Crystal structure of MgK0.5[B6O10](OH)0.5·0.5H2O, poly[dimagnesium potassium bis(hexa-borate) hy-droxide monohydrate].

The solvothermal reaction of H3BO3, KCF3SO3, Mg(CF3SO3)2 and pyridine led to a new alkali- and alkaline-earth-metal borate, MgK0.5[B6O10](OH)0.5·0.5H2O. Its structure features an intricate three-dimensional framework built from [B6O13]8- clusters, thus resulting in a six-connected achiral net with high symmetry. Each [B6O13]8- building block is composed of three trigonal BO3 and three tetra-hedral BO4 units, with these BO4 units being further connected to neighboring BO3 units, giving rise to an oxoboron cluster of the general formula [B6O10]2-.

Crystal structure of Rb6[B12O18(OH)6]·2H2O.

The solvothermal reaction of H3BO3, sodium tert-butoxide, Rb2CO3 and pyridine led to a new alkaline metal borate hexa-rubidium hexa-hydroxy-dodeca-borate dihydrate, Rb6[B12O18(OH)6]·2H2O. Its structure contains a large cyclic dodeca-oxoboron cluster, [B12O18(OH)6]6-, formed by six {B3O3} rings. In the crystal, O-H⋯O hydrogen bonds between the components lead to the formation of a three-dimensional supra-molecular framework.

Crystal structure of 4,4'-(diazenediyl)dipyridinium nitrate perchlorate.

The title compound, C10H10N4 2+·NO3 -·ClO4 -, was obtained unexpectedly by the reaction of Co(ClO4)2·6H2O and cytidine-5'-monophosphate with 4,4'-azo-pyridine in an aqueous solution of nitric acid. The mol-ecular structure comprises two planar 4,4'-diazenediyldipyridinium dications lying on inversion centres and perchlorate and nitrate anions in general positions. In the crystal, N-H⋯O hydrogen bonds between dications and anions lead to the formation of [232] chains.

K2 Na3 [{B6 O10 (OH)}{B3 O4 (OH)3 }] ⋠H2 O: A Layered Borate Built by Mixed Oxoboron Clusters with Nonlinear-Optical Property.

A new acentric borate, K2 Na3 [{B6 O10 (OH)}-{B3 O4 (OH)3 }] ⋅ H2 O (1) has been made under solvothermal condition. 1 has layered structure made by B6 O13 (OH)-based chains and B3 O5 (OH)3 -bridging clusters. Second-harmonic generation (SHG) measurements reveal that 1 is a phase-matchable nonlinear optical (NLO) material, showing the SHG signal intensity of 1.8 times that of KDP (KH2 PO4 ). Besides, UV-Vis diffuse reflectance spectrum shows that 1 has the short deep UV (DUV) absorption cutoff edge of 198 nm. Thermogravimetric analysis reveals it has good thermal stability. Also 1 represents firstly mixed oxoboron clusters-made 2D layered borate with NLO property.

The Research of G-Motif Construction and Chirality in Deoxyguanosine Monophosphate Nucleotide Complexes.

A detailed understanding of the mismatched base-pairing interactions in DNA will help reveal genetic diseases and provide a theoretical basis for the development of targeted drugs. Here, we utilized mononucleotide fragment to simulate mismatch DNA interactions in a local hydrophobic microenvironment. The bipyridyl-type bridging ligands were employed as a mild stabilizer to stabilize the GG mismatch containing complexes, allowing mismatch to be visualized based on X-ray crystallography. Five single crystals of 2'-deoxyguanosine-5'-monophosphate (dGMP) metal complexes were designed and obtained via the process of self-assembly. Crystallographic studies clearly reveal the details of the supramolecular interaction between mononucleotides and guest intercalators. A novel guanine-guanine base mismatch pattern with unusual (high anti)-(high anti) type of arrangement around the glycosidic angle conformations was successfully constructed. The solution state 1H-NMR, ESI-MS spectrum studies, and UV titration experiments emphasize the robustness of this g-motif in solution. Additionally, we combined the methods of single-crystal and solution-, solid-state CD spectrum together to discuss the chirality of the complexes. The complexes containing the g-motif structure, which reduces the energy of the system, following the solid-state CD signals, generally move in the long-wave direction. These results provided a new mismatched base pairing, that is g-motif. The interaction mode and full characterizations of g-motif will contribute to the study of the mismatched DNA interaction.

