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The reactions of 2-(4-pyridyl) thiazole-4-carboxylic acid (Hptca) and CuCl2·6H2O have led to a novel 3D mixed-valence, four-copper-center, metal-organic framework (MOF) [Cu8Cl2(ptca)10·17H2O] n (1). The topology analysis using ToposPro software package for 1 resulted in three chain-based topology types of sra (42, 63, 8), pcu (412, 63), and dia (66) via choosing corresponding connection atoms as central atoms. The study indicates that connection atoms associated directly with multiple coordination centers are applicable to act as central atoms. This unique topology analysis approach is conceptually different from the current analytical methods which use node atoms as central atoms. In addition, complex 1 exhibits significant selective adsorption of CO2 over N2. This study provides a great example of the topological analysis of MOFs with multiple coordination centers.

C24H28CuN10O9S, monoclinic, P21/c (no. 14), a = 16.3499(16) Å, b = 14.0411(13) Å, c = 12.7069(13) Å, β = 104.019(2)°, V = 2830.2(5) Å3, Z = 4, R gt(F) = 0.0472, wR ref(F 2) = 0.1165, T = 293(2) K.

Four unexpected 2D lanthanide coordination polymers have been synthesized through in situ reactions of DMF solvent under solvothermal conditions. The isostructural complexes 1–3 contain four types of 2{sub 1} helical chains. While the Nd(III) ions are bridged through μ{sub 2}-HIDC{sup 2−} and oxalate to form a 2D sheet along the bc plane without helical character in 4. Therefore, complex 1 exhibits bright red solid-state phosphorescence upon exposure to UV radiation at room temperature. - Graphical abstract: Four unexpected 2D lanthanide coordination polymers have been synthesized through in situ reactions of solvent DMF to formate acid or oxalic acid under solvothermal conditions. The isostructural complexes 1–3 contain four types of different 2{sub 1} helical chains in the 2D layer and 1 exhibits bright red solid-state phosphorescence upon UV radiation. - Highlights: • Four unexpected 2D lanthanide coordination compounds have been synthesized through in situ reactions under solvothermal conditions. • The complexes 1–3 contain four types of 2{sub 1} helical chains in the layer. • Complex 1 exhibits bright red solid-state phosphorescence upon exposure to UV radiation at room temperature.

Two new zinc(II) metal–organic compounds of [Zn(ADC)(bimh)]n (1) and [Zn(ADA)(bimh)]n (2) (H2ADC = 1,3-adamantanedicarboxylic acid, H2ADA = 1,3-adamantanediacetic acid, bimh = 1,6-bis(2-methyl-imidazole-1-yl)-hexane, have been structurally characterized by X-ray diffraction analysis. In compound 1, the zinc(II) ions are bridged by ADC and bimh ligands to form a 1D looped chain. In compound 2, the ADA molecules alternately bridge Zn(II) atoms to form infinite chains, and then the 1D chain is connected through the bimh ligand resulting in an undulating infinite two-dimensional (2D) polymeric network. Additionally, TG analysis, XRPD and fluorescent properties for compounds 1 and 2 are also measured and discussed.

A rarely reported L1D (left-handed helical 1D chain) + R1D (right-handed helical 1D chain) → 3D polycatenated network, [Cd(H2ttac)bpp]n (1), constructed from the vertical interpenetration of triple-stranded homochiral helices, has been synthesized under hydrothermal condition by H4ttac (1,1′,2′,1″-terphenyl-4,4′,4″,5′-tetracarboxylic acid), 1,3-bis(4-pyridyl)propane (bpp), and Cd(NO3)2·4H2O. The luminescent properties of 1 and the ones immersed in various kinds of organic compounds and nitrate@DMF solutions have been investigated. Importantly, 1 shows highly sensitive response to nitro aromatic compounds and Cu2+ through luminescence quenching effects, making it a promising luminescent sensor for nitro aromatic compounds and Cu2+. Besides, experiments upon deprotonation by NaOH, KOH, methylamine, and triethylamine are conducted, respectively. As base increases, the luminescence spectra exhibit gradual blue shifts. The mechanisms of the sensing properties have been studied in detail.

