Two polymorphs of 2,6-dichloropurine, C(5)H(2)Cl(2)N(4), have been crystallized and identified as the 9H- and 7H-tautomers. Despite differences in the space group and number of symmetry-independent molecules, they exhibit similar hydrogen-bonding motifs. Both crystal structures are stabilized by intermolecular N-H···N interactions that link adjacent molecules into linear chains, and by some non...

Efficiency of 6-ethynylpyridone (E), a potential thymine (T) analogue, which forms high-fidelity base pairs with adenine (A) and gives rise to stabler DNA duplexes, with stability comparable to those containing canonical cytosine(C):guanine(G) base pairs, has been reported recently. Estimates of the interaction energies, involving geometry optimization at the DFT level (including middle range d...

Two new Co(II) complexes, [{Co(L)}2{Co(Pic)2(CH3OH)2}] (1) and [{CoL(μ-OAc)}2Co] (2), where H2L = 2,2′-[Ethylenedioxybis(nitrilomethylidyne)]dinaphthol, were designed, synthesized and characterized by elemental analysis, FT-IR spectra, UV-Vis spectra, and X-ray crystallography. Complex 1 consists of two [CoL] and one [Co(Pic)2(CH3OH)2] (Pic = picrate) units and in the [CoL] unit, the Co(II) ato...

Two types of rod-coil block copolymers including poly(3-hexylthiophene)-block-poly(ethylene glycol) (P3HT-b-PEG) and PEG-block-polyaniline (PANI) were synthesized using Grignard metathesis polymerization, Suzuki coupling, and interfacial polymerization. Afterward, two types of single crystals were grown by self-seeding methodology to investigate the coily and rod blocks in grafted brushes and o...

Two series of imidazolium-based ionic liquids (ILs) were tested as rheological modifiers heavy crude oils. ILs with the 1-butyl-3-alkylimidazolium cation optimize effect on viscosity at low concentrations, whereas those 1-benzyl-3-alkylimidazolium are similarly effective only higher which is due to a stronger IL–IL interaction respect IL–asphaltene interaction. The most [C6bim][PF6], [phetbim][...

Butterfly-shaped tetrabenzo[a,c,g,i]fluorene (TBF)-based molecules (1 and 2) were designed, synthesized and well characterized using various spectroscopic techniques. The single crystal X-ray structure of 1 shows the presence of intermolecular 3-D π-π stacking interaction and unprecedented "cold crystallization" in polycyclic aromatic molecules. We report for the first time, the "bottom-up" sel...

In the title salt, C6H6Cl2N(+)·C8H5O4 (-), the carb-oxy-lic acid and carboxyl-ate groups of the anion form dihedral angles of 20.79 (19) and 74.76 (14)°, respectively, with the plane of the benzene ring. In the crystal, mol-ecules are assembled into a two-dimensional polymeric network parallel to (100) via N-H⋯O and O-H⋯O hydrogen bonds. In addition, within the layer, there are π-π stacking int...

The title compound, C(15)H(13)N(3)O(4), was synthesized from dimethyl 1H-pyrazole-3,5-dicarboxyl-ate and 4-(bromo-meth-yl)benzonitrile. The inter-planar angle between the pyrazole and cyano-benzyl ring planes is 71.74 (17)° and an intramolecular C-H⋯O interaction occurs. The crystal structure is stabilized by π-π stacking inter-actions between the neighbouring pyrazole and benzene rings [centro...

A novel sandwich nanomedicine (GO-BNN6) for near-infrared (NIR) light responsive release of nitric oxide (NO) has been constructed by self-assembly of graphene oxide (GO) nanosheets and a NO donor BNN6 through the π-π stacking interaction. The GO-BNN6 nanomedicine has an extraordinarily high drug loading capacity (1.2 mg BNN6 per mg GO), good thermal stability, and high NIR responsiveness. The ...