Two new Cu-based borate catalysts with cubic supramolecular cages for efficient catalytic hydrogen evolution.

Focusing on renewable energy, we are devoted to developping efficient, robust and low cost water reduction catalysts (WRCs). Two new Cu-based borate catalysts, namely H2Na2K2[(µ4-O)Cu4@B20O32(OH)8]·21H2O (1) and H2Rb1.6K2.4[(µ4-O)Cu4@B20O32 (OH)8]·15H2O (2), with cubic supramolecular cages were synthesized under a hydrothermal condition. Moreover, new copper complexes were applied as water reduction catalysts (WRCs) in the presence of [Ir(ppy)2(dtbbpy)][PF6] as photosensitizer and triethanolamine (TEOA) as the sacrificial electron donor. Nevertheless, the main active place is attributed to the centre of Borates [(µ4-O)Cu4@B20O32(OH)8], and the atomic radius of the counter cation would be the critical factor of the photocatalytic activity. Increasing the atomic radius from the Na atom to the Rb atom, causes the photocatalytic activity to decrease efficiently. The experimental results match well with the density functional theory (DFT) conclusion. It is noteworthy to mention that our research not only enriches the Cu-based borate chemistry, but also investigates the photocatalytic activity of Cu-based borates. This would guide us through the borate synthesis and to develop their applications toward energy and the environment.

Double layer zinc-UDP coordination polymers: structure and properties.

A homochiral Zn-UDP coordination polymer with an alternating parallel ABAB sequence was constructed and studied by X-ray single crystal diffraction analysis. Its crystal structure shows that there are potentially open sites in the 2D layers. The activation of the sites makes the coordination polymer a fluorescent sensor for novel heterogeneous detection of amino acids.

Cytosine-Cytosine Base-Pair Mismatch and Chirality in Nucleotide Supramolecular Coordination Complexes.

The base-pair sequences are the foundation for the biological processes of DNA or RNA, and base-pair mismatch is very important to reveal genetic diseases and DNA rearrangements. However, the lack of well-defined structural information about base-pair mismatch is obstructing the investigation of this issue. The challenge is to crystallize the materials containing the base-pair mismatch. Engineering the small-molecule mimics or model is an effective strategy to solve this issue. Here, six cytidine-5'-monophosphate (CMP) and 2'-deoxycytidine-5'-monophosphate (dCMP) coordination polymers were reported containing cytosine-cytosine base-pair mismatch (i-motif), and their single-crystal structures and chiralities were studied. The precise control over the formation of the i-motif was demonstrated, in which the regulating of supramolecular interactions was achieved based on molecular design. In addition, the chiralities of these coordination polymers were investigated according to their crystal structures and solution- and solid-state circular dichroism spectroscopy.

Controllable synthesis of nucleotide complex based on pH control: a small-molecule fluorescent probe as an auxiliary ligand to indicate the pre-organization of the nucleotide complex in solution.

Different CMP-bpe-M(ii) (CMP = cytidine monophosphate, bpe = bis(4-pyridyl)ethylene, M(ii) = Mn(2+) and Co(2+)) complexes are synthesized controllably based on pH control and well studied by X-ray single-crystal diffraction analysis. Interestingly, the suitable pH conditions are explored by considering the pre-organization modes of CMP, bpe, and M(2+) in aqueous solution by fluorescence spectroscopy based on acid/basic titration. The organic base bpe serves as a small-molecule fluorescent probe to indicate the changes of pre-organization modes along with the changes of the solution acidity. Furthermore, a perfect self-complementary sugar-base hydrogen bond is first reported based on the crystal structure analysis in this work, and different chiralities and SHG activities of CMP-bpe-Mn(ii) complexes obtained at different pH values are studied.

6-Nitro-1,3-benzothia-zole-2(3H)-thione.

