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Interaction of [Pt(µ -Cl)(arylolefin)] 2 with either quinoline (Q) or four derivatives (N , O H) afforded 2 – 10. The N atom of Q and (N , O) are at the cis position with respect to the allyl group in all the complexes. The cytotoxicity of 4 against Lu and 5 against KB cell lines are approximately 6 and 4 times lower than cisplatin, respectively. [Display omitted] Nine new cyclometalated platinum(II) complexes of the formula [PtCl(arylolefin)(Q)] (2 , 3) and [Pt(arylolefin)(N , O)] (4 – 10) (arylolefinH: eugenoxyacetic acid, isopropyl eugenoxyacetate; Q: quinoline; (N , O H): quinolin-8-ol, 2-methylquinolin-8-ol, 5,7-dichloroquinloin-8-ol and quinoline-2-carboxylic acid] were synthesized and fully characterized by EA, ESI mass spectrometry, IR and NMR spectroscopy and single-crystal X-ray diffraction for 3 , 7 and 10. The results show that the arylolefin binds with PtII via the C5 atom of the phenyl ring and the C C allyl in all the synthesized complexes. Quinoline coordinates with PtII via its N atom in 2 , 3 , while deprotonated (N , O H) coordinates with PtII via both the N and O atoms in 4 – 10. The N atom of Q and (N , O) in all complexes are at the cis position with respect to the allyl group of the arylolefin. The XRD confirms the square-planar coordination of PtII and trans position of the arylolefin and quinoline ligands. The results of in vitro cytotoxicity tests against human cancer cell lines KB and Lu of 2, 4 – 8 indicate that 4 and 5 exhibit the highest activities against Lu and KB cell lines with the IC 50 values of 7.1 and 4.1 µM, respectively, which are approximately 6 and 4 times lower than cisplatin. [ABSTRACT FROM AUTHOR]

[Display omitted] A series of complexes between bis(2-pyridyl)-di(4- n -butylphenyl)ethene (KT4) and bis(2-pyridyl)-di(3-methoxyphenyl)ethene (KT18) with transition metals Co(II), Cu(II), Zn(II), and Cd(II) were synthesized and crystallized. The structures of these compounds were confirmed based on IR, NMR, and MS spectra. Moreover, crystals were obtained for ZnKT18, CoKT18, CuKT18, CdKT18, and CdKT4. Single-crystal X-ray diffraction (XRD) demonstrated the ability of these pyridine-based ligands to coordinate to metal ions via two nitrogen atoms in the aromatic heterocycles. Depending on the central metal, they can form different structures. Zn(II) and Co(II) form mononuclear complexes with KT18 , where the metal coordinates to two N atoms and two chloride ions in a tetrahedral geometry (coordination number 4). The complexes CuKT18 , CdKT18 , and CdKT4 are binuclear complexes with one pendant chloride and two bridging chlorides coordinating with the metal ion (coordination number 5). The cytotoxic properties of free ligands and complexes were tested on four cancer lines, including KB, Hep-G2, Lu, and MCF-7. In general, the free ligands have no cytotoxic activity, while all complexes present strong to medium effects on these cancer lines. Several complexes are comparable in activity to cisplatin, a commercial drug used in the treatment of cancer. Specifically, ZnKT4 selectively inhibits the activities of the KB and Hep-G2 cell lines. CdKT4 has a high impact on Hep-G2 and Lu (IC 50 < 5 μM) while CdKT18 exhibits effective anticancer activity against the KB and MCF-7 cell lines. CuKT18 strongly inhibits the growth progress of the KB cancer cell (IC 50 = 9.52 μM). These IC 50 values are lower than those of cisplatin. [ABSTRACT FROM AUTHOR]

Abstract: A novel bidentate ligand, H8-BIFOL, was successfully prepared and resolved starting from readily available reagents. The reactivity and selectivity was evaluated in the alkynylation of benzaldehyde, resulting in ee’s up to 56%. [Copyright &y& Elsevier]