C18H24N6Na2O10, triclinic, P1̄, a = 6.223(2) Å, b = 7.385(2) Å, c = 14.295(4) Å, α = 75.491(6)°, β = 77.953(6)°, γ = 70.523(6)°, V = 593.9(3) Å3, Z = 1, R gt(F) = 0.0517, wR ref(F 2) = 0.1533, T = 296(2) K.

We show here the supramolecular isomerism, with respect to shape-asymmetry of ligand and the new hierarchical classification for supramolecular isomerism, the three-level isomerism, which was advanced based on a thorough investigation for the four new Ni/dpt24 polymorphs [Hdpt24 = 3-(2-pyridyl)-5-(4-pyridyl)-1,2,4-triazole)]. Compounds 1, 2, and 3 are three-dimensional twofold interpenetrated porous coordination polymers with NbO topology, while 4 with two-dimensional grid structure is termed as the primary isomer of 1/2/3 due to the difference of dimensionality. Complex 3 possessing different shape-asymmetry of single networks from 1 and 2, is called as the secondary isomer of 1 and 2. Complexes 1 and 2 possess the same topology, single shape-asymmetry networks, but different interpenetration-orientation and interpenetration-asymmetry, and are defined as the tertiary isomers. Distinct differences in H2 and CO2 adsorption capacity were observed among each level of isomers. In addition, the hierarchical classification's relationship with characteristic classifications has been discussed.

Under solvothermal conditions, reactions of pyridine-3,5-bis(phenyl-4-carboxylic acid) (H2L) with lanthanide metal salts give rise to three new metal-organic frameworks (MOFs) with the formula {[Ln4(L)3(μ3-OH)4(H2O)4]·(NO3)2·solvent}n [Ln = Er (1), Yb (2) and Lu (3)]. The complexes were characterized by single crystal and powder X-ray diffraction, IR and thermogravimetric analyses. They have the same two-fold interpenetrating three-dimensional (3D) framework structures with [Ln4(COO)6(μ3-OH)4(H2O)4] clusters as secondary building units (SBUs) and a rare 6-connected lcy topology with the point (Schläfli) symbol of {3(3)·5(9)·6(3)}. Interestingly, 1-3 show selective and hysteretic sorption of CO2 over N2, and the photoluminescence properties of the complexes were also investigated.

C9H13AgN4O4, monoclinic, C2/c (no. 15), a = 28.123(3) Å, b = 7.0409(7) Å, c = 14.1954(15) Å, β = 119.488(2)°, V = 2446.8(4) Å3, Z = 8, R gt(F) = 0.0206, wR ref(F 2) = 0.0558, T = 296(2) K.

C18H13AgN6O4, monoclinic, C2/c (no. 15), a = 12.9022(12) Å, b = 8.9088(8) Å, c = 15.3383(14) Å, β = 106.810(3)°, V = 1687.7(3) Å3, Z = 4, R gt(F) = 0.0247, wR ref(F 2) = 0.0600, T = 296(2) K.

In this study, two new isomorphic binuclear compounds, [Ln(µ-NAP)4(NAP)2(phen)2] · H2O (1) and (2) (Ln = Eu, Tb, NAP = N-acetyl-N-phenylglycinate; phen = 1,10-phenanthroline), have been synthesized and characterized by infrared spectroscopy, elemental analysis, and X-ray crystallography. These compounds crystallize in a triclinic form with space group Pī with a = 11.7519(11), b = 13.4293(12), c = 14.0686(13) A, V = 1992.7(3) A3, and Z = 1. Single-crystal X-ray structural analysis reveals that 1 is binuclear, assembled into a 3-D supramolecular network with self-complementary double hydrogen-bonding interactions and aromatic π–π interactions. Fluorescence properties of 1 and 2 are also discussed.

Three new silver(I) metal−organic frameworks (MOFs), namely, [Ag2(pda)(bipy)2]n·4nH2O (1), [Ag2(pda)(dpe)2(H2O)]n·4nH2O (2), and [Ag(Hpda)(bpp)]n (3), were prepared by hydrothermal reactions of silver(I) acetate with H2pda (H2pda = 1,2-phenylenediacetic acid) in the presence of different pyridyl-containing ligands (bipy = 4,4′-bipyridine, dpe = 1,2-di(4-pyridyl)-ethylene, and bpp = 1,2-bis(4-pyridyl)propane) and structurally characterized by single crystal X-ray diffraction. Complex 1 shows a two-dimensional (2D) four-connected network with a long topological vertex Schlafli symbol (4.62.4.63.64.6). Of particular interest, a new unreported octameric water cluster, (H2O)8, which is comprised of a cyclic water tetramer and four dangling water monomers, exists in 1. And the pseudorotaxane motifs are formed by these octameric clusters and the [Ag8(pda)2(bipy)4] loops. Complex 2 features a one-dimensional (1D) ladder-like chain structure, and the 2D networks, assembling by the combination of the pentameric wat...