In the title mol-ecule, C(7)H(4)N(2)O(2)S(2), the nitro group is twisted by 5.5 (1)° from the plane of the attached benzene ring. In the crystal, N-H⋯S hydrogen bonds link pairs of mol-ecules into inversion dimers, which are linked by weak C-H⋯O inter-actions into sheets parallel to (101). The crystal packing exhibits short inter-molecular S⋯O contacts of 3.054 (4) Šand π-π inter-actions of 3.588 (5) Šbetween the centroids of the five- and six-membered rings of neighbouring mol-ecules.

Iodido[5-methyl-1H-benzimidazole-2(3H)-thione-κS]bis-(triphenyl-phosphane-κP)copper(I) methanol monosolvate.

In the title compound, [CuI(C(8)H(8)N(2)S)(C(18)H(15)P)(2)]·CH(3)OH, the coordination environment around the Cu(I) atom is distorted tetra-hedral, defined by two P atoms of two triphenyl-phosphane ligands, one S atom of a 5-methyl-1H-benzimidazole-2(3H)-thione ligand and one I atom. The complex mol-ecules and the methanol solvent mol-ecules are connected via N-H⋯O and O-H⋯I hydrogen bonds, forming a chain along [010]. An intra-molecular N-H⋯I hydrogen bond is also observed.

3-Amino-1H-1,2,4-triazole-5(4H)-thione-4,4'-bipyridine (1/1).

The title two-component mol-ecular crystal, C(10)H(8)N(2)·C(2)H(4)N(4)S, was obtained unexpectedly by reaction of Zn(NO(3))(2)·6H(2)O, NH(4)BF(4) with 3-amino-1,2,4-triazole-5-thione (3-AMT) and 4,4'-bipyridine in water. The dihedral angle between the pyridine rings in the 4,4'-bipyridine molecule is 17.00 (13)°. In the crystal, N-H⋯N and N-H⋯S hydrogen bonds between the components lead to the formation of a three-dimensional network. Furthermore, the structure features face-to-face π-π stacking inter-actions between the 4,4'-bipyridine and triazole rings, with a centroid-centroid distance of 2.976 (2) Å.

catena-Poly[[[diaqua-(1,10-phenanthroline-κ(2)N,N')zinc]-µ-4,4'-bipyridine-κ(2)N:N'] dinitrate 4,4'-bipyridine hemisolvate monohydrate].

In the title compound, [Zn(C(10)H(8)N(2))(C(12)H(8)N(2))(H(2)O)(2)](NO(3))(2)·0.5C(10)H(8)N(2)·H(2)O, the Zn(II) atom is coordinated in a distorted octa-hedral geometry by two N atoms from two 4,4'-bipyridine (4,4'-bipy) ligands, two N atoms from a chelating 1,10-phenanthroline ligand and two O atoms from two mutually cis water mol-ecules. The 4,4'-bipy ligands bridge the Zn(II) atoms into a chain structure along [100]. The uncoordinated 4,4'-bipy mol-ecule lies on an inversion center. O-H⋯O and O-H⋯N hydrogen bonds connect the cationic chains, the nitrate anions, the uncoordinated 4,4'-bipy mol-ecules and the water mol-ecules into tow-dimensional networks.

Bis[µ-bis-(diphenyl-phosphan-yl)methane-κ(2)P:P']bis-[(isoquinoline-κN)silver(I)] bis-(trifluoro-methane-sulfonate)-isoquinoline (1/1).

The title complex, [Ag(2)(C(25)H(22)P(2))(2)(C(9)H(7)N)(2)](CF(3)SO(3))(2)·C(9)H(7)N, was prepared by the reaction of silver(I) trifluoro-methane-sulfonate with isoquinoline and bis-(diphenyl-phosphan-yl)methane (dppm). The dinuclear mol-ecule is located about a center of inversion and the Ag(I) atom is coordinated by two dppm P atoms and one isoquinoline N atom, forming an eight-membered metalla ring. In addition, in the asymmetric unit, there is a half-mol-ecule of isoquinoline located about a center of inversion. Since this mol-ecule does not possess this symmetry, for one position in the ring there is superposition of both a C atom of a C-H group and the isoquinoline N atom. In the structure, the Ag-P distances [2.4296 (9) and 2.4368 (9) Å] agree with the corresponding distances in related structures, while the Ag-N bond length [2.489 (3) Å] is slightly longer than that in related structures. On the other hand, the P-Ag-P angle [156.44 (3)°] is much larger than the corresponding angles in related structures. The trifluoro-methane-sulfonate anions do not coordinate to Ag(I) atoms. As is usually found for these anions, the -CF(3) group is disordered over two orientations [occupancies = 0.57 (12) and 0.43 (12)].