Abstract: The reaction of molybdate and dl-proline at pH 3.4 results in the formation of a Na4[Mo8O26(proO)2]·22H2O complex (pro=proline) in which two proline ligands are attached to molybdenum(VI) ions via monodentate coordination of the carboxylate groups. The structure of the complex was determined by single crystal X-ray diffraction and by combination of 1H, 13C and 95Mo NMR spectroscopy techniques in solution. The structure of the complex is strongly dependant on the pH. At native pH 3.4 the octamolybdate-type structure seems to be present in solution, but the increase of pH to 5.8 resulted in a rearrangement of the structure to a heptamolybdate-type structure. At physiological pH, the polyoxometalate framework was completely dissociated into the monomeric unit. The reactivity of the Na4[Mo8O26(proO)2]·22H2O towards the hydrolysis of ATP was tested at different pH values. While in solution at pH 3.4 the hydrolysis proceeded to yield AMP (adenosine monophosphate) and ADP (adenosine diphosphate) in nearly equal amounts, reaction mixture at pH 5.8 gave ADP as the only product of hydrolysis after 24h of reaction. At neutral pH, the hydrolysis of ATP was slower, but it proceeded to yield 75% of ADP after 48h of reaction. [Copyright &y& Elsevier]

• A novel palladium catalysis to prepare C4-substituted phenanthridinones via N-arylation/aryl-aryl coupling. • Excellent chemo- and regioselectivity, functional group tolerance and moderate to excellent yield. • Further late-stage diversification of products for the synthesis of multiple-substituted phenanthridinones. An excellent chemo- and regioselective palladium-catalyzed cascade intermolecular N -arylation/aryl-aryl coupling process has been developed. Employing Pd(TFA) 2 , PCy 3 •HBF 4 , K 2 CO 3 and 1,4-dioxane in an oil bath at 100°C for 12 h, diverse C4-substituted phenanthridinones are synthesized from o -bromobenzamides in 42-92% yield. Broad substrate scope and excellent functional group tolerance are observed. The synthetic utility of this method is illustrated by the further derivatization to prepare multiple-substituted phenanthridinones in 30-75% yield. [Display omitted] [ABSTRACT FROM AUTHOR]

Protein phosphatase-1 (PP1) is a major protein Ser/Thr phosphatase in eukaryotic cells. Its activity depends on two metal ions in the catalytic site, which were identified as manganese in the bacterially expressed phosphatase. However, the identity of the metal ions in native PP1 is unknown. In this study, total reflection X-ray fluorescence (TXRF) was used to detect iron and zinc in PP1 that was purified from rabbit skeletal muscle. Metal exchange experiments confirmed that the distinct substrate specificity of recombinant and native PP1 is determined by the nature of their associated metals. We also found that the iron level associated with native PP1 is decreased by incubation with inhibitor-2, consistent with a function of inhibitor-2 as a PP1 chaperone. [ABSTRACT FROM AUTHOR]

A two-step one-pot sequence, involving Ugi reaction followed by base-promoted carbocyclization accompanied by cleavage of the isocyanide-originated amide moiety, has been successfully elaborated in order to provide a fast access to 6,7-dihydro-5 H -pyrrolo[3,4- b ]pyridin-5-ones. When the cyclizations were run under air atmosphere a subsequent oxidation occurred producing oxidized 7-hydroxy-6,7-dihydro-5 H -pyrrolo[3,4- b ]pyridin-5-ones. [ABSTRACT FROM AUTHOR]

• A gold-catalyzed cascade annulation of peptidomimetics and oligopeptides for the synthesis of highly functionalized pyrrolo[1,2- b ]isoquinolines. • Tandem 6-endo-dig cyclization/enyne cycloisomerization/1,2-migration cascade. • Excellent chemo- and regioselectivity, functional group tolerance. A chemo- and regioselective gold-catalyzed tandem 6-endo-dig cyclization/enyne cycloisomerization/1,2-migration process for the synthesis of decorated peptidomimetics is developed. Various migrating groups such as aryl, heteroaryl and alkyl are tolerated in this method under mild conditions. This protocol is successfully utilized to modify various oligopeptides, including substrates bearing the drug amantadine, in a rapid and step-economical manner through the combination with the Ugi reaction. [Display omitted] [ABSTRACT FROM AUTHOR]

