Bis[bis­(methoxy­carbimido)amine‐κ2N,N′]bis­(perchlorato‐κO)copper(II) bis­[bis­(methoxy­carbimido)amine‐κ2N,N′]bis­(methanol‐κO)copper(II) bis­(perchlorate) methanol disolvate

The title compound, [Cu(ClO₄)₂(C₄H₉N₃O₂)₂][Cu(C₄H₉N₃O₂)₂(CH₄O)₂](ClO₄)₂·2CH₃OH, comprises two independent Cu^II species lying on different inversion sites. In the Cu complexes, a distorted octa­hedral geometry arises (from basic square‐planar N₄ coordination) from the weak coordination of two perchlorate ions (as Cu—O) in one species and two methanol mol­ecules in the other (also as Cu—O). Inter­actions between the O atoms of the perchlorate anions or methanol groups and the imide or amine NH groups afford an extensive inter­molecular hydrogen‐bonding network.     

Two salts of 5‐sulfosalicylic acid and 3‐aminopyridine

5‐Sulfosalicylic acid (5‐SSA) and 3‐aminopyridine (3‐APy) crystallize in the same solvent system, resulting in two kinds of 1:1 proton‐transfer organic adduct, namely 3‐aminopyridinium 3‐carboxy‐4‐hydroxybenzenesulfonate monohydrate, C₅H₇N₂⁺·C₇H₅O₆S⁻·H₂O or 3‐APy·5‐SSA·H₂O, (I), and the anhydrous adduct, C₅H₇N₂⁺·C₇H₅O₆S⁻ or 3‐APy·5‐SSA, (II). Both compounds have extensively hydrogen‐bonded three‐dimensional layered polymer structures, with interlayer homo‐ and heterogeneous π–π interactions in (I) and (II), respectively.     

Pushing up the size limit of chalcogenide supertetrahedral clusters: two- and three-dimensional photoluminescent open frameworks from (Cu(5)In(30)S(54))(13-) clusters

Direct band gap copper indium chalcogenides are of great technological importance in part because of their high photovoltaic conversion efficiency. Covalent superlattices constructed from copper indium chalcogenide clusters are of particular interest because they may combine open framework architecture with semiconducting properties. Here two photoluminescent covalent superlattices built from core-shell type copper indium sulfide supertetrahedral clusters are reported. Each cluster consists of 35 metal cations and is so far the largest known supertetrahedral cluster with a metal-to-metal distance of 1.6 nm. In addition, this is the first example of supertetrahedral clusters in heterometallic copper indium chalcogenides. The preparation of these large clusters has narrowed down the size gap between colloidal nanoclusters and small supertetrahedral clusters and revealed new possibilities in the construction of nanoporous semiconducting superlattices with tunable pore size. Through the combination of metal ions with different oxidation states to provide both overall and local charge neutrality, an effective approach has been demonstrated in the rational synthesis of chalcogenide open framework materials with large and unprecedented supertetrahedral clusters.     

支化高分子在溶液中的交叠与缠结

溶液中高分子的交叠和缠结与其链结构密切相关。支化聚苯乙烯的临界交叠浓度C和临界缠结浓度C_E比分子量相同的线型聚苯乙烯的大,说明交叠和缠结同分子在溶液中线团的体积有直接关系。     

Electrochemical Synthesis and Characterization of Nickel(II) Complexes with N‐2‐Pyridyl‐sulfonamide Ligands

Heteroleptic nickel(II) complexes [NiL₂L′] of a series of monoanionic and potentially bidentate N‐2‐pyridyl‐sulfonamide ligands [HL] and 2,2′‐bipyridine or 1,10‐Phenanthroline (L′) have been prepared by electrochemical oxidation of a nickel anode in an acetonitrile solution of the ligands. The complexes have been characterized by microanalysis, IR and electronic spectroscopy, magnetic measurements and LSI mass spectrometry. The crystal structure of [Ni(Ms6mepy)₂(bipy)] has been determined by x‐ray diffraction and shows the metal in an octahedral NiN₆ environment. Octahedral structures are also proposed for the other complexes with the N‐2‐pyridyl‐sulfonamide ligands acting as N,N′ or N, O bidentate systems, depending on the position of the methyl substituent on the pyridine ring.     