Tetra-kis(triphenyl-phosphane-κP)silver(I) tetra-fluorido-borate.

The title complex, [Ag(C(18)H(15)P)(4)]BF(4), was prepared by the reaction of silver(I) tetra-fluorido-borate and triphenyl-phosphane in the presence of 1,2-bis-(pyridin-2-yl)ethyl-ene. The Ag(I) atom is tetra-hedrally coordinated by four P atoms from triphenyl-phosphane (PPh(3)) ligands. Due to symmetry, the tetra-fluorido-borate anion is disordered over three positions (each with one third occupancy). The tetra-fluorido-borate anion does not coordinate to the Ag(I) atom.

5,6-Dimethyl-1,2,4-triazin-3-amine.

In the crystal structure of the title compound, C(5)H(8)N(4), adjacent mol-ecules are connected through N-H⋯N hydrogen bonds, resulting in a zigzag chain along [100]. The amino groups and heterocyclic N atoms are involved in further N-H⋯N hydrogen bonds, forming R(2) (2)(8) motifs.

4,4'-Bipyridine-1,1'-diium bis-(1,3-benzo-thia-zole-2-thiol-ate).

In the title salt, C10H10N2(2+)·2C7H4NS2(-), the complete 4,4'-bipyridine-1,1'-diium dication is generated by a center of symmetry. In the crystal, N-H⋯N hydrogen bonds are observed between the cations and anions.

[Bis[µ-bis-(diphenyl-phosphino)methane-1:2κ(2)P:P']-bis-(nitrito-κ(2)O,O')]disilver(I) acetonitrile disolvate.

The title complex, [Ag(2)(NO(2))(2)(C(25)H(22)P(2))(2)]·2CH(3)CN, is a centrosymmetric dimer in which two bis(diphenylphosphino)methane ligands bridge two Ag(+) ions, forming an eight-membered ring with a short Ag⋯Ag separation of 3.1809 (5) Å. The distorted P(2)O(2) coordination of the cation is completed by two O-donors from a symmetric bidentate chelate NO(2) (-) anion [Ag-O = 2.550 (3) and 2.567 (3) Å].

4,4'-Bipyridine-3,3'-disulfanediyl-bis-(1H-1,2,4-triazole-5-amine) (1/1).

In the title 1:1 adduct, C(10)H(8)N(2)·C(4)H(6)N(8)S(2)·, the components are connected through N-H⋯N hydrogen bonds, leading to a two-dimensional structure. The C-S-S-C torsion angle is -83.6 (1)°. The dihedral angle between pyridine rings is 1.86 (15)°.

An ortho-rhom-bic polymorph of pyrazino-[2,3-f][1,10]phenanthroline-2,3-dicarbonitrile.

The title compound, C(16)H(6)N(6), is a polymorph of the previously reported structure [Kozlov & Goldberg (2008 ▶). Acta Cryst. C64, o498-o501]. Unlike the previously reported monoclinic polymorph (space group P2(1)/c, Z = 8), the title compound reveals ortho-rhom-bic symmetry (space group Pnma, Z = 4). The mol-ecule shows crystallographic mirror symmetry, while the previously reported structure exhibits two independent mol-ecules per asymmetric unit. In the title compound, adjacent mol-ecules are essentially parallel along the c axis and tend to be vertical along the b axis with dihedral angles of 72.02 (6)°. However, in the reported polymorph, the entire crystal structure shows an anti-parallel arrangement of adjacent columns related by inversion centers and the two independent mol-ecules are nearly parallel with a dihedral angle of 2.48 (6)°.