Two novel 1D compounds {[Ag 3 (Hbptc)(bpa) 2 ]·H 2 O} n ( 1 ) and [Ag 2 (H 2 bptc)(bpp) 2 ] n ( 2 ) (H 4 bptc = 3,3′,4,4′-benzophenonetetracarboxylic acid, bpa = 1,2-bis(4-pyridyl)ethane and bpp = 1,3-bis(4-pyridyl)propane) were synthesized and structurally characterized. The crystal structures of compounds exhibit two kinds of ladder-like chains based on linear or T-shaped coordination environment of Ag(I). Fluorescence spectra of compounds 1 and 2 indicate the unusual intensity of fluorescent emission upon photoexcitation which may be attributed to ligand-to-metal charge transfer and Ag–Ag interactions.

An unusual 1D ladder-like silver(I) complex has been synthesized and characterized. The polymer exhibits interesting plywood-like stacking arrays and a novel five-folded interpenetrated supramolecular network with [3 + 2] catenations.

The intein expression system has been widely applied in Escherichia coli to express various proteins and peptides. However, the removal of endotoxin from the recombinant proteins expressed in E. coli is very difficult and therefore complicates the purification process. In this study, we constructed an intein-based expression vector for an antimicrobial peptide (cathelicidin from Bungarus fasciatus) and expressed the intein fusion peptide in a Bacillus subtilis expression system. The fusion peptide was secreted into the culture medium, identified by Western blot and purified by affinity chromatography and intein self-cleavage in just one step. Approximately, 0.5 mg peptide was obtained from 1 litre of culture medium. The purified peptide showed antimicrobial activity. Our results indicate that the intein expression system may be a safe and efficient method to produce soluble peptides and proteins in B. subtilis.

The title compound, {[Ni(C2H8N2)3][Cd(C4N2S2)2]·H2O}n, contains chains of bis­(1,2-dicyano­ethyl­enedithiol­ato)­cadmate(II) complex anions, tri(ethyl­enediamine)nickel(II) cations and uncoordinated water mol­ecules. The CdII centre is in a very distorted CdS6 octa­hedral environment. Three bidentate ethyl­enediamine ligands are coordinated to the NiII atom, resulting in somewhat distorted NiN6 octa­hedra. The polymeric anionic chains, cations and water mol­ecules are linked by hydrogen bonds into a three-dimensional framework.

In the title compound, C12H9N2+·C7H5O4N−·C12H8N2·C7H4O4N·C2H6O·H2O, the cations are stacked along the b axis to form a column-like structure. The anions, ethanol mol­ecules and water mol­ecules are linked via O—H⋯O and O—H⋯N hydrogen bonds to form a zigzag sheet-like structure. The cationic columns and anionic sheets are alternately arranged along the c axis.

In the title compound, (C2H10N2)[Zn(C2H8N2)2(H2O)2][Zn(C7H3NO4)2]2·2H2O, the Zn atom (site symmetry 2/m) in the [Zn(C2H8N2)2(H2O)2]2+ cation is six-coordinated by four N atoms from bidentate ethyl­enediammonium molecules and two water O atoms. The Zn atom (site symmetry 2) in the [Zn(C7H3NO4)2]2− anion is six-coordinated by four O atoms and two N atoms from two tridentate pyridine-2,6-dicarboxyl­ate ligands. An uncoordinated ethyl­enediammonium cation and two water mol­ecules are also present in the structure. The crystal packing is stabilized by O—H⋯O and N—H⋯O hydrogen bonds, forming a three-dimensional network.