Abstract: 5-Diazoimidazoles and 5-diazopyrazoles have been shown to react with acyl isothiocyanates yielding the imidazo- and pyrazolo[5,1-d][1,2,3,5]thiatriazines stabilized by a nonbonded S⋯O interaction. In contrast to acyl isothiocyanates, alkyl-, aryl-, and arylsulfonyl isothiocyanates do not react with 5-diazoazoles. The nature and the strength of stabilizing intramolecular interaction between non-bonded S and O atoms have been studied by X-ray analysis for mono crystals and DFT calculations for selected azolo[5,1-d][1,2,3,5]thiatriazines. The interaction was described in terms of Weinhold covalence ratio factors, NBO, and AIM schemes. The reaction discovered was used to develop an efficient approach toward the new 8-substituted 4-ethoxycarbonylimino-4-benzoyl- and 4-(3,4,5,6-tetrafluorobenzoyl)iminoimidazo(pyrazolo)[5,1-d][1,2,3,5]thiatriazines. [Copyright &y& Elsevier]

Abstract: Chiral imidates were efficiently synthesized in one step and with high yields (seven examples). These chiral imidates were used as ligands in the Cu(I)-catalyzed asymmetric aziridination of methyl cinnamate and in the asymmetric diethylzinc additions to benzaldehyde as a proof of principle. The imidate catalyst system showed high catalytic activities and induced encouraging selectivities. An X-ray structure analysis of an imidate-Cu(I) complex is included, showing a distorted tetrahedral arrangement with two bidentate ligand molecules surrounding the metal. [Copyright &y& Elsevier]

Abstract: Reaction of 3-alkylsulfanyl-2-arylazo-3-(pyrrolidin-1-yl)acrylonitriles with maleimides, dimethyl maleate and dimethylacetylene dicarboxylate were carried out to give octahydro-pyrrolo[3,4-a]pyrrolizin-4-ylidenes, hexahydro-pyrrolizines and 6,7-dihydro-5H-pyrrolizines. The formation of the synthesized compounds is explained by a 1,3-dipolar cycloaddition of an in situ generated azomethine ylide. The mechanisms of the formation of these active intermediates were discussed with the aid of density functional theory methods with the B3LYP functional 6-31G+ calculations using the STQN method and chemical experiments. [Copyright &y& Elsevier]

Abstract: The complex formed by the reaction of the uranyl ion, UO2 2+, with bromide ions in the ionic liquids 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ([Bmim][Tf2N]) and methyl-tributylammonium bis(trifluoromethylsulfonyl)imide ([MeBu3N][Tf2N]) has been investigated by UV–Vis and U LIII-edge EXAFS spectroscopy and compared to the crystal structure of [Bmim]2[UO2Br4]. The solid state reveals a classical tetragonal bipyramid geometry for [UO2Br4]2− with hydrogen bonds between the Bmim+ and the coordinated bromides. The UV–Vis spectroscopy reveals the quantitative formation of [UO2Br4]2− when a stoichiometric amount of bromide ions is added to UO2(CF3SO3)2 in both Tf2N-based ionic liquids. The absorption spectrum also suggests a D4h symmetry for [UO2Br4]2− in ionic liquids, as previously observed for the [UO2Cl4]2− congener. EXAFS analysis supports this conclusion and demonstrates that the [UO2Br4]2− coordination polyhedron is maintained in the ionic liquids without any coordinating solvent or water molecules. The mean U–O and U–Br distances in the solutions, determined by EXAFS, are, respectively, 1.766(2) and 2.821(2)Å in [Bmim][Tf2N], and, respectively, 1.768(2) and 2.827(2)Å, in [MeBu3N][Tf2N]. Similar results are obtained in both ionic liquids indicating no significant influence of the ionic liquid cation either on the complexation reaction or on the structure of the uranyl species. [Copyright &y& Elsevier]

Abstract: A convenient synthesis of substituted pyrazino[1,2-a]benzimidazol-1(2H)ones starting from 3,5-dichloropyrazinones has been accomplished. Various 3-anilino-pyrazinones were easily converted to the desired tricyclic structures by applying a microwave assisted Buchwald–Hartwig type cyclization. [Copyright &y& Elsevier]

Abstract: An unprecedented route for the synthesis of N-1 substituted 5-(phenylsulfanyl)-1,4-dihydropyrazine-2,3-diones is disclosed starting from 5-chloro-3-(phenylsulfanyl)pyrazin-2(1H)-ones. The method comprises treatment of various 5-chloro-3-(phenylsulfanyl)pyrazin-2(1H)-ones with Na2CO3 in water under microwave irradiation providing the respective 5-(phenylsulfanyl)-1,4-dihydropyrazine-2,3-diones in good yields, via hydrolysis of the thioether bond and subsequent nucleophilic displacement of the chlorine by the in situ generated thiophenol. The obtained compounds are excellent precursors for the diversity oriented synthesis of pharmacologically active α,β-dicarbonyl compounds. [Copyright &y& Elsevier]

