M(phendione)3]2+) n (Co4(PW9)2=Co4(H2O)2(PW9O34)2 10−, M=Fe2+, Co2+) multilayer films. Electrochemical studies on the films illustrate that the POM species exhibit well-defined redox peaks and the phendione species show pH-dependent electrochemical behavior. The photoluminescent properties were investigated to show the (BW12/[Fe(phendione)3]2+) n film with low-energey red photoluminescence at 672nm. [Copyright &y& Elsevier]

Abstract: Steroids with 4-ene-3,6-dione functionality have application in natural product chemistry, as synthetic intermediates and as aromatase inhibitors. Here, we report a two-phase oxidation of a range of steroidal 5-en-3β-ols into corresponding 4-ene-3,6-diones using a modified Jones oxidation. The new reaction affords high yields (77–89%) of product in relatively short reaction times (1–2h). The simplicity of this reaction gives significant advantages over previously reported methodologies. [Copyright &y& Elsevier]

Herein we present the synthesis and application of a prominent polymer solar cell (PSC) donor-acceptor (D-A) based material (PBDTHTPD) constituted of thiophene -benzo [1, 2-b: 4, 5-b′] dithiophene (BDT) and thienopyrroledione (TPD) as a potential active layer for organic thin film transistor (OFETs) application. The material synthesized via microwave stille coupling was characterized and applied as an active layer in a PMMA gated OFET device. Intrinsically, the polymer exhibits appreciable thermal steadiness of 382 °C, and showed UV–vis spectrum ranging from 300 nm up to 800 nm, affording an optical band gap of 1.86 eV. Energy level of this material assessed by cyclic voltammetry analysis showed both HOMO and LUMO levels of −4.98 eV and −3.12 eV, respectively for this novel organic semiconductor. Top-Gate/Bottom Contact (TG-BC) layout, based on the polymer demonstrated a p-type characteristics with maximum field-effect mobility (μ max) of 9.68 × 10−5 cm2v−1s−1. [ABSTRACT FROM AUTHOR]

β-Sitosterol and the new phytosteroid 24 S-ergost-4-en-3,6-dione were isolated from the industrial extraction waste of the alkaloid-bearing plant Aconitum septentrionale Koelle. The structure of the isolated compound was determined by x-ray structure analysis and PMR, C NMR, and IR spectroscopy. The crystal structure of the steroid contains a disordered terminal 24-methyl,24-isopropyl group that occupies two positions in a 0.55:0.45 ratio. [ABSTRACT FROM AUTHOR]

Abstract: In the course of the synthesis of γ-pyrones, well-known inhibitors of photosystem II electron transport, it turned out that the starting material, acyl derivatives of 2,2-dimethyl-1,3-dioxane-5,6-dione (Meldrum''s acid) are potent inhibitors of photosystem II electron transport. Thus, in a simple one-step synthesis from commercial available substances, highly potent photosystem II inhibitors are generated. The biological activity of the acyl derivatives is in a parabolic fashion dependent from the length of the alkyl side chain. [Copyright &y& Elsevier]

Quinones such as 1,4-naphthoquinones are abundant in nature and naphthoquinone based natural products are known to possess anticancer activity. This pharmacophore is known to convey anticancer activity to some drugs such as streptonigrin, mitomycin A, etc . We synthesized and characterized different classes of naphthoquinone derivatives including bis naphthoquinone, 2-arylaminonaphthoquinone, benzoxantene-6,11-dione and benzoacridine-5,6-dione derivatives instead of the expected 2-hydroxy-3-(substituted phenyl(aryl amino)methyl)naphthalene-1,4-dione derivatives from the reaction of 2-hydroxy1,4-naphthoquinone (lawson) with different benzaldehydes and aryl amines. Benzoacridine-5,6-dione derivatives and related imines showed potent anti-breast cancer activity in MCF-7 cancer cells. The in-vitro results revealed that five compounds benzoacridinedione derivatives ( 6b and 7b ) and imines ( 13 , 14 and 15 ) by the IC 50 range of 5.4-47.99 μM are the most potent anti-breast cancer structures.