Key indicatorsSingle-crystal X-ray study T = 293 K Mean (C-C) = 0.005 Å R factor = 0.048 wR factor = 0.129 Data-to-parameter ratio = 12.5For details of how these key indicators were automatically derived from the article, see

A new, efficient and green protocol for the nano-Cu 2 O-catalyzed homo-coupling reaction of terminal alkynes has been developed, using water/ionic liquid as an environmentally friendly solvent. Moreover, the system also allows the synthesis of unsymmetric 1,3-diynes by cross-coupling of two different terminal alkynes. It is noteworthy that the nano-Cu 2 O-catalyzed methodology is a good supplement to copper catalyst for the Glaser-type homo-coupling reaction.Additional supporting information may be found in the online version of this article at the publisher's web site. Scheme 2. Nano-Cu 2 O-catalyzed coupling reaction of 1-ethynylbenzene and 1-ethynyl-4-methoxybenzene.Scheme 3. Possible mechanism for the nano-Cu 2 O-catalyzed coupling reaction of terminal alkyne.

Eukaryotic topoisomerase 2 (Top2) and one of its interacting partners, topoisomerase II␤ binding protein 1 (TopBP1) are two proteins performing essential cellular functions. We mapped the interacting domains of these two proteins using co-immunoprecipitation and pulldown experiments with truncated or mutant Drosophila Top2 with various Ser-to-Ala substitutions. We discovered that the last 20 amino acids of Top2 represent the key region for binding with Mus101 (the Drosophila homolog of TopBP1) and that phosphorylation of Ser-1428 and Ser-1443 is important for Top2 to interact with the N terminus of Mus101, which contains the BRCT1/2 domains. The interaction between Mus101 and the Top2 C-terminal regulatory domain is phosphorylation-dependent because treatment with phosphatase abolishes their association in pulldown assays. The binding affinity of N-terminal Mus101 with a synthetic phosphorylated peptide spanning the last 25 amino acids of Top2 (with Ser(P)-1428 and Ser(P)-1443) was determined by surface plasmon resonance with a K d of 0.57 M. In an in vitro decatenation assay, Mus101 can specifically reduce the decatenation activity of Top2, and dephosphorylation of Top2 attenuates this response. Next, we endeavored to establish a cellular system for testing the biological function of Top2-Mus101 interaction. Top2-silenced S2 cells rescued by Top2⌬20, Top2 with 20 amino acids truncated from the C terminus, developed abnormally high chromosome numbers, which implies that Top2-Mus101 interaction is important for maintaining the fidelity of chromosome segregation during mitosis.

In the title heteronuclear ZnII–HoIII complex (systematic name: {μ-6,6′-dimeth­oxy-2,2′-[ethane-1,2-diylbis(nitrilo­methyl­idyne)]diphenolato-1κ4 O 1,O 1′,O 6,O 6′:2κ4 O 1,N,N′,O 1′)-μ-nitrato-1:2κ2 O:O′-dinitrato-1κ4 O,O′-holmium(III)zinc(II)), [HoZn(C18H18N2O4)(NO3)3], with the hexa­dentate Schiff base compartmental ligand N,N′-bis­(3-methoxy­salicyl­idene)ethyl­enediamine (H2 L), the Ho and Zn atoms are triply bridged by two phenolate O atoms of the Schiff base ligand and one nitrate ion. The five-coordinate Zn atom is in a square-pyramidal geometry with the donor centers of two imine N atoms, two phenolate O atoms and one of the bridging nitrate O atoms. The HoIII center has a ninefold coordination environment of O atoms, involving the phenolate O atoms, two meth­oxy O atoms, two O atoms from two nitrate ions and one from the bridging nitrate ion. Weak inter­molecular C—H⋯O inter­actions generate a two-dimensional double-layer structure.

The asymmetric unit of the unexpected title compound, 2,2,6,6‐tetra‐n‐butyl‐2,6‐dichloro‐4,8‐bis{[(1E)‐4‐methoxybenzylidene]hydrazino}‐1,5‐diaza‐2,6‐distanna‐3,7‐dithiabicyclo[3.3.0]octa‐3,7‐diene bis{1,5[(1E)‐4‐methoxybenzylidene]thiocarbonohydrazide} ethanol disolvate, [Sn2(C4H9)4Cl2(C18H18N6O2S2)]·2C17H18N4O2S·2C2H5OH, comprises one half‐molecule of the organotin complex, one thiocarbonohydrazide molecule and one ethanol solvent molecule, and is the first example of a substituted C2N2S2Sn2 planar dicyclo–organotin complex. Each SnIV atom is pentacoordinated with a distorted trigonal–bipyramidal geometry and the complex is disposed across a crystallographic centre of inversion. Weak intermolecular N—H...Cl and C—H...Cl hydrogen bonds and weak S...S interactions link the molecules of the organotin complex into one‐dimensional infinite chains.