Abstract: The near-infrared luminescence properties of three (E)-N-hexadecyl-N′,N′-dimethylamino-stilbazolium tetrakis(1-phenyl-3-methyl-4-benzoyl-5-pyrazolonato) lanthanide(III) complexes are described. These three complexes, containing trivalent neodymium, erbium and ytterbium, respectively, show near-infrared luminescence in acetonitrile solution upon UV irradiation. Luminescence decay times have been measured. The complexes consist of a positively charged hemicyanine chromophore with a long alkyl chain and a tetrakis(pyrazolonato) lanthanide(III) anion. Because of the absence of an α-hydrogen atom in the pyrazolonato ligands, and because of the saturation of the coordination sphere by four bidentate ligands, the luminescence properties are enhanced when compared to, e.g. quinolinate complexes. [Copyright &y& Elsevier]

Abstract: The systematic study of oxidative cyclization of 3-hydrazono-1,3-dihydroindole-2-thiones has been carried out and a series of new 2H-[1,2,3]thiadiazolo[5,4-b]indoles has been prepared. The elaborated reaction represents an efficient method for the synthesis of fused 1,2,3-thiadiazoles. [Copyright &y& Elsevier]

Intramolecular cyclization of 1-amino-3-phenacyl-4-carbohydrazido-1,2,3-triazolium-5-olates has been shown to take place via selective interaction of the carbonyl group with the terminal amino function of the hydrazido group to form a 1,2,5-triazepine ring. Minor products, resulting from the interaction of the α-nitrogen atom of the hydrazido group with the carbonyl function, having a N-amino-pyridazine structure were also detected and isolated. A general method for the synthesis of novel mesoionic 2-amino-7-aryl-4-oxo-2,4,5,8-tetrahydro[1,2,3]triazolo[5,1-d][1,2,5]triazepin-9-ium-3-olates was developed. [Copyright &y& Elsevier]

Two new trachylobane- and one isopimarane-type diterpenoids: ent-18-hydroxy-trachyloban-3-one; ent-trachyloban-3-one; isopimara-7,15-dien-3β-ol, were isolated from the leaves of Croton zambesicus, together with trans-phytol, β-sitosterol, α-amyrin and stigmasterol. The structures were determined by extensive NMR techniques and X-ray analysis. The cytotoxicity of these compounds has been evaluated on cancer and non-cancer cell-lines. [Copyright &y& Elsevier]

Abstract: Synthesis of pharmaceutically important 1,5-disubstituted-4-haloimidazoles starting from α-aminonitriles is described. Some 1D and 2D NMR spectral features of these imidazoles are discussed. [Copyright &y& Elsevier]

Summary SDS22 is an ancient regulator of protein phosphatase-1 (PP1). Our crystal structure of SDS22 shows that its twelve leucine-rich repeats adopt a banana-shaped fold that is shielded from solvent by capping domains at its extremities. Subsequent modeling and biochemical studies revealed that the concave side of SDS22 likely interacts with PP1 helices α5 and α6, which are distal from the binding sites of many previously described PP1 interactors. Accordingly, we found that SDS22 acts as a "third" subunit of multiple PP1 holoenzymes. The crystal structure of SDS22 also revealed a large basic surface patch that enables binding of a phosphorylated form of splicing factor BCLAF1. Taken together, our data provide insights into the formation of PP1:SDS22 and the recruitment of additional interaction proteins, such as BCLAF1. Graphical Abstract Highlights • The LRRs of SDS22 interact with PP1 helices α5 and α6 • A basic surface patch of SDS22 binds phosphorylated BCLAF1 • Many PP1 holoenzymes contain SDS22 as a third subunit • SDS22 prevents the autodephosphorylation of PP1 The function of protein phosphatase 1 (PP1) is determined by associated regulatory proteins. Heroes et al. describe the structure of the PP1 regulator SDS22, which largely consists of leucine-rich repeats. They also present a biochemically validated model of the PP1:SDS22 complex and use it as a guide for functional studies. [ABSTRACT FROM AUTHOR]