In the title complex, [Ce2(C10H10NO3)6(C12H8N2)2]·2H2O, each Ce atom shows a distorted tricapped trigonal prismatic coordination, comprising two N-atom donors from a 1,10-phenanthroline ligand and seven O atoms of the N-acetyl-N-phenyl­glycine (L2) mol­ecules. Two Ce atoms are bridged by two terdentate and two bidentate carboxyl­ate groups of L2, to give a centrosymmetric dimer. The crystal structure is stabilized by intermolecular O—H⋯O hydrogen bonds.

In the title complex, [Cd(C2H8N2)3][Cu(C4N2S2)2], the CdII atom has a distorted octahedral geometry. The CuII atom is in a distorted square-planar geometry. Both ions lie on twofold rotation axes. They are not connected covalently.

The title complex, [Cu(S2O3)(C2H8N2)2], exhibits a slightly distorted square-pyramidal geometry. The copper(II) atom is five-coordinated by four N atoms from two ethyl­enedi­amine mol­ecules, and one S-atom from the thio­sulfate anion. The crystal structure is stabilized by weak intermolecular Cu⋯S interactions and N—H⋯O hydrogen bonds.

In the title complex, [La2(C10H10NO3)6(C12H8N2)2]·2H2O, the LaIII atoms are bridged by two terdentate and two bidentate carboxyl­ate groups with an inversion centre between the two LaIII ions. Each La atom is nine-coordinated by two N atoms of 1,10-phenanthroline and seven O atoms belonging to N-acetyl-N-phenyl­glycine mol­ecules, and exhibits distorted tricapped trigonal prismatic geometry. The crystal structure is stabilized by intermolecular O—H⋯O hydrogen bonds.

In the title complex, [La2(C10H10NO3)2(C12H8N2)4(H2O)6](C10H10NO3)2(NO3)2·2H2O, each LaIII ion is nine-coordinated by four N atoms from two bidentate 1,10-phenanthroline ligands and by five O atoms (two from N-acetyl-N-phenyl­glycinate ligands and three from water mol­ecules). The LaIII cations, which exhibit distorted tricapped trigonal prismatic coordination, are bridged by two N-acetyl-N-phenyl­glycinate ligands into a dimeric structure, generated by inversion symmetry. The crystal structure is stabilized by a three-dimensional hydrogen-bond network.

Through middle-temperature solvothermal reactions of CoCl(2).6H(2)O with the rigid-angled ligand 3-(2'-pyridyl)-5-(4''-pyridyl)-1,2,4-triazole (Hdpt24), we obtained the three cobalt complexes {[Co(dpt24)(2))](3).4DMF.1.5H(2)O}(n) (1), {[Co(dpt24)(2))](2).H(2)O}(n) (2), and Co(dpt24)(2)(Hdpt24).H(2)O] (4) at N,N-dimethylformamide (DMF)/H(2)O volume ratios of 9:1, 1:1, and 0:1, respectively. Interestingly, 1 underwent transformations into 2, {[Co(dpt24)(2)].0.5DMF}(n) (3), and 4 when treated with DMF/H(2)O at volume ratios of 1:1, 1:9, and 0:1, respectively. Moreover, 3 and 4 converted back to 1 in 9:1 DMF/H(2)O and to 2 in 1:1 DMF/H(2)O; 3 transformed into 4 in H(2)O and vice versa in 1:9 DMF/H(2)O. Structurally, 1 is a three-dimensional (3D) 2-fold interpenetrating distorted NbO-type complex, 2 possesses a two-dimensional layer metal-organic framework, 3 is a 3D 2-fold interpenetrating typical NbO-type complex, and 4 is a wheel-shaped mononuclear neutral complex. This approach, using a mixed solvent's component ratio to direct the syntheses and conversions of four cobalt complexes, provides unprecedented control for crystal engineering.

The asymmetric unit of the title structure, C27H24Br2P+·Br−, comprises two [(CH3C6H3CHBr2)(C6H5)3P]+ cations and two bromide anions. The cations exhibit closely comparable conformations, with a slight distortion from tetra­hedral geometry around P.

In the title compound, [Cd(H2O)6](C15H15O2)2·2H2O, the hexa­aqua­cadmium(II) cation possesses a crystallographically imposed centre of symmetry. In the crystal structure, the [Cd(H2O)6]2+ cations, 4-[2-(4-hydroxy­phen­yl)-2-prop­yl]phenolate anions and solvent water mol­ecules are connected through a complex pattern of O—H⋯O hydrogen bonds.