Two‐Dimensional Holo‐ and Hemidirected Lead(II) Coordination Polymers: Synthetic,Spectroscopic, Thermal,and Structural Studies of [Pb(μ‐SCN)2(μ‐ebp)1.5]n and {[Pb(μ‐OAc)(μ‐ebp)](ClO4)}n (ebp=4,4′‐[(1E)‐Ethane‐1,2‐diyl]bis[pyridine]; OAc=Acetato)

Two new coordination polymers of Pb^II complexes with bridging 4,4′‐[(1E)‐ethane‐1,2‐diyl]bis[pyridine] (ebp), thiocyanato, and acetato ligands, [Pb(μ‐SCN)₂(μ‐ebp)_1.5]_n ( 1 ) and {[Pb(μ‐OAc)(μ‐ebp)](ClO₄)}_n ( 2 ), were synthesized and characterized by elemental analysis, FT‐IR, ¹H‐ and ¹³C‐NMR, thermal analysis, and single‐crystal X‐ray diffraction. In 1 , the Pb²⁺ ions are doubly bridged by both the ebp and the SCN⁻ ligands into a two‐dimensional polymeric network. The seven‐coordinate geometry around the Pb²⁺ ion in 1 is a distorted monocapped trigonal prism, in which the Pb²⁺ ions have a less‐common holodirected geometry. In 2 , the Pb²⁺ ions are bridged by AcO⁻ ligands forming linear chains, which are also further bridged by the neutral ebp ligands into a two‐dimensional polymeric framework. The Pb²⁺ ions have a five‐coordinate geometry with two N‐atoms from two ebp ligands and three O‐atoms of AcO⁻. Although ClO acts as a counter‐ion, it also makes weak interactions with the Pb²⁺ center. The arrangement of the ligands in 2 exhibits hemidirected geometry, and the coordination gap around the Pb²⁺ ion is possibly occupied by a configurationally active lone pair of electrons.     

C19-二萜生物碱贡乌生的结构研究

毛茛科植物贡嘎乌头 ( Aconitum liljestrandii)具有镇痛、镇静、祛风湿等功效 ,产于我国西藏东部及四川西部 [1] .我们从其块根中分得 1 8个单体 ,其中 1 6个为已知生物碱 [2 ,3] ,2个为新生物碱 [3] .本文报道新的 C19-二萜生物碱贡乌生 ( Liljestrandisine) 1的结构 .1　实验部分1 .1　仪器与试剂　 Boetius微量熔点测定仪 ;Nicolet FTIR2 0 0 SXV型红外光谱仪 ,KBr压片 ;BrukerAC- E2 0 0和 Varian Unity INOVA40 0 /5 4核磁共振仪 ,溶剂为 CDCl3,TMS为内标 ;VG Autospec30 0 0型和 VG70 A型质谱仪 ;Pekin Polarimete…     

High-throughput protein analysis by multiplexed sodium dodecyl sulfate capillary gel electrophoresis with UV absorption detection

We have developed a novel, high-throughput approach for molecular mass determination of proteins from 14 200 to 116 000 based upon multiplexed, absorbance-based capillary electrophoresis. Via capillary multiplexing, 96 samples were analyzed simultaneously within 30 min. Detection with ultraviolet light obviates the need for protein staining or derivatization. The detection limit of the system was estimated at 5 microg/ml bovine serum albumin (BSA) when sampled from 12.5 mM Tris-HCl. The linear dynamic range was over two orders of magnitude from 5 microg/ml to 1000 microg/ml for BSA. Better than 5% sizing accuracy for protein molecular mass determination and excellent run-to-run and day-to-day reproducibility was obtainable with the described method.     

New ent‐Abietanoids from Isodon rubescens

Six new ent‐abietane diterpenoids, rubescensins I–M ( 1 – 5 ) and P ( 6 ), along with two related acetonide derivatives ( 7 and 8 ), were isolated from Isodon rubescens. Their structures were elucidated by detailed spectroscopic analysis. Compound 5 is the first N‐containing diterpenoid from the genus Isodon, exhibiting notable cytotoxicity against human tumor K562 cells.     

Utility of N‐[4‐(N‐Substituted Sulfamoyl)Phenyl] Cyanothioformamides in the Synthesis of Heterocyclic Compounds

The novel cyanothioformamides 2a‐d were prepared by treatment of isothiocyanatosulfonamides 1a‐d with potassium cyanide at room temperature. Cyclocondensation of compounds 2b,c with phenyl isocyanate as electrophile furnished the corresponding imidazolidines 3a,b . The reactivity of compound 3a towards some nitrogen nucleophiles was investigated. Thus, the thiosemicarbazone 4 and imidazo[4,5‐b]quinoxaline 6 were synthesized by condensation of compound 3a with thiosemicarbazide and o‐phenylenediamine, respectively. Treatment of 3a with hydrochloric acid afforded compound 7 . Our investigation was extended to include the reactivity of cyanothioformamide 2 towards o‐aminophenol, anthranilic acid, and o‐phenylenediamine and yielded the corresponding heterocycles 9 , 11 and 13 derivatives, respectively. Structures of the synthesized compounds were established by their elemental analysis and spectral data.