The structure of the title amino acid, C10H11NO3, is stabilized by O—H⋯O hydrogen bonds, connecting the mol­ecules into infinite chains along the b axis.

In the title complex, [Co(C6H4O2N)3]·H2O, the cobalt(III) ion shows a distorted octahedral coordination, comprising three N-atom donors and three O-atom donors from three bidentate pyridine-2-carboxyl­ate ligands. The uncoordinated water mol­ecule interacts with nearby carboxyl groups of the pyridine-2-carboxyl­ate ligands by way of O—H⋯O hydrogen bonds.

The title complex, [Zn(C2H8N2)3][Cu(C4N2S2)2], exists as discrete ions. The cation lies on a twofold rotation axis and the anion lies on an inversion centre. The [Zn(C2H8N2)3]2+ cation exhibits a distorted octahedral geometry. In the [Cu(C4N2S2)2]2− anion, the CuII atom is in a slightly distorted square-planar environment. The crystal packing is stabilized by hydrogen bonds of the types N—H⋯N and N—H⋯S.

In the title complex, (C2H10N2)2[Cd(C7H3NO4)3]·6H2O, the CdII atom is nine-coordinated by three pyridine-2,6-di­carboxyl­ate ligands via six O atoms and three N atoms in a distorted tricapped trigonal prismatic structure. A crystallographic twofold rotation axis passes through the Cd atom and three atoms of one pyridine ring, viz. N, the C in the p-position and its attached H atom. The pyridine-2,6-di­carboxyl­ate ligands, ethyl­enedi­ammonium cations and uncoordinated water mol­ecules contribute to the formation of intermolecular hydrogen bonds, forming a three-dimensional network.

In the title compound, [Zn(C10H10NO3)2(C12H8N2)(H2O)], the ZnII atom is five-coordinated by the two N atoms of the 1,10-phenanthroline ligand, two O atoms from two benzoyl­alanine ligands and one O from a water mol­ecule. The complex exhibits a slightly distorted square-pyramidal geometry. The crystal structure is stabilized by hydrogen bonds of the types N—H⋯O, O—H⋯O and C—H⋯O.

A series of new metal–organic frameworks (MOFs), [Zn(1,2-pda)(bipy)(H2O)2]n (1), [Zn(1,3-pda) (bipy)(H2O)]n·nH2O (2), [Zn(1,4-pda)(bipy)]n·nCH3OH (3), [Zn(1,2-pda)(dpe)]n·3nH2O (4), and [Zn(1,3-pda)(bpa)]n·2nH2O (5) [H2pda = phenylenediacetic acid, bipy = 4,4′-bipyridine, dpe = 1,2-di(4-pyridyl)ethylene, bpa = 1,2-bis(4-pyridyl)ethane] have been synthesized and structurally characterized. The structure determination reveals that complex 1 is a 2D layered network and exhibits a typical (4,4) topological net, which further assembles into a 3D two-fold interpenetrated pcu topology when hydrogen bonding interactions are considered. Complex 2 shows a 2D (5,2)-connected topological network via hydrogen bonding interactions based on the 1D double-chains. For complex 3, when the 1,4-pda ligands act as a three-connected node, the 2D double-layered structure displays a unique (5,3)-connected topology with a Schlafli symbol (42,67,8)(42,6). Complex 4 features a rare 3D three-fold interpenetrated diamondoid framework (dia, 66 topology) with (2.2.1) Hopf links and (6.3.3) Torus links, and the helical water chains are encased in the 1D neighboring channels. Complex 5 is a 2D corrugated net with a Schlafli symbol (44,62), and the puckered nature of the layers assembles them to interpenetrate in an unusual 2D → 3D parallel fashion. Particularly, a discrete tetramer water cluster, (H2O)4, is located in the crystal lattice of 5. The structural differences demonstrate that the backbones of the phenylenediacetic acids are a key point to form the final metal–ligand coordination polymers. Moreover, the fluorescent properties of complexes 1–5 were studied in the solid state at room temperature.

Self-assembly led to a fascinating type of 2D → 3D polythreaded architecture with different side arms involving nine polymeric units at a time, which exhibits the highest threaded degree presently known for 2D motifs. Especially, when hydrogen bonds are taken into account, the resulting structure displays topologically a 5-fold interpenetrated 3D mot framework.